deployment: update VictoriaMetrics release tag from v1.91.3 to v1.92.0

This should prevent from connection leaks

See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4724

.github/ISSUE_TEMPLATE/question.yml

@@ -0,0 +1,32 @@
+name: Question
+description: Ask a question regarding VictoriaMetrics or its components
+labels: [question]
+body:
+  - type: textarea
+    id: describe-the-component
+    attributes:
+      label: Is your question request related to a specific component?
+      placeholder: |
+        VictoriaMetrics, vmagent, vmalert, vmui, etc...
+    validations:
+      required: false
+  - type: textarea
+    id: describe-the-question
+    attributes:
+      label: Describe the question in detail
+      description: |
+        A clear and concise description of the issue and the question.
+    validations:
+      required: true
+  - type: checkboxes
+    id: troubleshooting
+    attributes:
+      label: Troubleshooting docs
+      description: I am familiar with the following troubleshooting docs
+      options:
+        - label: General - https://docs.victoriametrics.com/Troubleshooting.html
+          required: false
+        - label: vmagent - https://docs.victoriametrics.com/vmagent.html#troubleshooting
+          required: false
+        - label: vmalert - https://docs.victoriametrics.com/vmalert.html#troubleshooting
+          required: false

.github/dependabot.yml

@@ -8,10 +8,12 @@ updates:
     directory: "/"
     schedule:
       interval: "weekly"
+    open-pull-requests-limit: 0
   - package-ecosystem: "bundler"
     directory: "/docs"
     schedule:
-      interval: "daily"
+      interval: "weekly"
+    open-pull-requests-limit: 0
   - package-ecosystem: "gomod"
     directory: "/app/vmui/packages/vmui/web"
     schedule:

.github/workflows/check-licenses.yml

@@ -17,7 +17,7 @@ jobs:
       - name: Setup Go
         uses: actions/setup-go@main
         with:
-          go-version: 1.20.0
+          go-version: 1.20.6
         id: go
       - name: Code checkout
         uses: actions/checkout@master

.github/workflows/codeql-analysis.yml

@@ -55,9 +55,9 @@ jobs:
         uses: actions/checkout@v3
 
       - name: Set up Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v4
         with:
-          go-version: 1.20.0
+          go-version: 1.20.6
           check-latest: true
           cache: true
         if: ${{ matrix.language == 'go' }}

.github/workflows/main.yml

@@ -30,9 +30,9 @@ jobs:
         uses: actions/checkout@v3
 
       - name: Setup Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v4
         with:
-          go-version: 1.20.0
+          go-version: 1.20.6
           check-latest: true
           cache: true
 
@@ -54,9 +54,9 @@ jobs:
         uses: actions/checkout@v3
 
       - name: Setup Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v4
         with:
-          go-version: 1.20.0
+          go-version: 1.20.6
           check-latest: true
           cache: true
 
@@ -79,9 +79,9 @@ jobs:
 
       - name: Setup Go
         id: go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v4
         with:
-          go-version: 1.20.0
+          go-version: 1.20.6
           check-latest: true
           cache: true
 

.github/workflows/nightly-build.yml

@@ -1,48 +0,0 @@
-name: nightly-build
-on:
-  schedule:
-    # Daily at 2:48am
-    - cron: '48 2 * * *'
-
-permissions:
-  contents: read
-
-jobs:
-  build:
-    name: Build
-    runs-on: ubuntu-latest
-    steps:
-      - name: Login to Docker Hub
-        uses: docker/login-action@v2
-        with:
-          username: ${{ secrets.DOCKERHUB_USERNAME }}
-          password: ${{ secrets.DOCKERHUB_TOKEN }}
-      - name: Setup Go
-        uses: actions/setup-go@main
-        with:
-          go-version: 1.20.0
-        id: go
-
-      - name: Setup docker scan
-        run: |
-          mkdir -p ~/.docker/cli-plugins && \
-          curl https://github.com/docker/scan-cli-plugin/releases/latest/download/docker-scan_linux_amd64 -L -s -S -o ~/.docker/cli-plugins/docker-scan &&\
-          chmod +x ~/.docker/cli-plugins/docker-scan
-
-      - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v2
-      
-      - name: Code checkout
-        uses: actions/checkout@master
-
-      - uses: actions/cache@v3
-        with:
-          path: gocache-for-docker
-          key: gocache-docker-${{ runner.os }}-${{ steps.go.outputs.go-version }}-${{ hashFiles('go.mod') }}
-
-      - name: build & publish
-        run: |
-          docker scan --severity=medium --login --token "$SNYK_TOKEN" --accept-license
-          LATEST_TAG=nightly PKG_TAG=nightly make publish
-        env: 
-          SNYK_TOKEN: ${{ secrets.SNYK_AUTH_TOKEN }}

.github/workflows/sync-docs.yml

@@ -0,0 +1,53 @@
+name: publish-docs
+on:
+  push:
+    branches:
+      - 'master'
+    paths:
+      - 'docs/**'
+  workflow_dispatch: {}
+permissions:
+  contents: read  # This is required for actions/checkout and to commit back image update
+  deployments: write
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Code checkout
+        uses: actions/checkout@v3
+        with:
+          path: main
+      - name: Checkout private code
+        uses: actions/checkout@v3
+        with:
+          repository: VictoriaMetrics/vmdocs
+          token: ${{ secrets.VM_BOT_GH_TOKEN }}
+          path: docs
+
+      - name: Import GPG key
+        uses: crazy-max/ghaction-import-gpg@v5
+        with:
+          gpg_private_key: ${{ secrets.VM_BOT_GPG_PRIVATE_KEY }}
+          passphrase: ${{ secrets.VM_BOT_PASSPHRASE }}
+          git_user_signingkey: true
+          git_commit_gpgsign: true
+          workdir: docs
+      - name: Set short git commit SHA
+        id: vars
+        run: |
+          calculatedSha=$(git rev-parse --short ${{ github.sha }})
+          echo "short_sha=$calculatedSha" >> $GITHUB_OUTPUT
+        working-directory: main
+
+      - name: update code and commit
+        run: |
+          rm -rf content
+          cp -r ../main/docs content
+          make clean-after-copy
+          git config --global user.name "${{ steps.import-gpg.outputs.email }}"
+          git config --global user.email "${{ steps.import-gpg.outputs.email }}"
+          git add .
+          git commit -S -m "sync docs with VictoriaMetrics/VictoriaMetrics commit: ${{ steps.vars.outputs.short_sha }}"
+          git push
+        working-directory: docs

.github/workflows/update-sandbox.yml

@@ -0,0 +1,80 @@
+name: sandbox-release
+on:
+  release:
+    types: [published]
+permissions:
+  contents: write
+jobs:
+  deploy-sandbox:
+    runs-on: ubuntu-latest
+    steps:
+      - name: check inputs
+        if: github.event.release.tag_name == ''
+        run: exit 1
+    
+      - name: Check out code
+        uses: actions/checkout@v3
+        with:
+          repository: VictoriaMetrics/ops
+          token: ${{ secrets.VM_BOT_GH_TOKEN }}
+
+      - name: Import GPG key
+        id: import-gpg
+        uses: crazy-max/ghaction-import-gpg@v5
+        with:
+          gpg_private_key: ${{ secrets.VM_BOT_GPG_PRIVATE_KEY }}
+          passphrase: ${{ secrets.VM_BOT_PASSPHRASE }}
+          git_user_signingkey: true
+          git_commit_gpgsign: true
+
+      - name: update image tag
+        uses: fjogeleit/yaml-update-action@main
+        with:
+          valueFile: 'gcp-test/sandbox/manifests/benchmark-vm/vmcluster.yaml'
+          commitChange: false
+          createPR: false
+          changes: |
+            {
+              "gcp-test/sandbox/manifests/benchmark-vm/vmcluster.yaml": {
+                "spec.vminsert.image.tag": "${{ github.event.release.tag_name }}-enterprise-cluster",
+                "spec.vmselect.image.tag": "${{ github.event.release.tag_name }}-enterprise-cluster",
+                "spec.vmstorage.image.tag": "${{ github.event.release.tag_name }}-enterprise-cluster"
+              },
+              "gcp-test/sandbox/manifests/benchmark-vm/vmsingle.yaml": {
+                "spec.image.tag": "${{ github.event.release.tag_name }}-enterprise"
+              },
+              "gcp-test/sandbox/manifests/monitoring/monitoring-vmagent.yaml": {
+                "spec.image.tag": "${{ github.event.release.tag_name }}"
+              },
+              "gcp-test/sandbox/manifests/monitoring/monitoring-vmcluster.yaml": {
+                "spec.vminsert.image.tag": "${{ github.event.release.tag_name }}-enterprise-cluster",
+                "spec.vmselect.image.tag": "${{ github.event.release.tag_name }}-enterprise-cluster",
+                "spec.vmstorage.image.tag": "${{ github.event.release.tag_name }}-enterprise-cluster"
+              },
+              "gcp-test/sandbox/manifests/monitoring/vmalert.yaml": {
+                "spec.image.tag": "${{ github.event.release.tag_name }}-enterprise"
+              }
+            }
+
+      - name: commit changes
+        run: |
+          git config --global user.name "${{ steps.import-gpg.outputs.email }}"
+          git config --global user.email "${{ steps.import-gpg.outputs.email }}"
+          git add .
+          git commit -S -m "Deploy image tag ${RELEASE_TAG} to sandbox"
+        env:
+          RELEASE_TAG: ${{ github.event.release.tag_name }}
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v5
+        with:
+          author: ${{ github.actor }} <${{ github.actor }}@users.noreply.github.com>
+          branch: release-automation
+          token: ${{ secrets.VM_BOT_GH_TOKEN }}
+          delete-branch: true
+          title: "release ${{ github.event.release.tag_name }}"
+          body: |
+            Release [${{ github.event.release.tag_name }}](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/${{ github.event.release.tag_name }}) to sandbox
+        
+            > Auto-generated by `Github Actions Bot`
+    

.gitignore

@@ -8,6 +8,7 @@
 *.test
 *.swp
 /gocache-for-docker
+/victoria-logs-data
 /victoria-metrics-data
 /vmagent-remotewrite-data
 /vmstorage-data
@@ -20,4 +21,4 @@
 Gemfile.lock
 /_site
 _site
-*.tmp
+*.tmp

.golangci.yml

@@ -1,14 +1,18 @@
 run:
   timeout: 2m
 
-enable:
+linters:
+  enable:
   - revive
 
 issues:
   exclude-rules:
-    - linters:
-      - staticcheck
-      text: "SA(4003|1019|5011):"
+  - linters:
+    - staticcheck
+    text: "SA(4003|1019|5011):"
+  include:
+  - EXC0012
+  - EXC0014
 
 linters-settings:
   errcheck:

Makefile

@@ -21,6 +21,7 @@ include package/release/Makefile
 
 all: \
 	victoria-metrics-prod \
+	victoria-logs-prod \
 	vmagent-prod \
 	vmalert-prod \
 	vmauth-prod \
@@ -31,8 +32,9 @@ all: \
 clean:
 	rm -rf bin/*
 
-publish: docker-scan \
+publish: package-base \
 	publish-victoria-metrics \
+	publish-victoria-logs \
 	publish-vmagent \
 	publish-vmalert \
 	publish-vmauth \
@@ -42,6 +44,7 @@ publish: docker-scan \
 
 package: \
 	package-victoria-metrics \
+	package-victoria-logs \
 	package-vmagent \
 	package-vmalert \
 	package-vmauth \
@@ -141,6 +144,8 @@ vmutils-windows-amd64: \
 	vmagent-windows-amd64 \
 	vmalert-windows-amd64 \
 	vmauth-windows-amd64 \
+	vmbackup-windows-amd64 \
+	vmrestore-windows-amd64 \
 	vmctl-windows-amd64
 
 victoria-metrics-crossbuild: \
@@ -176,6 +181,7 @@ publish-release:
 
 release: \
 	release-victoria-metrics \
+	release-victoria-logs \
 	release-vmutils
 
 release-victoria-metrics: \
@@ -186,9 +192,9 @@ release-victoria-metrics: \
 	release-victoria-metrics-darwin-amd64 \
 	release-victoria-metrics-darwin-arm64 \
 	release-victoria-metrics-freebsd-amd64 \
-	release-victoria-metrics-openbsd-amd64
+	release-victoria-metrics-openbsd-amd64 \
+	release-victoria-metrics-windows-amd64
 
-# adds i386 arch
 release-victoria-metrics-linux-386:
 	GOOS=linux GOARCH=386 $(MAKE) release-victoria-metrics-goos-goarch
 
@@ -213,6 +219,9 @@ release-victoria-metrics-freebsd-amd64:
 release-victoria-metrics-openbsd-amd64:
 	GOOS=openbsd GOARCH=amd64 $(MAKE) release-victoria-metrics-goos-goarch
 
+release-victoria-metrics-windows-amd64:
+	GOARCH=amd64 $(MAKE) release-victoria-metrics-windows-goarch
+
 release-victoria-metrics-goos-goarch: victoria-metrics-$(GOOS)-$(GOARCH)-prod
 	cd bin && \
 		tar --transform="flags=r;s|-$(GOOS)-$(GOARCH)||" -czf victoria-metrics-$(GOOS)-$(GOARCH)-$(PKG_TAG).tar.gz \
@@ -222,6 +231,73 @@ release-victoria-metrics-goos-goarch: victoria-metrics-$(GOOS)-$(GOARCH)-prod
 			| sed s/-$(GOOS)-$(GOARCH)-prod/-prod/ > victoria-metrics-$(GOOS)-$(GOARCH)-$(PKG_TAG)_checksums.txt
 	cd bin && rm -rf victoria-metrics-$(GOOS)-$(GOARCH)-prod
 
+release-victoria-metrics-windows-goarch: victoria-metrics-windows-$(GOARCH)-prod
+	cd bin && \
+		zip victoria-metrics-windows-$(GOARCH)-$(PKG_TAG).zip \
+			victoria-metrics-windows-$(GOARCH)-prod.exe \
+		&& sha256sum victoria-metrics-windows-$(GOARCH)-$(PKG_TAG).zip \
+			victoria-metrics-windows-$(GOARCH)-prod.exe \
+			> victoria-metrics-windows-$(GOARCH)-$(PKG_TAG)_checksums.txt
+	cd bin && rm -rf \
+		victoria-metrics-windows-$(GOARCH)-prod.exe
+
+release-victoria-logs: \
+	release-victoria-logs-linux-386 \
+	release-victoria-logs-linux-amd64 \
+	release-victoria-logs-linux-arm \
+	release-victoria-logs-linux-arm64 \
+	release-victoria-logs-darwin-amd64 \
+	release-victoria-logs-darwin-arm64 \
+	release-victoria-logs-freebsd-amd64 \
+	release-victoria-logs-openbsd-amd64 \
+	release-victoria-logs-windows-amd64
+
+release-victoria-logs-linux-386:
+	GOOS=linux GOARCH=386 $(MAKE) release-victoria-logs-goos-goarch
+
+release-victoria-logs-linux-amd64:
+	GOOS=linux GOARCH=amd64 $(MAKE) release-victoria-logs-goos-goarch
+
+release-victoria-logs-linux-arm:
+	GOOS=linux GOARCH=arm $(MAKE) release-victoria-logs-goos-goarch
+
+release-victoria-logs-linux-arm64:
+	GOOS=linux GOARCH=arm64 $(MAKE) release-victoria-logs-goos-goarch
+
+release-victoria-logs-darwin-amd64:
+	GOOS=darwin GOARCH=amd64 $(MAKE) release-victoria-logs-goos-goarch
+
+release-victoria-logs-darwin-arm64:
+	GOOS=darwin GOARCH=arm64 $(MAKE) release-victoria-logs-goos-goarch
+
+release-victoria-logs-freebsd-amd64:
+	GOOS=freebsd GOARCH=amd64 $(MAKE) release-victoria-logs-goos-goarch
+
+release-victoria-logs-openbsd-amd64:
+	GOOS=openbsd GOARCH=amd64 $(MAKE) release-victoria-logs-goos-goarch
+
+release-victoria-logs-windows-amd64:
+	GOARCH=amd64 $(MAKE) release-victoria-logs-windows-goarch
+
+release-victoria-logs-goos-goarch: victoria-logs-$(GOOS)-$(GOARCH)-prod
+	cd bin && \
+		tar --transform="flags=r;s|-$(GOOS)-$(GOARCH)||" -czf victoria-logs-$(GOOS)-$(GOARCH)-$(PKG_TAG).tar.gz \
+			victoria-logs-$(GOOS)-$(GOARCH)-prod \
+		&& sha256sum victoria-logs-$(GOOS)-$(GOARCH)-$(PKG_TAG).tar.gz \
+			victoria-logs-$(GOOS)-$(GOARCH)-prod \
+			| sed s/-$(GOOS)-$(GOARCH)-prod/-prod/ > victoria-logs-$(GOOS)-$(GOARCH)-$(PKG_TAG)_checksums.txt
+	cd bin && rm -rf victoria-logs-$(GOOS)-$(GOARCH)-prod
+
+release-victoria-logs-windows-goarch: victoria-logs-windows-$(GOARCH)-prod
+	cd bin && \
+		zip victoria-logs-windows-$(GOARCH)-$(PKG_TAG).zip \
+			victoria-logs-windows-$(GOARCH)-prod.exe \
+		&& sha256sum victoria-logs-windows-$(GOARCH)-$(PKG_TAG).zip \
+			victoria-logs-windows-$(GOARCH)-prod.exe \
+			> victoria-logs-windows-$(GOARCH)-$(PKG_TAG)_checksums.txt
+	cd bin && rm -rf \
+		victoria-logs-windows-$(GOARCH)-prod.exe
+
 release-vmutils: \
 	release-vmutils-linux-386 \
 	release-vmutils-linux-amd64 \
@@ -295,26 +371,33 @@ release-vmutils-windows-goarch: \
 	vmagent-windows-$(GOARCH)-prod \
 	vmalert-windows-$(GOARCH)-prod \
 	vmauth-windows-$(GOARCH)-prod \
+	vmbackup-windows-$(GOARCH)-prod \
+	vmrestore-windows-$(GOARCH)-prod \
 	vmctl-windows-$(GOARCH)-prod
 	cd bin && \
 		zip vmutils-windows-$(GOARCH)-$(PKG_TAG).zip \
 			vmagent-windows-$(GOARCH)-prod.exe \
 			vmalert-windows-$(GOARCH)-prod.exe \
 			vmauth-windows-$(GOARCH)-prod.exe \
+			vmbackup-windows-$(GOARCH)-prod.exe \
+			vmrestore-windows-$(GOARCH)-prod.exe \
 			vmctl-windows-$(GOARCH)-prod.exe \
 		&& sha256sum vmutils-windows-$(GOARCH)-$(PKG_TAG).zip \
 			vmagent-windows-$(GOARCH)-prod.exe \
 			vmalert-windows-$(GOARCH)-prod.exe \
 			vmauth-windows-$(GOARCH)-prod.exe \
+			vmbackup-windows-$(GOARCH)-prod.exe \
+			vmrestore-windows-$(GOARCH)-prod.exe \
 			vmctl-windows-$(GOARCH)-prod.exe \
 			> vmutils-windows-$(GOARCH)-$(PKG_TAG)_checksums.txt
 	cd bin && rm -rf \
 		vmagent-windows-$(GOARCH)-prod.exe \
 		vmalert-windows-$(GOARCH)-prod.exe \
 		vmauth-windows-$(GOARCH)-prod.exe \
+		vmbackup-windows-$(GOARCH)-prod.exe \
+		vmrestore-windows-$(GOARCH)-prod.exe \
 		vmctl-windows-$(GOARCH)-prod.exe
 
-
 pprof-cpu:
 	go tool pprof -trim_path=github.com/VictoriaMetrics/VictoriaMetrics@ $(PPROF_FILE)
 
@@ -380,7 +463,7 @@ golangci-lint: install-golangci-lint
 	golangci-lint run
 
 install-golangci-lint:
-	which golangci-lint || curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(shell go env GOPATH)/bin v1.51.1
+	which golangci-lint || curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(shell go env GOPATH)/bin v1.51.2
 
 govulncheck: install-govulncheck
 	govulncheck ./...
@@ -395,27 +478,39 @@ check-licenses: install-wwhrd
 	wwhrd check -f .wwhrd.yml
 
 copy-docs:
-	echo '' > ${DST}
+# The 'printf' function is used instead of 'echo' or 'echo -e' to handle line breaks (e.g. '\n') in the same way on different operating systems (MacOS/Ubuntu Linux/Arch Linux) and their shells (bash/sh/zsh/fish).
+# For details, see https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4548#issue-1782796419 and https://stackoverflow.com/questions/8467424/echo-newline-in-bash-prints-literal-n
+	echo "---" > ${DST}
 	@if [ ${ORDER} -ne 0 ]; then \
-		echo "---\nsort: ${ORDER}\n---\n" > ${DST}; \
+		echo "sort: ${ORDER}" >> ${DST}; \
+		echo "weight: ${ORDER}" >> ${DST}; \
+		printf "menu:\n  docs:\n    parent: 'victoriametrics'\n    weight: ${ORDER}\n" >> ${DST}; \
 	fi
+
+	echo "title: ${TITLE}" >> ${DST}
+	@if [ ${OLD_URL} ]; then \
+		printf "aliases:\n  - ${OLD_URL}\n" >> ${DST}; \
+	fi
+	echo "---" >> ${DST}
 	cat ${SRC} >> ${DST}
 	sed -i='.tmp' 's/<img src=\"docs\//<img src=\"/' ${DST}
 	rm -rf docs/*.tmp
 
-# Copies docs for all components and adds the order tag.
-# For ORDER=0 it adds no order tag.
+# Copies docs for all components and adds the order/weight tag, title, menu position and alias with the backward compatible link for the old site.
+# For ORDER=0 it adds no order tag/weight tag.
+# FOR OLD_URL - relative link, used for backward compatibility with the link from documentation based on GitHub pages (old one)
+# FOR OLD_URL='' it adds no alias, it should be empty for every new page, don't change it for already existing links.
 # Images starting with <img src="docs/ are replaced with <img src="
-# Cluster docs are supposed to be ordered as 9th.
+# Cluster docs are supposed to be ordered as 2nd.
 # The rest of docs is ordered manually.
 docs-sync:
-	SRC=README.md DST=docs/README.md ORDER=0 $(MAKE) copy-docs
-	SRC=README.md DST=docs/Single-server-VictoriaMetrics.md ORDER=1 $(MAKE) copy-docs
-	SRC=app/vmagent/README.md DST=docs/vmagent.md ORDER=3 $(MAKE) copy-docs
-	SRC=app/vmalert/README.md DST=docs/vmalert.md ORDER=4 $(MAKE) copy-docs
-	SRC=app/vmauth/README.md DST=docs/vmauth.md ORDER=5 $(MAKE) copy-docs
-	SRC=app/vmbackup/README.md DST=docs/vmbackup.md ORDER=6 $(MAKE) copy-docs
-	SRC=app/vmrestore/README.md DST=docs/vmrestore.md ORDER=7 $(MAKE) copy-docs
-	SRC=app/vmctl/README.md DST=docs/vmctl.md ORDER=8 $(MAKE) copy-docs
-	SRC=app/vmgateway/README.md DST=docs/vmgateway.md ORDER=9 $(MAKE) copy-docs
-	SRC=app/vmbackupmanager/README.md DST=docs/vmbackupmanager.md ORDER=10 $(MAKE) copy-docs
+	SRC=README.md DST=docs/README.md OLD_URL='' ORDER=0 TITLE=VictoriaMetrics $(MAKE) copy-docs
+	SRC=README.md DST=docs/Single-server-VictoriaMetrics.md OLD_URL='/Single-server-VictoriaMetrics.html' TITLE=VictoriaMetrics ORDER=1 $(MAKE) copy-docs
+	SRC=app/vmagent/README.md DST=docs/vmagent.md OLD_URL='/vmagent.html' ORDER=3 TITLE=vmagent $(MAKE) copy-docs
+	SRC=app/vmalert/README.md DST=docs/vmalert.md OLD_URL='/vmalert.html' ORDER=4 TITLE=vmalert $(MAKE) copy-docs
+	SRC=app/vmauth/README.md DST=docs/vmauth.md OLD_URL='/vmauth.html' ORDER=5 TITLE=vmauth $(MAKE) copy-docs
+	SRC=app/vmbackup/README.md DST=docs/vmbackup.md OLD_URL='/vmbackup.html' ORDER=6 TITLE=vmbackup $(MAKE) copy-docs
+	SRC=app/vmrestore/README.md DST=docs/vmrestore.md OLD_URL='/vmrestore.html' ORDER=7 TITLE=vmrestore $(MAKE) copy-docs
+	SRC=app/vmctl/README.md DST=docs/vmctl.md OLD_URL='/vmctl.html' ORDER=8 TITLE=vmctl $(MAKE) copy-docs
+	SRC=app/vmgateway/README.md DST=docs/vmgateway.md OLD_URL='/vmgateway.html' ORDER=9 TITLE=vmgateway $(MAKE) copy-docs
+	SRC=app/vmbackupmanager/README.md DST=docs/vmbackupmanager.md OLD_URL='/vmbackupmanager.html' ORDER=10 TITLE=vmbackupmanager $(MAKE) copy-docs

README.md

@@ -2,6 +2,7 @@
 
 [![Latest Release](https://img.shields.io/github/release/VictoriaMetrics/VictoriaMetrics.svg?style=flat-square)](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/latest)
 [![Docker Pulls](https://img.shields.io/docker/pulls/victoriametrics/victoria-metrics.svg?maxAge=604800)](https://hub.docker.com/r/victoriametrics/victoria-metrics)
+[![victoriametrics](https://snapcraft.io/victoriametrics/badge.svg)](https://snapcraft.io/victoriametrics)
 [![Slack](https://img.shields.io/badge/join%20slack-%23victoriametrics-brightgreen.svg)](https://slack.victoriametrics.com/)
 [![GitHub license](https://img.shields.io/github/license/VictoriaMetrics/VictoriaMetrics.svg)](https://github.com/VictoriaMetrics/VictoriaMetrics/blob/master/LICENSE)
 [![Go Report](https://goreportcard.com/badge/github.com/VictoriaMetrics/VictoriaMetrics)](https://goreportcard.com/report/github.com/VictoriaMetrics/VictoriaMetrics)
@@ -15,14 +16,16 @@ VictoriaMetrics is a fast, cost-effective and scalable monitoring solution and t
 VictoriaMetrics is available in [binary releases](https://github.com/VictoriaMetrics/VictoriaMetrics/releases),
 [Docker images](https://hub.docker.com/r/victoriametrics/victoria-metrics/), [Snap packages](https://snapcraft.io/victoriametrics)
 and [source code](https://github.com/VictoriaMetrics/VictoriaMetrics). 
-Just download [the latest version of VictoriaMetrics](https://docs.victoriametrics.com/CHANGELOG.html)
-and follow [these instructions](https://docs.victoriametrics.com/Quick-Start.html).
 
 The cluster version of VictoriaMetrics is available [here](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html).
 
 Learn more about [key concepts](https://docs.victoriametrics.com/keyConcepts.html) of VictoriaMetrics and follow the 
 [quick start guide](https://docs.victoriametrics.com/Quick-Start.html) for a better experience.
 
+There is also user-friendly database for logs - [VictoriaLogs](https://docs.victoriametrics.com/VictoriaLogs/).
+
+If you have questions about VictoriaMetrics, then feel free asking them at [VictoriaMetrics community Slack chat](https://slack.victoriametrics.com/).
+
 [Contact us](mailto:info@victoriametrics.com) if you need enterprise support for VictoriaMetrics. 
 See [features available in enterprise package](https://docs.victoriametrics.com/enterprise.html).
 Enterprise binaries can be downloaded and evaluated for free 
@@ -39,7 +42,8 @@ VictoriaMetrics has the following prominent features:
 * It can be used as long-term storage for Prometheus. See [these docs](#prometheus-setup) for details.
 * It can be used as a drop-in replacement for Prometheus in Grafana, because it supports [Prometheus querying API](#prometheus-querying-api-usage).
 * It can be used as a drop-in replacement for Graphite in Grafana, because it supports [Graphite API](#graphite-api-usage).
-* It features easy setup and operation:
+  VictoriaMetrics allows reducing infrastructure costs by more than 10x comparing to Graphite - see [this case study](https://docs.victoriametrics.com/CaseStudies.html#grammarly).
+* It is easy to setup and operate:
   * VictoriaMetrics consists of a single [small executable](https://medium.com/@valyala/stripping-dependency-bloat-in-victoriametrics-docker-image-983fb5912b0d)
     without external dependencies.
   * All the configuration is done via explicit command-line flags with reasonable defaults.
@@ -82,6 +86,7 @@ VictoriaMetrics has the following prominent features:
   * [Arbitrary CSV data](#how-to-import-csv-data).
   * [Native binary format](#how-to-import-data-in-native-format).
   * [DataDog agent or DogStatsD](#how-to-send-data-from-datadog-agent).
+  * [OpenTelemetry metrics format](#sending-data-via-opentelemetry).
 * It supports powerful [stream aggregation](https://docs.victoriametrics.com/stream-aggregation.html), which can be used as a [statsd](https://github.com/statsd/statsd) alternative.
 * It supports metrics [relabeling](#relabeling).
 * It can deal with [high cardinality issues](https://docs.victoriametrics.com/FAQ.html#what-is-high-cardinality) and
@@ -105,6 +110,7 @@ Case studies:
 * [Brandwatch](https://docs.victoriametrics.com/CaseStudies.html#brandwatch)
 * [CERN](https://docs.victoriametrics.com/CaseStudies.html#cern)
 * [COLOPL](https://docs.victoriametrics.com/CaseStudies.html#colopl)
+* [Dig Security](https://docs.victoriametrics.com/CaseStudies.html#dig-security)
 * [Fly.io](https://docs.victoriametrics.com/CaseStudies.html#flyio)
 * [German Research Center for Artificial Intelligence](https://docs.victoriametrics.com/CaseStudies.html#german-research-center-for-artificial-intelligence)
 * [Grammarly](https://docs.victoriametrics.com/CaseStudies.html#grammarly)
@@ -113,6 +119,7 @@ Case studies:
 * [MHI Vestas Offshore Wind](https://docs.victoriametrics.com/CaseStudies.html#mhi-vestas-offshore-wind)
 * [Razorpay](https://docs.victoriametrics.com/CaseStudies.html#razorpay)
 * [Percona](https://docs.victoriametrics.com/CaseStudies.html#percona)
+* [Roblox](https://docs.victoriametrics.com/CaseStudies.html#roblox)
 * [Sensedia](https://docs.victoriametrics.com/CaseStudies.html#sensedia)
 * [Smarkets](https://docs.victoriametrics.com/CaseStudies.html#smarkets)
 * [Synthesio](https://docs.victoriametrics.com/CaseStudies.html#synthesio)
@@ -125,15 +132,26 @@ See also [articles and slides about VictoriaMetrics from our users](https://docs
 
 ## Operation
 
-### How to start VictoriaMetrics
+### Install
 
-Just download [VictoriaMetrics executable](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) or [Docker image](https://hub.docker.com/r/victoriametrics/victoria-metrics/) and start it with the desired command-line flags.
+To quickly try VictoriaMetrics, just download [VictoriaMetrics executable](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) or [Docker image](https://hub.docker.com/r/victoriametrics/victoria-metrics/) and start it with the desired command-line flags.
 See also [QuickStart guide](https://docs.victoriametrics.com/Quick-Start.html) for additional information.
 
+VictoriaMetrics can also be installed via these installation methods:
+
+* [Helm charts for single-node and cluster versions of VictoriaMetrics](https://github.com/VictoriaMetrics/helm-charts).
+* [Kubernetes operator for VictoriaMetrics](https://github.com/VictoriaMetrics/operator).
+* [Ansible role for installing cluster VictoriaMetrics (by VictoriaMetrics)](https://github.com/VictoriaMetrics/ansible-playbooks).
+* [Ansible role for installing cluster VictoriaMetrics (by community)](https://github.com/Slapper/ansible-victoriametrics-cluster-role).
+* [Ansible role for installing single-node VictoriaMetrics (by community)](https://github.com/dreamteam-gg/ansible-victoriametrics-role).
+* [Snap package for VictoriaMetrics](https://snapcraft.io/victoriametrics).
+
+### How to start VictoriaMetrics
+
 The following command-line flags are used the most:
 
 * `-storageDataPath` - VictoriaMetrics stores all the data in this directory. Default path is `victoria-metrics-data` in the current working directory.
-* `-retentionPeriod` - retention for stored data. Older data is automatically deleted. Default retention is 1 month. See [the Retention section](#retention) for more details.
+* `-retentionPeriod` - retention for stored data. Older data is automatically deleted. Default retention is 1 month. The minimum retention period is 24h or 1d. See [the Retention section](#retention) for more details.
 
 Other flags have good enough default values, so set them only if you really need this. Pass `-help` to see [all the available flags with description and default values](#list-of-command-line-flags).
 
@@ -188,7 +206,7 @@ Changing scrape configuration is possible with text editor:
 vi $SNAP_DATA/var/snap/victoriametrics/current/etc/victoriametrics-scrape-config.yaml
 ```
 
-After changes were made, trigger config re-read with the command `curl 127.0.0.1:8248/-/reload`.
+After changes were made, trigger config re-read with the command `curl 127.0.0.1:8428/-/reload`.
 
 ## Prometheus setup
 
@@ -268,7 +286,11 @@ http://<victoriametrics-addr>:8428
 
 Substitute `<victoriametrics-addr>` with the hostname or IP address of VictoriaMetrics.
 
-Then build graphs and dashboards for the created datasource using [PromQL](https://prometheus.io/docs/prometheus/latest/querying/basics/) or [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html).
+Then build graphs and dashboards for the created datasource using [PromQL](https://prometheus.io/docs/prometheus/latest/querying/basics/)
+or [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html).
+
+Alternatively, use VictoriaMetrics [datasource plugin](https://github.com/VictoriaMetrics/grafana-datasource) with support of extra features. 
+See more in [description](https://github.com/VictoriaMetrics/grafana-datasource#victoriametrics-data-source-for-grafana).
 
 ## How to upgrade VictoriaMetrics
 
@@ -289,13 +311,22 @@ Prometheus doesn't drop data during VictoriaMetrics restart. See [this article](
 ## vmui
 
 VictoriaMetrics provides UI for query troubleshooting and exploration. The UI is available at `http://victoriametrics:8428/vmui`.
-The UI allows exploring query results via graphs and tables.
-It also provides the following features:
+The UI allows exploring query results via graphs and tables. It also provides the following features:
 
-- [metrics explorer](#metrics-explorer)
-- [cardinality explorer](#cardinality-explorer)
-- [query tracer](#query-tracing)
-- [top queries explorer](#top-queries)
+- Explore:
+  - [Metrics explorer](#metrics-explorer) - automatically builds graphs for selected metrics; 
+  - [Cardinality explorer](#cardinality-explorer) - stats about existing metrics in TSDB;
+  - [Top queries](#top-queries) - shows most frequently executed queries;
+  - [Active queries](#active-queries) - shows currently executed queries;
+- Tools:
+  - [Trace analyzer](#query-tracing) - playground for loading query traces in JSON format; 
+  - [WITH expressions playground](https://play.victoriametrics.com/select/accounting/1/6a716b0f-38bc-4856-90ce-448fd713e3fe/prometheus/graph/#/expand-with-exprs) - test how WITH expressions work; 
+  - [Metric relabel debugger](https://play.victoriametrics.com/select/accounting/1/6a716b0f-38bc-4856-90ce-448fd713e3fe/prometheus/graph/#/relabeling) - playground for [relabeling](#relabeling) configs.
+
+VMUI automatically switches from graph view to heatmap view when the query returns [histogram](https://docs.victoriametrics.com/keyConcepts.html#histogram) buckets
+(both [Prometheus histograms](https://prometheus.io/docs/concepts/metric_types/#histogram)
+and [VictoriaMetrics histograms](https://valyala.medium.com/improving-histogram-usability-for-prometheus-and-grafana-bc7e5df0e350) are supported).
+Try, for example, [this query](https://play.victoriametrics.com/select/accounting/1/6a716b0f-38bc-4856-90ce-448fd713e3fe/prometheus/graph/#/?g0.expr=sum%28rate%28vm_promscrape_scrape_duration_seconds_bucket%29%29+by+%28vmrange%29&g0.range_input=24h&g0.end_input=2023-04-10T17%3A46%3A12&g0.relative_time=last_24_hours&g0.step_input=31m).
 
 Graphs in `vmui` support scrolling and zooming:
 
@@ -307,9 +338,12 @@ Query history can be navigated by holding `Ctrl` (or `Cmd` on MacOS) and pressin
 
 Multi-line queries can be entered by pressing `Shift-Enter` in query input field.
 
-When querying the [backfilled data](https://docs.victoriametrics.com/#backfilling) or during [query troubleshooting](https://docs.victoriametrics.com/Troubleshooting.html#unexpected-query-results), it may be useful disabling response cache by clicking `Disable cache` checkbox.
+When querying the [backfilled data](https://docs.victoriametrics.com/#backfilling)
+or during [query troubleshooting](https://docs.victoriametrics.com/Troubleshooting.html#unexpected-query-results),
+it may be useful disabling response cache by clicking `Disable cache` checkbox.
 
-VMUI automatically adjusts the interval between datapoints on the graph depending on the horizontal resolution and on the selected time range. The step value can be customized by changing `Step value` input.
+VMUI automatically adjusts the interval between datapoints on the graph depending on the horizontal resolution and on the selected time range.
+The step value can be customized by changing `Step value` input.
 
 VMUI allows investigating correlations between multiple queries on the same graph. Just click `Add Query` button,
 enter an additional query in the newly appeared input field and press `Enter`.
@@ -328,15 +362,24 @@ See the [example VMUI at VictoriaMetrics playground](https://play.victoriametric
 * queries with the biggest average execution duration;
 * queries that took the most summary time for execution.
 
+## Active queries
+
+[VMUI](#vmui) provides `active queries` tab, which shows currently execute queries.
+It provides the following information per each query:
+
+- The query itself, together with the time range and step args passed to [/api/v1/query_range](https://docs.victoriametrics.com/keyConcepts.html#range-query).
+- The duration of the query execution.
+- The client address, who initiated the query execution.
+
 ## Metrics explorer
 
 [VMUI](#vmui) provides an ability to explore metrics exported by a particular `job` / `instance` in the following way:
 
 1. Open the `vmui` at `http://victoriametrics:8428/vmui/`.
-2. Click the `Explore metrics` tab.
-3. Select the `job` you want to explore.
-4. Optionally select the `instance` for the selected job to explore.
-5. Select metrics you want to explore and compare.
+1. Click the `Explore metrics` tab.
+1. Select the `job` you want to explore.
+1. Optionally select the `instance` for the selected job to explore.
+1. Select metrics you want to explore and compare.
 
 It is possible to change the selected time range for the graphs in the top right corner.
 
@@ -353,12 +396,17 @@ VictoriaMetrics provides an ability to explore time series cardinality at `Explo
   may show lower than expected number of unique label values for labels with small number of unique values.
   This is because of [implementation limits](https://github.com/VictoriaMetrics/VictoriaMetrics/blob/5a6e617b5e41c9170e7c562aecd15ee0c901d489/app/vmselect/netstorage/netstorage.go#L1039-L1045).
 
-By default cardinality explorer analyzes time series for the current date. It provides the ability to select different day at the top right corner.
-By default all the time series for the selected date are analyzed. It is possible to narrow down the analysis to series
+By default, cardinality explorer analyzes time series for the current date. It provides the ability to select different day at the top right corner.
+By default, all the time series for the selected date are analyzed. It is possible to narrow down the analysis to series
 matching the specified [series selector](https://prometheus.io/docs/prometheus/latest/querying/basics/#time-series-selectors).
 
 Cardinality explorer is built on top of [/api/v1/status/tsdb](#tsdb-stats).
 
+In [cluster version of VictoriaMetrics](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html) each vmstorage tracks the stored time series individually.
+vmselect requests stats via [/api/v1/status/tsdb](#tsdb-stats) API from each vmstorage node and merges the results by summing per-series stats.
+This may lead to inflated values when samples for the same time series are spread across multiple vmstorage nodes
+due to [replication](#replication) or [rerouting](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html?highlight=re-routes#cluster-availability).
+
 See [cardinality explorer playground](https://play.victoriametrics.com/select/accounting/1/6a716b0f-38bc-4856-90ce-448fd713e3fe/prometheus/graph/#/cardinality).
 See the example of using the cardinality explorer [here](https://victoriametrics.com/blog/cardinality-explorer/).
 
@@ -374,7 +422,7 @@ Prometheus doesn't drop data during VictoriaMetrics restart. See [this article](
 
 ## How to scrape Prometheus exporters such as [node-exporter](https://github.com/prometheus/node_exporter)
 
-VictoriaMetrics can be used as drop-in replacement for Prometheus for scraping targets configured in `prometheus.yml` config file according to [the specification](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#configuration-file). Just set `-promscrape.config` command-line flag to the path to `prometheus.yml` config - and VictoriaMetrics should start scraping the configured targets.
+VictoriaMetrics can be used as drop-in replacement for Prometheus for scraping targets configured in `prometheus.yml` config file according to [the specification](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#configuration-file). Just set `-promscrape.config` command-line flag to the path to `prometheus.yml` config - and VictoriaMetrics should start scraping the configured targets. If the provided configuration file contains [unsupported options](https://docs.victoriametrics.com/vmagent.html#unsupported-prometheus-config-sections), then either delete them from the file or just pass `-promscrape.config.strictParse=false` command-line flag to VictoriaMetrics, so it will ignore unsupported options.
 
 The file pointed by `-promscrape.config` may contain `%{ENV_VAR}` placeholders, which are substituted by the corresponding `ENV_VAR` environment variable values.
 
@@ -411,7 +459,7 @@ DD_DD_URL=http://victoriametrics:8428/datadog
 
 _Choose correct URL for VictoriaMetrics [here](https://docs.victoriametrics.com/url-examples.html#datadog)._
 
-To configure DataDog agent via [configuration file](https://docs.datadoghq.com/agent/guide/agent-configuration-files)
+To configure DataDog agent via [configuration file](https://github.com/DataDog/datadog-agent/blob/878600ef7a55c5ef0efb41ed0915f020cf7e3bd0/pkg/config/config_template.yaml#L33)
 add the following line:
 
 <div class="with-copy" markdown="1">
@@ -439,7 +487,8 @@ Run DataDog using the following ENV variable with VictoriaMetrics as additional
 <div class="with-copy" markdown="1">
 
 ```
-DD_ADDITIONAL_ENDPOINTS='{\"http://victoriametrics:8428/datadog\"}'
+DD_ADDITIONAL_ENDPOINTS='{\"http://victoriametrics:8428/datadog\": [\"apikey\"]}'
+
 ```
 
 </div>
@@ -453,7 +502,9 @@ add the following line:
 <div class="with-copy" markdown="1">
 
 ```
-additional_endpoints: http://victoriametrics:8428/datadog
+additional_endpoints:
+  "http://victoriametrics:8428/datadog":
+  - apikey
 ```
 
 </div>
@@ -499,8 +550,10 @@ and stream plain InfluxDB line protocol data to the configured TCP and/or UDP ad
 
 VictoriaMetrics performs the following transformations to the ingested InfluxDB data:
 
-* [db query arg](https://docs.influxdata.com/influxdb/v1.7/tools/api/#write-http-endpoint) is mapped into `db` label value
-  unless `db` tag exists in the InfluxDB line. The `db` label name can be overridden via `-influxDBLabel` command-line flag.
+* [db query arg](https://docs.influxdata.com/influxdb/v1.7/tools/api/#write-http-endpoint) is mapped into `db` 
+  [label](https://docs.victoriametrics.com/keyConcepts.html#labels) value unless `db` tag exists in the InfluxDB line. 
+  The `db` label name can be overridden via `-influxDBLabel` command-line flag. If more strict data isolation is required,
+  read more about multi-tenancy [here](https://docs.victoriametrics.com/keyConcepts.html#multi-tenancy).
 * Field names are mapped to time series names prefixed with `{measurement}{separator}` value, where `{separator}` equals to `_` by default. It can be changed with `-influxMeasurementFieldSeparator` command-line flag. See also `-influxSkipSingleField` command-line flag. If `{measurement}` is empty or if `-influxSkipMeasurement` command-line flag is set, then time series names correspond to field names.
 * Field values are mapped to time series values.
 * Tags are mapped to Prometheus labels as-is.
@@ -551,7 +604,8 @@ The `/api/v1/export` endpoint should return the following response:
 ```
 
 Note that InfluxDB line protocol expects [timestamps in *nanoseconds* by default](https://docs.influxdata.com/influxdb/v1.7/write_protocols/line_protocol_tutorial/#timestamp),
-while VictoriaMetrics stores them with *milliseconds* precision.
+while VictoriaMetrics stores them with *milliseconds* precision. It is allowed to ingest timestamps with seconds,
+microseconds or nanoseconds precision - VictoriaMetrics will automatically convert them to milliseconds.
 
 Extra labels may be added to all the written time series by passing `extra_label=name=value` query args.
 For example, `/write?extra_label=foo=bar` would add `{foo="bar"}` label to all the ingested metrics.
@@ -614,7 +668,6 @@ The `__graphite__` pseudo-label supports e.g. alternate regexp filters such as `
 
 VictoriaMetrics also supports Graphite query language - see [these docs](#graphite-render-api-usage).
 
-
 ## How to send data from OpenTSDB-compatible agents
 
 VictoriaMetrics supports [telnet put protocol](http://opentsdb.net/docs/build/html/api_telnet/put.html)
@@ -729,20 +782,45 @@ All the Prometheus querying API handlers can be prepended with `/prometheus` pre
 
 ### Prometheus querying API enhancements
 
-VictoriaMetrics accepts optional `extra_label=<label_name>=<label_value>` query arg, which can be used for enforcing additional label filters for queries. For example,
-`/api/v1/query_range?extra_label=user_id=123&extra_label=group_id=456&query=<query>` would automatically add `{user_id="123",group_id="456"}` label filters to the given `<query>`. This functionality can be used for limiting the scope of time series visible to the given tenant. It is expected that the `extra_label` query args are automatically set by auth proxy sitting in front of VictoriaMetrics. See [vmauth](https://docs.victoriametrics.com/vmauth.html) and [vmgateway](https://docs.victoriametrics.com/vmgateway.html) as examples of such proxies.
+VictoriaMetrics accepts optional `extra_label=<label_name>=<label_value>` query arg, which can be used
+for enforcing additional label filters for queries. For example, `/api/v1/query_range?extra_label=user_id=123&extra_label=group_id=456&query=<query>`
+would automatically add `{user_id="123",group_id="456"}` label filters to the given `<query>`.
+This functionality can be used for limiting the scope of time series visible to the given tenant.
+It is expected that the `extra_label` query args are automatically set by auth proxy sitting in front of VictoriaMetrics.
+See [vmauth](https://docs.victoriametrics.com/vmauth.html) and [vmgateway](https://docs.victoriametrics.com/vmgateway.html) as examples of such proxies.
 
-VictoriaMetrics accepts optional `extra_filters[]=series_selector` query arg, which can be used for enforcing arbitrary label filters for queries. For example,
-`/api/v1/query_range?extra_filters[]={env=~"prod|staging",user="xyz"}&query=<query>` would automatically add `{env=~"prod|staging",user="xyz"}` label filters to the given `<query>`. This functionality can be used for limiting the scope of time series visible to the given tenant. It is expected that the `extra_filters[]` query args are automatically set by auth proxy sitting in front of VictoriaMetrics. See [vmauth](https://docs.victoriametrics.com/vmauth.html) and [vmgateway](https://docs.victoriametrics.com/vmgateway.html) as examples of such proxies.
+VictoriaMetrics accepts optional `extra_filters[]=series_selector` query arg, which can be used for enforcing arbitrary label filters for queries.
+For example, `/api/v1/query_range?extra_filters[]={env=~"prod|staging",user="xyz"}&query=<query>` would automatically
+add `{env=~"prod|staging",user="xyz"}` label filters to the given `<query>`. This functionality can be used for limiting
+the scope of time series visible to the given tenant. It is expected that the `extra_filters[]` query args are automatically
+set by auth proxy sitting in front of VictoriaMetrics.
+See [vmauth](https://docs.victoriametrics.com/vmauth.html) and [vmgateway](https://docs.victoriametrics.com/vmgateway.html) as examples of such proxies.
 
 VictoriaMetrics accepts multiple formats for `time`, `start` and `end` query args - see [these docs](#timestamp-formats).
 
-VictoriaMetrics accepts `round_digits` query arg for `/api/v1/query` and `/api/v1/query_range` handlers. It can be used for rounding response values to the given number of digits after the decimal point. For example, `/api/v1/query?query=avg_over_time(temperature[1h])&round_digits=2` would round response values to up to two digits after the decimal point.
+VictoriaMetrics accepts `round_digits` query arg for [/api/v1/query](https://docs.victoriametrics.com/keyConcepts.html#instant-query)
+and [/api/v1/query_range](https://docs.victoriametrics.com/keyConcepts.html#range-query) handlers. It can be used for rounding response values
+to the given number of digits after the decimal point.
+For example, `/api/v1/query?query=avg_over_time(temperature[1h])&round_digits=2` would round response values to up to two digits after the decimal point.
 
-VictoriaMetrics accepts `limit` query arg for `/api/v1/labels` and `/api/v1/label/<labelName>/values` handlers for limiting the number of returned entries. For example, the query to `/api/v1/labels?limit=5` returns a sample of up to 5 unique labels, while ignoring the rest of labels. If the provided `limit` value exceeds the corresponding `-search.maxTagKeys` / `-search.maxTagValues` command-line flag values, then limits specified in the command-line flags are used.
+VictoriaMetrics accepts `limit` query arg for [/api/v1/labels](https://docs.victoriametrics.com/url-examples.html#apiv1labels)
+and [`/api/v1/label/<labelName>/values`](https://docs.victoriametrics.com/url-examples.html#apiv1labelvalues) handlers for limiting the number of returned entries.
+For example, the query to `/api/v1/labels?limit=5` returns a sample of up to 5 unique labels, while ignoring the rest of labels.
+If the provided `limit` value exceeds the corresponding `-search.maxTagKeys` / `-search.maxTagValues` command-line flag values,
+then limits specified in the command-line flags are used.
 
-By default, VictoriaMetrics returns time series for the last 5 minutes from `/api/v1/series`, `/api/v1/labels` and `/api/v1/label/<labelName>/values` while the Prometheus API defaults to all time.  Explicitly set `start` and `end` to select the desired time range.
-VictoriaMetrics accepts `limit` query arg for `/api/v1/series` handlers for limiting the number of returned entries. For example, the query to `/api/v1/series?limit=5` returns a sample of up to 5 series, while ignoring the rest. If the provided `limit` value exceeds the corresponding `-search.maxSeries` command-line flag values, then limits specified in the command-line flags are used.
+By default, VictoriaMetrics returns time series for the last day starting at 00:00 UTC
+from [/api/v1/series](https://docs.victoriametrics.com/url-examples.html#apiv1series),
+[/api/v1/labels](https://docs.victoriametrics.com/url-examples.html#apiv1labels) and
+[`/api/v1/label/<labelName>/values`](https://docs.victoriametrics.com/url-examples.html#apiv1labelvalues),
+while the Prometheus API defaults to all time.  Explicitly set `start` and `end` to select the desired time range.
+VictoriaMetrics rounds the specified `start..end` time range to day granularity because of performance optimization concerns.
+If you need the exact set of label names and label values on the given time range, then send queries
+to [/api/v1/query](https://docs.victoriametrics.com/keyConcepts.html#instant-query) or to [/api/v1/query_range](https://docs.victoriametrics.com/keyConcepts.html#range-query).
+
+VictoriaMetrics accepts `limit` query arg at [/api/v1/series](https://docs.victoriametrics.com/url-examples.html#apiv1series)
+for limiting the number of returned entries. For example, the query to `/api/v1/series?limit=5` returns a sample of up to 5 series, while ignoring the rest of series.
+If the provided `limit` value exceeds the corresponding `-search.maxSeries` command-line flag values, then limits specified in the command-line flags are used.
 
 Additionally, VictoriaMetrics provides the following handlers:
 
@@ -767,9 +845,12 @@ in [query APIs](https://docs.victoriametrics.com/#prometheus-querying-api-usage)
 in [export APIs](https://docs.victoriametrics.com/#how-to-export-time-series).
 
 - Unix timestamps in seconds with optional milliseconds after the point. For example, `1562529662.678`.
-- [RFC3339](https://www.ietf.org/rfc/rfc3339.txt). For example, '2022-03-29T01:02:03Z`.
-- Partial RFC3339. Examples: `2022`, `2022-03`, `2022-03-29`, `2022-03-29T01`, `2022-03-29T01:02`.
-- Relative duration comparing to the current time. For example, `1h5m` means `one hour and five minutes ago`.
+- Unix timestamps in milliseconds. For example, `1562529662678`.
+- [RFC3339](https://www.ietf.org/rfc/rfc3339.txt). For example, `2022-03-29T01:02:03Z` or `2022-03-29T01:02:03+02:30`.
+- Partial RFC3339. Examples: `2022`, `2022-03`, `2022-03-29`, `2022-03-29T01`, `2022-03-29T01:02`, `2022-03-29T01:02:03`.
+  The partial RFC3339 time is in UTC timezone by default. It is possible to specify timezone there by adding `+hh:mm` or `-hh:mm` suffix to partial time.
+  For example, `2022-03-01+06:30` is `2022-03-01` at `06:30` timezone.
+- Relative duration comparing to the current time. For example, `1h5m`, `-1h5m` or `now-1h5m` means `one hour and five minutes ago`, while `now` means `now`.
 
 
 ## Graphite API usage
@@ -791,10 +872,10 @@ VictoriaMetrics supports `__graphite__` pseudo-label for filtering time series w
 
 ### Graphite Render API usage
 
-[VictoriaMetrics Enterprise](https://docs.victoriametrics.com/enterprise.html) supports [Graphite Render API](https://graphite.readthedocs.io/en/stable/render_api.html) subset
+VictoriaMetrics supports [Graphite Render API](https://graphite.readthedocs.io/en/stable/render_api.html) subset
 at `/render` endpoint, which is used by [Graphite datasource in Grafana](https://grafana.com/docs/grafana/latest/datasources/graphite/).
-When configuring Graphite datasource in Grafana, the `Storage-Step` http request header must be set to a step between Graphite data points stored in VictoriaMetrics. For example, `Storage-Step: 10s` would mean 10 seconds distance between Graphite datapoints stored in VictoriaMetrics.
-Enterprise binaries can be downloaded and evaluated for free from [the releases page](https://github.com/VictoriaMetrics/VictoriaMetrics/releases).
+When configuring Graphite datasource in Grafana, the `Storage-Step` http request header must be set to a step between Graphite data points
+stored in VictoriaMetrics. For example, `Storage-Step: 10s` would mean 10 seconds distance between Graphite datapoints stored in VictoriaMetrics.
 
 ### Graphite Metrics API usage
 
@@ -806,7 +887,7 @@ VictoriaMetrics supports the following handlers from [Graphite Metrics API](http
 
 VictoriaMetrics accepts the following additional query args at `/metrics/find` and `/metrics/expand`:
 
-* `label` - for selecting arbitrary label values. By default `label=__name__`, i.e. metric names are selected.
+* `label` - for selecting arbitrary label values. By default, `label=__name__`, i.e. metric names are selected.
 * `delimiter` - for using different delimiters in metric name hierarchy. For example, `/metrics/find?delimiter=_&query=node_*` would return all the metric name prefixes
     that start with `node_`. By default `delimiter=.`.
 
@@ -833,13 +914,13 @@ to your needs or when testing bugfixes.
 ### Development build
 
 1. [Install Go](https://golang.org/doc/install). The minimum supported version is Go 1.19.
-2. Run `make victoria-metrics` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make victoria-metrics` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `victoria-metrics` binary and puts it into the `bin` folder.
 
 ### Production build
 
 1. [Install docker](https://docs.docker.com/install/).
-2. Run `make victoria-metrics-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make victoria-metrics-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `victoria-metrics-prod` binary and puts it into the `bin` folder.
 
 ### ARM build
@@ -849,13 +930,13 @@ ARM build may run on Raspberry Pi or on [energy-efficient ARM servers](https://b
 ### Development ARM build
 
 1. [Install Go](https://golang.org/doc/install). The minimum supported version is Go 1.19.
-2. Run `make victoria-metrics-linux-arm` or `make victoria-metrics-linux-arm64` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make victoria-metrics-linux-arm` or `make victoria-metrics-linux-arm64` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `victoria-metrics-linux-arm` or `victoria-metrics-linux-arm64` binary respectively and puts it into the `bin` folder.
 
 ### Production ARM build
 
 1. [Install docker](https://docs.docker.com/install/).
-2. Run `make victoria-metrics-linux-arm-prod` or `make victoria-metrics-linux-arm64-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make victoria-metrics-linux-arm-prod` or `make victoria-metrics-linux-arm64-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `victoria-metrics-linux-arm-prod` or `victoria-metrics-linux-arm64-prod` binary respectively and puts it into the `bin` folder.
 
 ### Pure Go build (CGO_ENABLED=0)
@@ -863,7 +944,7 @@ ARM build may run on Raspberry Pi or on [energy-efficient ARM servers](https://b
 `Pure Go` mode builds only Go code without [cgo](https://golang.org/cmd/cgo/) dependencies.
 
 1. [Install Go](https://golang.org/doc/install). The minimum supported version is Go 1.19.
-2. Run `make victoria-metrics-pure` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make victoria-metrics-pure` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `victoria-metrics-pure` binary and puts it into the `bin` folder.
 
 ### Building docker images
@@ -916,9 +997,9 @@ Navigate to `http://<victoriametrics-addr>:8428/snapshot/delete_all` in order to
 Steps for restoring from a snapshot:
 
 1. Stop VictoriaMetrics with `kill -INT`.
-2. Restore snapshot contents from backup with [vmrestore](https://docs.victoriametrics.com/vmrestore.html)
+1. Restore snapshot contents from backup with [vmrestore](https://docs.victoriametrics.com/vmrestore.html)
    to the directory pointed by `-storageDataPath`.
-3. Start VictoriaMetrics.
+1. Start VictoriaMetrics.
 
 ## How to delete time series
 
@@ -932,7 +1013,7 @@ Note that background merges may never occur for data from previous months, so st
 In this case [forced merge](#forced-merge) may help freeing up storage space.
 
 It is recommended verifying which metrics will be deleted with the call to `http://<victoria-metrics-addr>:8428/api/v1/series?match[]=<timeseries_selector_for_delete>`
-before actually deleting the metrics.  By default this query will only scan series in the past 5 minutes, so you may need to
+before actually deleting the metrics. By default, this query will only scan series in the past 5 minutes, so you may need to
 adjust `start` and `end` to a suitable range to achieve match hits.
 
 The `/api/v1/admin/tsdb/delete_series` handler may be protected with `authKey` if `-deleteAuthKey` command-line flag is set.
@@ -983,7 +1064,7 @@ VictoriaMetrics provides the following handlers for exporting data:
 Send a request to `http://<victoriametrics-addr>:8428/api/v1/export?match[]=<timeseries_selector_for_export>`,
 where `<timeseries_selector_for_export>` may contain any [time series selector](https://prometheus.io/docs/prometheus/latest/querying/basics/#time-series-selectors)
 for metrics to export. Use `{__name__!=""}` selector for fetching all the time series.
-The response would contain all the data for the selected time series in [JSON streaming format](https://en.wikipedia.org/wiki/JSON_streaming#Line-delimited_JSON).
+The response would contain all the data for the selected time series in [JSON streaming format](http://ndjson.org/).
 Each JSON line contains samples for a single time series. An example output:
 
 ```json
@@ -997,7 +1078,7 @@ See [allowed formats](#timestamp-formats) for these args.
 For example:
 ```console
 curl http://<victoriametrics-addr>:8428/api/v1/export -d 'match[]=<timeseries_selector_for_export>' -d 'start=1654543486' -d 'end=1654543486'
-curl http://<victoriametrics-addr>:8428/api/v1/export -d 'match[]=<timeseries_selector_for_export>' -d 'start=2022-06-06T19:25:48+00:00' -d 'end=2022-06-06T19:29:07+00:00'
+curl http://<victoriametrics-addr>:8428/api/v1/export -d 'match[]=<timeseries_selector_for_export>' -d 'start=2022-06-06T19:25:48' -d 'end=2022-06-06T19:29:07'
 ```
 
 Optional `max_rows_per_line` arg may be added to the request for limiting the maximum number of rows exported per each JSON line.
@@ -1046,7 +1127,7 @@ See [allowed formats](#timestamp-formats) for these args.
 For example:
 ```console
 curl http://<victoriametrics-addr>:8428/api/v1/export/csv -d 'format=<format>' -d 'match[]=<timeseries_selector_for_export>' -d 'start=1654543486' -d 'end=1654543486'
-curl http://<victoriametrics-addr>:8428/api/v1/export/csv -d 'format=<format>' -d 'match[]=<timeseries_selector_for_export>' -d 'start=2022-06-06T19:25:48+00:00' -d 'end=2022-06-06T19:29:07+00:00'
+curl http://<victoriametrics-addr>:8428/api/v1/export/csv -d 'format=<format>' -d 'match[]=<timeseries_selector_for_export>' -d 'start=2022-06-06T19:25:48' -d 'end=2022-06-06T19:29:07'
 ```
 
 The exported CSV data can be imported to VictoriaMetrics via [/api/v1/import/csv](#how-to-import-csv-data).
@@ -1074,7 +1155,7 @@ See [allowed formats](#timestamp-formats) for these args.
 For example:
 ```console
 curl http://<victoriametrics-addr>:8428/api/v1/export/native -d 'match[]=<timeseries_selector_for_export>' -d 'start=1654543486' -d 'end=1654543486'
-curl http://<victoriametrics-addr>:8428/api/v1/export/native -d 'match[]=<timeseries_selector_for_export>' -d 'start=2022-06-06T19:25:48+00:00' -d 'end=2022-06-06T19:29:07+00:00'
+curl http://<victoriametrics-addr>:8428/api/v1/export/native -d 'match[]=<timeseries_selector_for_export>' -d 'start=2022-06-06T19:25:48' -d 'end=2022-06-06T19:29:07'
 ```
 
 The exported data can be imported to VictoriaMetrics via [/api/v1/import/native](#how-to-import-data-in-native-format).
@@ -1093,6 +1174,7 @@ Additionally, VictoriaMetrics can accept metrics via the following popular data
 * DataDog `submit metrics` API. See [these docs](#how-to-send-data-from-datadog-agent) for details.
 * InfluxDB line protocol. See [these docs](#how-to-send-data-from-influxdb-compatible-agents-such-as-telegraf) for details.
 * Graphite plaintext protocol. See [these docs](#how-to-send-data-from-graphite-compatible-agents-such-as-statsd) for details.
+* OpenTelemetry http API. See [these docs](#sending-data-via-opentelemetry) for details.
 * OpenTSDB telnet put protocol. See [these docs](#sending-data-via-telnet-put-protocol) for details.
 * OpenTSDB http `/api/put` protocol. See [these docs](#sending-opentsdb-data-via-http-apiput-requests) for details.
 * `/api/v1/import` for importing data obtained from [/api/v1/export](#how-to-export-data-in-json-line-format).
@@ -1103,6 +1185,13 @@ Additionally, VictoriaMetrics can accept metrics via the following popular data
 * `/api/v1/import/prometheus` for importing data in Prometheus exposition format and in [Pushgateway format](https://github.com/prometheus/pushgateway#url).
   See [these docs](#how-to-import-data-in-prometheus-exposition-format) for details.
 
+Please note, most of the ingestion APIs (except [Prometheus remote_write API](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#remote_write))
+are optimized for performance and processes data in a streaming fashion.
+It means that client can transfer unlimited amount of data through the open connection. Because of this, import APIs
+may not return parsing errors to the client, as it is expected for data stream to be not interrupted. 
+Instead, look for parsing errors on the server side (VictoriaMetrics single-node or vminsert) or
+check for changes in `vm_rows_invalid_total` (exported by server side) metric.
+
 ### How to import data in JSON line format
 
 Example for importing data obtained via [/api/v1/export](#how-to-export-data-in-json-line-format):
@@ -1269,6 +1358,13 @@ Note that it could be required to flush response cache after importing historica
 
 VictoriaMetrics also may scrape Prometheus targets - see [these docs](#how-to-scrape-prometheus-exporters-such-as-node-exporter).
 
+## Sending data via OpenTelemetry
+
+VictoriaMetrics supports data ingestion via [OpenTelemetry protocol for metrics](https://github.com/open-telemetry/opentelemetry-specification/blob/ffddc289462dfe0c2041e3ca42a7b1df805706de/specification/metrics/data-model.md) at `/opentemetry/api/v1/push` path.
+
+VictoriaMetrics expects `protobuf`-encoded requests at `/opentelemetry/api/v1/push`.
+Set HTTP request header `Content-Encoding: gzip` when sending gzip-compressed data to `/opentelemetry/api/v1/push`.
+
 ## Relabeling
 
 VictoriaMetrics supports Prometheus-compatible relabeling for all the ingested metrics if `-relabelConfig` command-line flag points
@@ -1298,7 +1394,8 @@ Example contents for `-relabelConfig` file:
 VictoriaMetrics provides additional relabeling features such as Graphite-style relabeling.
 See [these docs](https://docs.victoriametrics.com/vmagent.html#relabeling) for more details.
 
-The relabeling can be debugged at `http://victoriametrics:8428/metric-relabel-debug` page.
+The relabeling can be debugged at `http://victoriametrics:8428/metric-relabel-debug` page
+or at our [public playground](https://play.victoriametrics.com/select/accounting/1/6a716b0f-38bc-4856-90ce-448fd713e3fe/prometheus/graph/#/relabeling).
 See [these docs](https://docs.victoriametrics.com/vmagent.html#relabel-debug) for more details.
 
 
@@ -1313,7 +1410,7 @@ See [allowed formats](#timestamp-formats) for these args.
 For example:
 ```console
 curl http://<victoriametrics-addr>:8428/federate -d 'match[]=<timeseries_selector_for_export>' -d 'start=1654543486' -d 'end=1654543486'
-curl http://<victoriametrics-addr>:8428/federate -d 'match[]=<timeseries_selector_for_export>' -d 'start=2022-06-06T19:25:48+00:00' -d 'end=2022-06-06T19:29:07+00:00'
+curl http://<victoriametrics-addr>:8428/federate -d 'match[]=<timeseries_selector_for_export>' -d 'start=2022-06-06T19:25:48' -d 'end=2022-06-06T19:29:07'
 ```
 By default, the last point on the interval `[now - max_lookback ... now]` is scraped for each time series. The default value for `max_lookback` is `5m` (5 minutes), but it can be overridden with `max_lookback` query arg.
 For instance, `/federate?match[]=up&max_lookback=1h` would return last points on the `[now - 1h ... now]` interval. This may be useful for time series federation
@@ -1345,7 +1442,7 @@ See also [resource usage limits docs](#resource-usage-limits).
 
 ## Resource usage limits
 
-By default VictoriaMetrics is tuned for an optimal resource usage under typical workloads. Some workloads may need fine-grained resource usage limits. In these cases the following command-line flags may be useful:
+By default, VictoriaMetrics is tuned for an optimal resource usage under typical workloads. Some workloads may need fine-grained resource usage limits. In these cases the following command-line flags may be useful:
 
 - `-memory.allowedPercent` and `-memory.allowedBytes` limit the amounts of memory, which may be used for various internal caches at VictoriaMetrics. Note that VictoriaMetrics may use more memory, since these flags don't limit additional memory, which may be needed on a per-query basis.
 - `-search.maxMemoryPerQuery` limits the amounts of memory, which can be used for processing a single query. Queries, which need more memory, are rejected. Heavy queries, which select big number of time series, may exceed the per-query memory limit by a small percent. The total memory limit for concurrently executed queries can be estimated as `-search.maxMemoryPerQuery` multiplied by `-search.maxConcurrentRequests`.
@@ -1356,6 +1453,7 @@ By default VictoriaMetrics is tuned for an optimal resource usage under typical
 - `-search.maxSamplesPerQuery` limits the number of raw samples a single query can process. This allows limiting CPU usage for heavy queries.
 - `-search.maxPointsPerTimeseries` limits the number of calculated points, which can be returned per each matching time series from [range query](https://docs.victoriametrics.com/keyConcepts.html#range-query).
 - `-search.maxPointsSubqueryPerTimeseries` limits the number of calculated points, which can be generated per each matching time series during [subquery](https://docs.victoriametrics.com/MetricsQL.html#subqueries) evaluation.
+- `-search.maxSeriesPerAggrFunc` limits the number of time series, which can be generated by [MetricsQL aggregate functions](https://docs.victoriametrics.com/MetricsQL.html#aggregate-functions) in a single query.
 - `-search.maxSeries` limits the number of time series, which may be returned from [/api/v1/series](https://prometheus.io/docs/prometheus/latest/querying/api/#finding-series-by-label-matchers). This endpoint is used mostly by Grafana for auto-completion of metric names, label names and label values. Queries to this endpoint may take big amounts of CPU time and memory when the database contains big number of unique time series because of [high churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate). In this case it might be useful to set the `-search.maxSeries` to quite low value in order limit CPU and memory usage.
 - `-search.maxTagKeys` limits the number of items, which may be returned from [/api/v1/labels](https://prometheus.io/docs/prometheus/latest/querying/api/#getting-label-names). This endpoint is used mostly by Grafana for auto-completion of label names. Queries to this endpoint may take big amounts of CPU time and memory when the database contains big number of unique time series because of [high churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate). In this case it might be useful to set the `-search.maxTagKeys` to quite low value in order to limit CPU and memory usage.
 - `-search.maxTagValues` limits the number of items, which may be returned from [/api/v1/label/.../values](https://prometheus.io/docs/prometheus/latest/querying/api/#querying-label-values). This endpoint is used mostly by Grafana for auto-completion of label values. Queries to this endpoint may take big amounts of CPU time and memory when the database contains big number of unique time series because of [high churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate). In this case it might be useful to set the `-search.maxTagValues` to quite low value in order to limit CPU and memory usage.
@@ -1406,22 +1504,37 @@ with the enabled de-duplication. See [this section](#deduplication) for details.
 
 ## Deduplication
 
-VictoriaMetrics leaves a single raw sample with the biggest timestamp per each `-dedup.minScrapeInterval` discrete interval
-if `-dedup.minScrapeInterval` is set to positive duration. For example, `-dedup.minScrapeInterval=60s` would leave a single
-raw sample with the biggest timestamp per each discrete 60s interval.
+VictoriaMetrics leaves a single [raw sample](https://docs.victoriametrics.com/keyConcepts.html#raw-samples)
+with the biggest [timestamp](https://en.wikipedia.org/wiki/Unix_time) for each [time series](https://docs.victoriametrics.com/keyConcepts.html#time-series)
+per each `-dedup.minScrapeInterval` discrete interval if `-dedup.minScrapeInterval` is set to positive duration. 
+For example, `-dedup.minScrapeInterval=60s` would leave a single raw sample with the biggest timestamp per each discrete
+`60s` interval.
 This aligns with the [staleness rules in Prometheus](https://prometheus.io/docs/prometheus/latest/querying/basics/#staleness).
 
-If multiple raw samples have the same biggest timestamp on the given `-dedup.minScrapeInterval` discrete interval, then the sample with the biggest value is left.
+If multiple raw samples have **the same timestamp** on the given `-dedup.minScrapeInterval` discrete interval, 
+then the sample with **the biggest value** is kept.
 
-The `-dedup.minScrapeInterval=D` is equivalent to `-downsampling.period=0s:D` if [downsampling](#downsampling) is enabled. So it is safe to use deduplication and downsampling simultaneously.
+Please note, [labels](https://docs.victoriametrics.com/keyConcepts.html#labels) of raw samples should be identical
+in order to be deduplicated. For example, this is why [HA pair of vmagents](https://docs.victoriametrics.com/vmagent.html#high-availability)
+needs to be identically configured. 
 
-The recommended value for `-dedup.minScrapeInterval` must equal to `scrape_interval` config from Prometheus configs. It is recommended to have a single `scrape_interval` across all the scrape targets. See [this article](https://www.robustperception.io/keep-it-simple-scrape_interval-id) for details.
+The `-dedup.minScrapeInterval=D` is equivalent to `-downsampling.period=0s:D` if [downsampling](#downsampling) is enabled.
+So it is safe to use deduplication and downsampling simultaneously.
 
-The de-duplication reduces disk space usage if multiple identically configured [vmagent](https://docs.victoriametrics.com/vmagent.html) or Prometheus instances in HA pair
-write data to the same VictoriaMetrics instance. These vmagent or Prometheus instances must have identical
-`external_labels` section in their configs, so they write data to the same time series. See also [how to set up multiple vmagent instances for scraping the same targets](https://docs.victoriametrics.com/vmagent.html#scraping-big-number-of-targets).
+The recommended value for `-dedup.minScrapeInterval` must equal to `scrape_interval` config from Prometheus configs. 
+It is recommended to have a single `scrape_interval` across all the scrape targets. 
+See [this article](https://www.robustperception.io/keep-it-simple-scrape_interval-id) for details.
 
-It is recommended passing different `-promscrape.cluster.name` values to HA pairs of `vmagent` instances, so the de-duplication consistently leaves samples for one `vmagent` instance and removes duplicate samples from other `vmagent` instances. See [these docs](https://docs.victoriametrics.com/vmagent.html#high-availability) for details.
+The de-duplication reduces disk space usage if multiple **identically configured** [vmagent](https://docs.victoriametrics.com/vmagent.html)
+or Prometheus instances in HA pair write data to the same VictoriaMetrics instance. 
+These vmagent or Prometheus instances must have **identical** `external_labels` section in their configs, 
+so they write data to the same time series. 
+See also [how to set up multiple vmagent instances for scraping the same targets](https://docs.victoriametrics.com/vmagent.html#scraping-big-number-of-targets).
+
+It is recommended passing different `-promscrape.cluster.name` values to each distinct HA pair of `vmagent` instances, 
+so the de-duplication consistently leaves samples for one `vmagent` instance and removes duplicate samples 
+from other `vmagent` instances. 
+See [these docs](https://docs.victoriametrics.com/vmagent.html#high-availability) for details.
 
 ## Storage
 
@@ -1433,12 +1546,14 @@ can be configured with the `-inmemoryDataFlushInterval` command-line flag (note
 In-memory parts are persisted to disk into `part` directories under the `<-storageDataPath>/data/small/YYYY_MM/` folder,
 where `YYYY_MM` is the month partition for the stored data. For example, `2022_11` is the partition for `parts`
 with [raw samples](https://docs.victoriametrics.com/keyConcepts.html#raw-samples) from `November 2022`.
+Each partition directory contains `parts.json` file with the actual list of parts in the partition.
 
-The `part` directory has the following name pattern: `rowsCount_blocksCount_minTimestamp_maxTimestamp`, where:
+Every `part` directory contains `metadata.json` file with the following fields:
 
-- `rowsCount` - the number of [raw samples](https://docs.victoriametrics.com/keyConcepts.html#raw-samples) stored in the part
-- `blocksCount` - the number of blocks stored in the part (see details about blocks below)
-- `minTimestamp` and `maxTimestamp` - minimum and maximum timestamps across raw samples stored in the part
+- `RowsCount` - the number of [raw samples](https://docs.victoriametrics.com/keyConcepts.html#raw-samples) stored in the part
+- `BlocksCount` - the number of blocks stored in the part (see details about blocks below)
+- `MinTimestamp` and `MaxTimestamp` - minimum and maximum timestamps across raw samples stored in the part
+- `MinDedupInterval` - the [deduplication interval](#deduplication) applied to the given part.
 
 Each `part` consists of `blocks` sorted by internal time series id (aka `TSID`).
 Each `block` contains up to 8K [raw samples](https://docs.victoriametrics.com/keyConcepts.html#raw-samples),
@@ -1460,15 +1575,20 @@ for fast block lookups, which belong to the given `TSID` and cover the given tim
   and [freeing up disk space for the deleted time series](#how-to-delete-time-series) are performed during the merge
 
 Newly added `parts` either successfully appear in the storage or fail to appear.
-The newly added `parts` are being created in a temporary directory under `<-storageDataPath>/data/{small,big}/YYYY_MM/tmp` folder.
-When the newly added `part` is fully written and [fsynced](https://man7.org/linux/man-pages/man2/fsync.2.html)
-to a temporary directory, then it is atomically moved to the storage directory.
-Thanks to this alogrithm, storage never contains partially created parts, even if hardware power off
-occurrs in the middle of writing the `part` to disk - such incompletely written `parts`
+The newly added `part` is atomically registered in the `parts.json` file under the corresponding partition
+after it is fully written and [fsynced](https://man7.org/linux/man-pages/man2/fsync.2.html) to the storage.
+Thanks to this algorithm, storage never contains partially created parts, even if hardware power off
+occurs in the middle of writing the `part` to disk - such incompletely written `parts`
 are automatically deleted on the next VictoriaMetrics start.
 
 The same applies to merge process — `parts` are either fully merged into a new `part` or fail to merge,
-leaving the source `parts` untouched.
+leaving the source `parts` untouched. However, due to hardware issues data on disk may be corrupted regardless of
+VictoriaMetrics process. VictoriaMetrics can detect corruption during decompressing, decoding or sanity checking
+of the data blocks. But **it cannot fix the corrupted data**. Data parts that fail to load on startup need to be deleted
+or restored from backups. This is why it is recommended performing
+[regular backups](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#backups).
+
+VictoriaMetrics doesn't use checksums for stored data blocks. See why [here](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3011).
 
 VictoriaMetrics doesn't merge parts if their summary size exceeds free disk space.
 This prevents from potential out of disk space errors during merge.
@@ -1487,20 +1607,22 @@ See also [how to work with snapshots](#how-to-work-with-snapshots).
 
 ## Retention
 
-Retention is configured with the `-retentionPeriod` command-line flag, which takes a number followed by a time unit character - `h(ours)`, `d(ays)`, `w(eeks)`, `y(ears)`. If the time unit is not specified, a month is assumed. For instance, `-retentionPeriod=3` means that the data will be stored for 3 months and then deleted. The default retention period is one month.
+Retention is configured with the `-retentionPeriod` command-line flag, which takes a number followed by a time unit 
+character - `h(ours)`, `d(ays)`, `w(eeks)`, `y(ears)`. If the time unit is not specified, a month is assumed. 
+For instance, `-retentionPeriod=3` means that the data will be stored for 3 months and then deleted. 
+The default retention period is one month. The **minimum retention** period is 24h or 1d.
 
 Data is split in per-month partitions inside `<-storageDataPath>/data/{small,big}` folders.
-Data partitions outside the configured retention are deleted on the first day of the new month.
-Each partition consists of one or more data parts with the following name pattern `rowsCount_blocksCount_minTimestamp_maxTimestamp`.
-Data parts outside of the configured retention are eventually deleted during
-[background merge](https://medium.com/@valyala/how-victoriametrics-makes-instant-snapshots-for-multi-terabyte-time-series-data-e1f3fb0e0282).
+**Data partitions** outside the configured retention are deleted **on the first day of the new month**.
+Each partition consists of one or more **data parts**. Data parts outside the configured retention 
+are **eventually deleted** during [background merge](https://medium.com/@valyala/how-victoriametrics-makes-instant-snapshots-for-multi-terabyte-time-series-data-e1f3fb0e0282).
+The time range covered by data part is **not limited by retention period unit**. One data part can cover hours or days of 
+data. Hence, a data part can be deleted only **when fully outside the configured retention**.
+See more about partitions and parts [here](#storage).
 
 The maximum disk space usage for a given `-retentionPeriod` is going to be (`-retentionPeriod` + 1) months.
 For example, if `-retentionPeriod` is set to 1, data for January is deleted on March 1st.
 
-Please note, the time range covered by data part is not limited by retention period unit. Hence, data part may contain data
-for multiple days and will be deleted only when fully outside of the configured retention.
-
 It is safe to extend `-retentionPeriod` on existing data. If `-retentionPeriod` is set to a lower
 value than before, then data outside the configured period will be eventually deleted.
 
@@ -1543,7 +1665,7 @@ For example, the following config sets 3 days retention for time series with `te
 
 Important notes:
 
-- The data outside of the configured retention isn't deleted instantly - it is deleted eventually during [background merges](https://docs.victoriametrics.com/#storage).
+- The data outside the configured retention isn't deleted instantly - it is deleted eventually during [background merges](https://docs.victoriametrics.com/#storage).
 - The `-retentionFilter` doesn't remove old data from `indexdb` (aka inverted index) until the configured [-retentionPeriod](#retention).
   So the `indexdb` size can grow big under [high churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate)
   even for small retentions configured via `-retentionFilter`.
@@ -1563,7 +1685,12 @@ Retention filters can be evaluated for free by downloading and using enterprise
 
 * `-downsampling.period=30d:5m,180d:1h` instructs VictoriaMetrics to deduplicate samples older than 30 days with 5 minutes interval and to deduplicate samples older than 180 days with 1 hour interval.
 
-Downsampling is applied independently per each time series. It can reduce disk space usage and improve query performance if it is applied to time series with big number of samples per each series. The downsampling doesn't improve query performance if the database contains big number of time series with small number of samples per each series (aka [high churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate)), since downsampling doesn't reduce the number of time series. So the majority of time is spent on searching for the matching time series. It is possible to use recording rules in [vmalert](https://docs.victoriametrics.com/vmalert.html) in order to reduce the number of time series. See [these docs](https://docs.victoriametrics.com/vmalert.html#downsampling-and-aggregation-via-vmalert).
+Downsampling is applied independently per each time series. It can reduce disk space usage and improve query performance if it is applied to time series with big number of samples per each series. The downsampling doesn't improve query performance if the database contains big number of time series with small number of samples per each series (aka [high churn rate](https://docs.victoriametrics.com/FAQ.html#what-is-high-churn-rate)), since downsampling doesn't reduce the number of time series. So the majority of time is spent on searching for the matching time series. 
+It is possible to use [stream aggregation](https://docs.victoriametrics.com/stream-aggregation.html) in vmagent or recording rules in [vmalert](https://docs.victoriametrics.com/vmalert.html) in order to [reduce the number of time series](https://docs.victoriametrics.com/vmalert.html#downsampling-and-aggregation-via-vmalert).
+
+Downsampling happens during [background merges](https://docs.victoriametrics.com/#storage) 
+and can't be performed if there is not enough of free disk space or if vmstorage 
+is in [read-only mode](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#readonly-mode).
 
 The downsampling can be evaluated for free by downloading and using enterprise binaries from [the releases page](https://github.com/VictoriaMetrics/VictoriaMetrics/releases).
 
@@ -1674,6 +1801,11 @@ VictoriaMetrics returns TSDB stats at `/api/v1/status/tsdb` page in the way simi
 * `match[]=SELECTOR` where `SELECTOR` is an arbitrary [time series selector](https://prometheus.io/docs/prometheus/latest/querying/basics/#time-series-selectors) for series to take into account during stats calculation. By default all the series are taken into account.
 * `extra_label=LABEL=VALUE`. See [these docs](#prometheus-querying-api-enhancements) for more details.
 
+In [cluster version of VictoriaMetrics](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html) each vmstorage tracks the stored time series individually.
+vmselect requests stats via [/api/v1/status/tsdb](#tsdb-stats) API from each vmstorage node and merges the results by summing per-series stats.
+This may lead to inflated values when samples for the same time series are spread across multiple vmstorage nodes
+due to [replication](#replication) or [rerouting](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html?highlight=re-routes#cluster-availability).
+
 VictoriaMetrics provides an UI on top of `/api/v1/status/tsdb` - see [cardinality explorer docs](#cardinality-explorer).
 
 ## Query tracing
@@ -1885,7 +2017,14 @@ are added to all the metrics before sending them to the remote storage:
 
 ## Cache removal
 
-VictoriaMetrics uses various internal caches. These caches are stored to `<-storageDataPath>/cache` directory during graceful shutdown (e.g. when VictoriaMetrics is stopped by sending `SIGINT` signal). The caches are read on the next VictoriaMetrics startup. Sometimes it is needed to remove such caches on the next startup. This can be performed by placing `reset_cache_on_startup` file inside the `<-storageDataPath>/cache` directory before the restart of VictoriaMetrics. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1447) for details.
+VictoriaMetrics uses various internal caches. These caches are stored to `<-storageDataPath>/cache` directory during graceful shutdown
+(e.g. when VictoriaMetrics is stopped by sending `SIGINT` signal). The caches are read on the next VictoriaMetrics startup.
+Sometimes it is needed to remove such caches on the next startup. This can be done in the following ways:
+
+- By manually removing the `<-storageDataPath>/cache` directory when VictoriaMetrics is stopped.
+- By placing `reset_cache_on_startup` file inside the `<-storageDataPath>/cache` directory before the restart of VictoriaMetrics.
+  In this case VictoriaMetrics will automatically remove all the caches on the next start.
+  See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1447) for details.
 
 ## Cache tuning
 
@@ -1920,16 +2059,16 @@ The simplest way to migrate data from one single-node (source) to another (desti
 to another do the following:
 
 1. Stop the VictoriaMetrics (source) with `kill -INT`;
-2. Copy (via [rsync](https://en.wikipedia.org/wiki/Rsync) or any other tool) the entire folder specified
+1. Copy (via [rsync](https://en.wikipedia.org/wiki/Rsync) or any other tool) the entire folder specified
 via `-storageDataPath` from the source node to the empty folder at the destination node.
-3. Once copy is done, stop the VictoriaMetrics (destination) with `kill -INT` and verify that
+1. Once copy is done, stop the VictoriaMetrics (destination) with `kill -INT` and verify that
 its `-storageDataPath` points to the copied folder from p.2;
-4. Start the VictoriaMetrics (destination). The copied data should be now available.
+1. Start the VictoriaMetrics (destination). The copied data should be now available.
 
 Things to consider when copying data:
 
 1. Data formats between single-node and vmstorage node aren't compatible and can't be copied.
-2. Copying data folder means complete replacement of the previous data on destination VictoriaMetrics.
+1. Copying data folder means complete replacement of the previous data on destination VictoriaMetrics.
 
 For more complex scenarios like single-to-cluster, cluster-to-single, re-sharding or migrating only a fraction
 of data - see [vmctl. Migrating data from VictoriaMetrics](https://docs.victoriametrics.com/vmctl.html#migrating-data-from-victoriametrics).
@@ -1955,8 +2094,7 @@ It is recommended disabling query cache with `-search.disableCache` command-line
 historical data with timestamps from the past, since the cache assumes that the data is written with
 the current timestamps. Query cache can be enabled after the backfilling is complete.
 
-An alternative solution is to query `/internal/resetRollupResultCache` url after backfilling is complete. This will reset
-the query cache, which could contain incomplete data cached during the backfilling.
+An alternative solution is to query [/internal/resetRollupResultCache](https://docs.victoriametrics.com/url-examples.html#internalresetRollupResultCache) handler after the backfilling is complete. This will reset the query cache, which could contain incomplete data cached during the backfilling.
 
 Yet another solution is to increase `-search.cacheTimestampOffset` flag value in order to disable caching
 for data with timestamps close to the current time. Single-node VictoriaMetrics automatically resets response
@@ -1990,9 +2128,9 @@ Enterprise binaries can be downloaded and evaluated for free from [the releases
 A single-node VictoriaMetrics is capable of proxying requests to [vmalert](https://docs.victoriametrics.com/vmalert.html)
 when `-vmalert.proxyURL` flag is set. Use this feature for the following cases:
 * for proxying requests from [Grafana Alerting UI](https://grafana.com/docs/grafana/latest/alerting/);
-* for accessing vmalert's UI through single-node VictoriaMetrics Web interface.
+* for accessing vmalerts UI through single-node VictoriaMetrics Web interface.
 
-For accessing vmalert's UI through single-node VictoriaMetrics configure `-vmalert.proxyURL` flag and visit
+For accessing vmalerts UI through single-node VictoriaMetrics configure `-vmalert.proxyURL` flag and visit
 `http://<victoriametrics-addr>:8428/vmalert/` link.
 
 ## Benchmarks
@@ -2037,17 +2175,10 @@ It is safe sharing the collected profiles from security point of view, since the
 
 ## Integrations
 
-* [Helm charts for single-node and cluster versions of VictoriaMetrics](https://github.com/VictoriaMetrics/helm-charts).
-* [Kubernetes operator for VictoriaMetrics](https://github.com/VictoriaMetrics/operator).
-* [netdata](https://github.com/netdata/netdata) can push data into VictoriaMetrics via `Prometheus remote_write API`.
-  See [these docs](https://github.com/netdata/netdata#integrations).
 * [go-graphite/carbonapi](https://github.com/go-graphite/carbonapi) can use VictoriaMetrics as time series backend.
   See [this example](https://github.com/go-graphite/carbonapi/blob/main/cmd/carbonapi/carbonapi.example.victoriametrics.yaml).
-* [Ansible role for installing cluster VictoriaMetrics (by VictoriaMetrics)](https://github.com/VictoriaMetrics/ansible-playbooks).
-* [Ansible role for installing cluster VictoriaMetrics (by community)](https://github.com/Slapper/ansible-victoriametrics-cluster-role).
-* [Ansible role for installing single-node VictoriaMetrics (by community)](https://github.com/dreamteam-gg/ansible-victoriametrics-role).
-
-* [Snap package for VictoriaMetrics](https://snapcraft.io/victoriametrics).
+* [netdata](https://github.com/netdata/netdata) can push data into VictoriaMetrics via `Prometheus remote_write API`.
+  See [these docs](https://github.com/netdata/netdata#integrations).
 * [vmalert-cli](https://github.com/aorfanos/vmalert-cli) - a CLI application for managing [vmalert](https://docs.victoriametrics.com/vmalert.html).
 
 ## Third-party contributions
@@ -2070,7 +2201,6 @@ Feel free asking any questions regarding VictoriaMetrics:
 * [reddit](https://www.reddit.com/r/VictoriaMetrics/)
 * [telegram-en](https://t.me/VictoriaMetrics_en)
 * [telegram-ru](https://t.me/VictoriaMetrics_ru1)
-* [articles and talks about VictoriaMetrics in Russian](https://github.com/denisgolius/victoriametrics-ru-links)
 * [google groups](https://groups.google.com/forum/#!forum/victorametrics-users)
 
 If you like VictoriaMetrics and want to contribute, then we need the following:
@@ -2130,7 +2260,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
 
 ```
   -bigMergeConcurrency int
-     The maximum number of CPU cores to use for big merges. Default value is used if set to 0
+     Deprecated: this flag does nothing. Please use -smallMergeConcurrency for controlling the concurrency of background merges. See https://docs.victoriametrics.com/#storage
   -cacheExpireDuration duration
      Items are removed from in-memory caches after they aren't accessed for this duration. Lower values may reduce memory usage at the cost of higher CPU usage. See also -prevCacheRemovalPercent (default 30m0s)
   -configAuthKey string
@@ -2147,18 +2277,18 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -deleteAuthKey string
      authKey for metrics' deletion via /api/v1/admin/tsdb/delete_series and /tags/delSeries
   -denyQueriesOutsideRetention
-     Whether to deny queries outside of the configured -retentionPeriod. When set, then /api/v1/query_range would return '503 Service Unavailable' error for queries with 'from' value outside -retentionPeriod. This may be useful when multiple data sources with distinct retentions are hidden behind query-tee
+     Whether to deny queries outside the configured -retentionPeriod. When set, then /api/v1/query_range would return '503 Service Unavailable' error for queries with 'from' value outside -retentionPeriod. This may be useful when multiple data sources with distinct retentions are hidden behind query-tee
   -denyQueryTracing
      Whether to disable the ability to trace queries. See https://docs.victoriametrics.com/#query-tracing
   -downsampling.period array
-     Comma-separated downsampling periods in the format 'offset:period'. For example, '30d:10m' instructs to leave a single sample per 10 minutes for samples older than 30 days. See https://docs.victoriametrics.com/#downsampling for details. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
+     Comma-separated downsampling periods in the format 'offset:period'. For example, '30d:10m' instructs to leave a single sample per 10 minutes for samples older than 30 days. When setting multiple downsampling periods, it is necessary for the periods to be multiples of each other. See https://docs.victoriametrics.com/#downsampling for details. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
      Supports an array of values separated by comma or specified via multiple flags.
   -dryRun
-     Whether to check only -promscrape.config and then exit. Unknown config entries aren't allowed in -promscrape.config by default. This can be changed with -promscrape.config.strictParse=false command-line flag
+     Whether to check config files without running VictoriaMetrics. The following config files are checked: -promscrape.config, -relabelConfig and -streamAggr.config. Unknown config entries aren't allowed in -promscrape.config by default. This can be changed with -promscrape.config.strictParse=false command-line flag
   -enableTCP6
-     Whether to enable IPv6 for listening and dialing. By default only IPv4 TCP and UDP is used
+     Whether to enable IPv6 for listening and dialing. By default, only IPv4 TCP and UDP are used
   -envflag.enable
-     Whether to enable reading flags from environment variables additionally to command line. Command line flag values have priority over values from environment vars. Flags are read only from command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
+     Whether to enable reading flags from environment variables in addition to the command line. Command line flag values have priority over values from environment vars. Flags are read only from the command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
   -envflag.prefix string
      Prefix for environment variables if -envflag.enable is set
   -eula
@@ -2172,7 +2302,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -forceMergeAuthKey string
      authKey, which must be passed in query string to /internal/force_merge pages
   -fs.disableMmap
-     Whether to use pread() instead of mmap() for reading data files. By default mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
+     Whether to use pread() instead of mmap() for reading data files. By default, mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
   -graphiteListenAddr string
      TCP and UDP address to listen for Graphite plaintext data. Usually :2003 must be set. Doesn't work if empty. See also -graphiteListenAddr.useProxyProtocol
   -graphiteListenAddr.useProxyProtocol
@@ -2182,7 +2312,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -http.connTimeout duration
      Incoming http connections are closed after the configured timeout. This may help to spread the incoming load among a cluster of services behind a load balancer. Please note that the real timeout may be bigger by up to 10% as a protection against the thundering herd problem (default 2m0s)
   -http.disableResponseCompression
-     Disable compression of HTTP responses to save CPU resources. By default compression is enabled to save network bandwidth
+     Disable compression of HTTP responses to save CPU resources. By default, compression is enabled to save network bandwidth
   -http.idleConnTimeout duration
      Timeout for incoming idle http connections (default 1m0s)
   -http.maxGracefulShutdownDuration duration
@@ -2192,13 +2322,13 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -http.shutdownDelay duration
      Optional delay before http server shutdown. During this delay, the server returns non-OK responses from /health page, so load balancers can route new requests to other servers
   -httpAuth.password string
-     Password for HTTP Basic Auth. The authentication is disabled if -httpAuth.username is empty
+     Password for HTTP server's Basic Auth. The authentication is disabled if -httpAuth.username is empty
   -httpAuth.username string
-     Username for HTTP Basic Auth. The authentication is disabled if empty. See also -httpAuth.password
+     Username for HTTP server's Basic Auth. The authentication is disabled if empty. See also -httpAuth.password
   -httpListenAddr string
      TCP address to listen for http connections. See also -httpListenAddr.useProxyProtocol (default ":8428")
   -httpListenAddr.useProxyProtocol
-     Whether to use proxy protocol for connections accepted at -httpListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
+     Whether to use proxy protocol for connections accepted at -httpListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt . With enabled proxy protocol http server cannot serve regular /metrics endpoint. Use -pushmetrics.url for metrics pushing
   -import.maxLineLen size
      The maximum length in bytes of a single line accepted by /api/v1/import; the line length can be limited with 'max_rows_per_line' query arg passed to /api/v1/export
      Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 104857600)
@@ -2219,15 +2349,19 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -influxSkipMeasurement
      Uses '{field_name}' as a metric name while ignoring '{measurement}' and '-influxMeasurementFieldSeparator'
   -influxSkipSingleField
-     Uses '{measurement}' instead of '{measurement}{separator}{field_name}' for metic name if InfluxDB line contains only a single field
+     Uses '{measurement}' instead of '{measurement}{separator}{field_name}' for metric name if InfluxDB line contains only a single field
   -influxTrimTimestamp duration
      Trim timestamps for InfluxDB line protocol data to this duration. Minimum practical duration is 1ms. Higher duration (i.e. 1s) may be used for reducing disk space usage for timestamp data (default 1ms)
   -inmemoryDataFlushInterval duration
-     The interval for guaranteed saving of in-memory data to disk. The saved data survives unclean shutdown such as OOM crash, hardware reset, SIGKILL, etc. Bigger intervals may help increasing lifetime of flash storage with limited write cycles (e.g. Raspberry PI). Smaller intervals increase disk IO load. Minimum supported value is 1s (default 5s)
+     The interval for guaranteed saving of in-memory data to disk. The saved data survives unclean shutdowns such as OOM crash, hardware reset, SIGKILL, etc. Bigger intervals may help increase the lifetime of flash storage with limited write cycles (e.g. Raspberry PI). Smaller intervals increase disk IO load. Minimum supported value is 1s (default 5s)
   -insert.maxQueueDuration duration
      The maximum duration to wait in the queue when -maxConcurrentInserts concurrent insert requests are executed (default 1m0s)
+  -internStringCacheExpireDuration duration
+     The expiry duration for caches for interned strings. See https://en.wikipedia.org/wiki/String_interning . See also -internStringMaxLen and -internStringDisableCache (default 6m0s)
+  -internStringDisableCache
+     Whether to disable caches for interned strings. This may reduce memory usage at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning . See also -internStringCacheExpireDuration and -internStringMaxLen
   -internStringMaxLen int
-     The maximum length for strings to intern. Lower limit may save memory at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning (default 300)
+     The maximum length for strings to intern. A lower limit may save memory at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning . See also -internStringDisableCache and -internStringCacheExpireDuration (default 500)
   -logNewSeries
      Whether to log new series. This option is for debug purposes only. It can lead to performance issues when big number of new series are ingested into VictoriaMetrics
   -loggerDisableTimestamps
@@ -2247,7 +2381,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -loggerWarnsPerSecondLimit int
      Per-second limit on the number of WARN messages. If more than the given number of warns are emitted per second, then the remaining warns are suppressed. Zero values disable the rate limit
   -maxConcurrentInserts int
-     The maximum number of concurrent insert requests. Default value should work for most cases, since it minimizes the memory usage. The default value can be increased when clients send data over slow networks. See also -insert.maxQueueDuration (default 8)
+     The maximum number of concurrent insert requests. The default value should work for most cases, since it minimizes memory usage. The default value can be increased when clients send data over slow networks. See also -insert.maxQueueDuration (default 8)
   -maxInsertRequestSize size
      The maximum size in bytes of a single Prometheus remote_write API request
      Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 33554432)
@@ -2256,18 +2390,18 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -maxLabelsPerTimeseries int
      The maximum number of labels accepted per time series. Superfluous labels are dropped. In this case the vm_metrics_with_dropped_labels_total metric at /metrics page is incremented (default 30)
   -memory.allowedBytes size
-     Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to a non-zero value. Too low a value may increase the cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache resulting in higher disk IO usage
+     Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to a non-zero value. Too low a value may increase the cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from the OS page cache resulting in higher disk IO usage
      Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 0)
   -memory.allowedPercent float
-     Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low a value may increase cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache which will result in higher disk IO usage (default 60)
+     Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low a value may increase cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from the OS page cache which will result in higher disk IO usage (default 60)
   -metricsAuthKey string
      Auth key for /metrics endpoint. It must be passed via authKey query arg. It overrides httpAuth.* settings
   -opentsdbHTTPListenAddr string
-     TCP address to listen for OpentTSDB HTTP put requests. Usually :4242 must be set. Doesn't work if empty. See also -opentsdbHTTPListenAddr.useProxyProtocol
+     TCP address to listen for OpenTSDB HTTP put requests. Usually :4242 must be set. Doesn't work if empty. See also -opentsdbHTTPListenAddr.useProxyProtocol
   -opentsdbHTTPListenAddr.useProxyProtocol
      Whether to use proxy protocol for connections accepted at -opentsdbHTTPListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
   -opentsdbListenAddr string
-     TCP and UDP address to listen for OpentTSDB metrics. Telnet put messages and HTTP /api/put messages are simultaneously served on TCP port. Usually :4242 must be set. Doesn't work if empty. See also -opentsdbListenAddr.useProxyProtocol
+     TCP and UDP address to listen for OpenTSDB metrics. Telnet put messages and HTTP /api/put messages are simultaneously served on TCP port. Usually :4242 must be set. Doesn't work if empty. See also -opentsdbListenAddr.useProxyProtocol
   -opentsdbListenAddr.useProxyProtocol
      Whether to use proxy protocol for connections accepted at -opentsdbListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
   -opentsdbTrimTimestamp duration
@@ -2286,9 +2420,9 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -promscrape.azureSDCheckInterval duration
      Interval for checking for changes in Azure. This works only if azure_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#azure_sd_configs for details (default 1m0s)
   -promscrape.cluster.memberNum string
-     The number of number in the cluster of scrapers. It must be an unique value in the range 0 ... promscrape.cluster.membersCount-1 across scrapers in the cluster. Can be specified as pod name of Kubernetes StatefulSet - pod-name-Num, where Num is a numeric part of pod name (default "0")
+     The number of number in the cluster of scrapers. It must be a unique value in the range 0 ... promscrape.cluster.membersCount-1 across scrapers in the cluster. Can be specified as pod name of Kubernetes StatefulSet - pod-name-Num, where Num is a numeric part of pod name (default "0")
   -promscrape.cluster.membersCount int
-     The number of members in a cluster of scrapers. Each member must have an unique -promscrape.cluster.memberNum in the range 0 ... promscrape.cluster.membersCount-1 . Each member then scrapes roughly 1/N of all the targets. By default cluster scraping is disabled, i.e. a single scraper scrapes all the targets
+     The number of members in a cluster of scrapers. Each member must have a unique -promscrape.cluster.memberNum in the range 0 ... promscrape.cluster.membersCount-1 . Each member then scrapes roughly 1/N of all the targets. By default, cluster scraping is disabled, i.e. a single scraper scrapes all the targets
   -promscrape.cluster.name string
      Optional name of the cluster. If multiple vmagent clusters scrape the same targets, then each cluster must have unique name in order to properly de-duplicate samples received from these clusters. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2679
   -promscrape.cluster.replicationFactor int
@@ -2300,17 +2434,19 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -promscrape.config.strictParse
      Whether to deny unsupported fields in -promscrape.config . Set to false in order to silently skip unsupported fields (default true)
   -promscrape.configCheckInterval duration
-     Interval for checking for changes in '-promscrape.config' file. By default the checking is disabled. Send SIGHUP signal in order to force config check for changes
+     Interval for checking for changes in '-promscrape.config' file. By default, the checking is disabled. Send SIGHUP signal in order to force config check for changes
   -promscrape.consul.waitTime duration
      Wait time used by Consul service discovery. Default value is used if not set
   -promscrape.consulSDCheckInterval duration
      Interval for checking for changes in Consul. This works only if consul_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#consul_sd_configs for details (default 30s)
+  -promscrape.consulagentSDCheckInterval duration
+     Interval for checking for changes in Consul Agent. This works only if consulagent_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#consulagent_sd_configs for details (default 30s)
   -promscrape.digitaloceanSDCheckInterval duration
      Interval for checking for changes in digital ocean. This works only if digitalocean_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#digitalocean_sd_configs for details (default 1m0s)
   -promscrape.disableCompression
-     Whether to disable sending 'Accept-Encoding: gzip' request headers to all the scrape targets. This may reduce CPU usage on scrape targets at the cost of higher network bandwidth utilization. It is possible to set 'disable_compression: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control
+     Whether to disable sending 'Accept-Encoding: gzip' request headers to all the scrape targets. This may reduce CPU usage on scrape targets at the cost of higher network bandwidth utilization. It is possible to set 'disable_compression: true' individually per each 'scrape_config' section in '-promscrape.config' for fine-grained control
   -promscrape.disableKeepAlive
-     Whether to disable HTTP keep-alive connections when scraping all the targets. This may be useful when targets has no support for HTTP keep-alive connection. It is possible to set 'disable_keepalive: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control. Note that disabling HTTP keep-alive may increase load on both vmagent and scrape targets
+     Whether to disable HTTP keep-alive connections when scraping all the targets. This may be useful when targets has no support for HTTP keep-alive connection. It is possible to set 'disable_keepalive: true' individually per each 'scrape_config' section in '-promscrape.config' for fine-grained control. Note that disabling HTTP keep-alive may increase load on both vmagent and scrape targets
   -promscrape.discovery.concurrency int
      The maximum number of concurrent requests to Prometheus autodiscovery API (Consul, Kubernetes, etc.) (default 100)
   -promscrape.discovery.concurrentWaitTime duration
@@ -2337,6 +2473,8 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
      How frequently to reload the full state from Kubernetes API server (default 30m0s)
   -promscrape.kubernetesSDCheckInterval duration
      Interval for checking for changes in Kubernetes API server. This works only if kubernetes_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#kubernetes_sd_configs for details (default 30s)
+  -promscrape.kumaSDCheckInterval duration
+     Interval for checking for changes in kuma service discovery. This works only if kuma_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#kuma_sd_configs for details (default 30s)
   -promscrape.maxDroppedTargets int
      The maximum number of droppedTargets to show at /api/v1/targets page. Increase this value if your setup drops more scrape targets during relabeling and you need investigating labels for all the dropped targets. Note that the increased number of tracked dropped targets may result in increased memory usage (default 1000)
   -promscrape.maxResponseHeadersSize size
@@ -2359,7 +2497,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -promscrape.seriesLimitPerTarget int
      Optional limit on the number of unique time series a single scrape target can expose. See https://docs.victoriametrics.com/vmagent.html#cardinality-limiter for more info
   -promscrape.streamParse
-     Whether to enable stream parsing for metrics obtained from scrape targets. This may be useful for reducing memory usage when millions of metrics are exposed per each scrape target. It is posible to set 'stream_parse: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control
+     Whether to enable stream parsing for metrics obtained from scrape targets. This may be useful for reducing memory usage when millions of metrics are exposed per each scrape target. It is possible to set 'stream_parse: true' individually per each 'scrape_config' section in '-promscrape.config' for fine-grained control
   -promscrape.suppressDuplicateScrapeTargetErrors
      Whether to suppress 'duplicate scrape target' errors; see https://docs.victoriametrics.com/vmagent.html#troubleshooting for details
   -promscrape.suppressScrapeErrors
@@ -2374,7 +2512,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -pushmetrics.interval duration
      Interval for pushing metrics to -pushmetrics.url (default 10s)
   -pushmetrics.url array
-     Optional URL to push metrics exposed at /metrics page. See https://docs.victoriametrics.com/#push-metrics . By default metrics exposed at /metrics page aren't pushed to any remote storage
+     Optional URL to push metrics exposed at /metrics page. See https://docs.victoriametrics.com/#push-metrics . By default, metrics exposed at /metrics page aren't pushed to any remote storage
      Supports an array of values separated by comma or specified via multiple flags.
   -relabelConfig string
      Optional path to a file with relabeling rules, which are applied to all the ingested metrics. The path can point either to local file or to http url. See https://docs.victoriametrics.com/#relabeling for details. The config is reloaded on SIGHUP signal
@@ -2382,7 +2520,7 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
      Retention filter in the format 'filter:retention'. For example, '{env="dev"}:3d' configures the retention for time series with env="dev" label to 3 days. See https://docs.victoriametrics.com/#retention-filters for details. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
      Supports an array of values separated by comma or specified via multiple flags.
   -retentionPeriod value
-     Data with timestamps outside the retentionPeriod is automatically deleted. See also -retentionFilter
+     Data with timestamps outside the retentionPeriod is automatically deleted. The minimum retentionPeriod is 24h or 1d. See also -retentionFilter
      The following optional suffixes are supported: h (hour), d (day), w (week), y (year). If suffix isn't set, then the duration is counted in months (default 1)
   -retentionTimezoneOffset duration
      The offset for performing indexdb rotation. If set to 0, then the indexdb rotation is performed at 4am UTC time per each -retentionPeriod. If set to 2h, then the indexdb rotation is performed at 4am EET time (the timezone with +2h offset)
@@ -2393,13 +2531,16 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -search.disableCache
      Whether to disable response caching. This may be useful during data backfilling
   -search.graphiteMaxPointsPerSeries int
-     The maximum number of points per series Graphite render API can return. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html (default 1000000)
+     The maximum number of points per series Graphite render API can return (default 1000000)
   -search.graphiteStorageStep duration
-     The interval between datapoints stored in the database. It is used at Graphite Render API handler for normalizing the interval between datapoints in case it isn't normalized. It can be overridden by sending 'storage_step' query arg to /render API or by sending the desired interval via 'Storage-Step' http header during querying /render API. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html (default 10s)
+     The interval between datapoints stored in the database. It is used at Graphite Render API handler for normalizing the interval between datapoints in case it isn't normalized. It can be overridden by sending 'storage_step' query arg to /render API or by sending the desired interval via 'Storage-Step' http header during querying /render API (default 10s)
   -search.latencyOffset duration
      The time when data points become visible in query results after the collection. It can be overridden on per-query basis via latency_offset arg. Too small value can result in incomplete last points for query results (default 30s)
+  -search.logQueryMemoryUsage size
+     Log queries, which require more memory than specified by this flag. This may help detecting and optimizing heavy queries. Query logging is disabled by default. See also -search.logSlowQueryDuration and -search.maxMemoryPerQuery
+     Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 0)
   -search.logSlowQueryDuration duration
-     Log queries with execution time exceeding this value. Zero disables slow query logging (default 5s)
+     Log queries with execution time exceeding this value. Zero disables slow query logging. See also -search.logQueryMemoryUsage (default 5s)
   -search.maxConcurrentRequests int
      The maximum number of concurrent search requests. It shouldn't be high, since a single request can saturate all the CPU cores, while many concurrently executed requests may require high amounts of memory. See also -search.maxQueueDuration and -search.maxMemoryPerQuery (default 8)
   -search.maxExportDuration duration
@@ -2409,11 +2550,15 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -search.maxFederateSeries int
      The maximum number of time series, which can be returned from /federate. This option allows limiting memory usage (default 1000000)
   -search.maxGraphiteSeries int
-     The maximum number of time series, which can be scanned during queries to Graphite Render API. See https://docs.victoriametrics.com/#graphite-render-api-usage . This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html (default 300000)
+     The maximum number of time series, which can be scanned during queries to Graphite Render API. See https://docs.victoriametrics.com/#graphite-render-api-usage (default 300000)
+  -search.maxGraphiteTagKeys int
+     The maximum number of tag keys returned from Graphite API, which returns tags. See https://docs.victoriametrics.com/#graphite-tags-api-usage (default 100000)
+  -search.maxGraphiteTagValues int
+     The maximum number of tag values returned from Graphite API, which returns tag values. See https://docs.victoriametrics.com/#graphite-tags-api-usage (default 100000)
   -search.maxLookback duration
-     Synonym to -search.lookback-delta from Prometheus. The value is dynamically detected from interval between time series datapoints if not set. It can be overridden on per-query basis via max_lookback arg. See also '-search.maxStalenessInterval' flag, which has the same meaining due to historical reasons
+     Synonym to -search.lookback-delta from Prometheus. The value is dynamically detected from interval between time series datapoints if not set. It can be overridden on per-query basis via max_lookback arg. See also '-search.maxStalenessInterval' flag, which has the same meaning due to historical reasons
   -search.maxMemoryPerQuery size
-     The maximum amounts of memory a single query may consume. Queries requiring more memory are rejected. The total memory limit for concurrently executed queries can be estimated as -search.maxMemoryPerQuery multiplied by -search.maxConcurrentRequests
+     The maximum amounts of memory a single query may consume. Queries requiring more memory are rejected. The total memory limit for concurrently executed queries can be estimated as -search.maxMemoryPerQuery multiplied by -search.maxConcurrentRequests . See also -search.logQueryMemoryUsage
      Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 0)
   -search.maxPointsPerTimeseries int
      The maximum points per a single timeseries returned from /api/v1/query_range. This option doesn't limit the number of scanned raw samples in the database. The main purpose of this option is to limit the number of per-series points returned to graphing UI such as VMUI or Grafana. There is no sense in setting this limit to values bigger than the horizontal resolution of the graph (default 30000)
@@ -2432,8 +2577,10 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
      The maximum number of raw samples a single query can scan per each time series. This option allows limiting memory usage (default 30000000)
   -search.maxSeries int
      The maximum number of time series, which can be returned from /api/v1/series. This option allows limiting memory usage (default 30000)
+  -search.maxSeriesPerAggrFunc int
+     The maximum number of time series an aggregate MetricsQL function can generate (default 1000000)
   -search.maxStalenessInterval duration
-     The maximum interval for staleness calculations. By default it is automatically calculated from the median interval between samples. This flag could be useful for tuning Prometheus data model closer to Influx-style data model. See https://prometheus.io/docs/prometheus/latest/querying/basics/#staleness for details. See also '-search.setLookbackToStep' flag
+     The maximum interval for staleness calculations. By default, it is automatically calculated from the median interval between samples. This flag could be useful for tuning Prometheus data model closer to Influx-style data model. See https://prometheus.io/docs/prometheus/latest/querying/basics/#staleness for details. See also '-search.setLookbackToStep' flag
   -search.maxStatusRequestDuration duration
      The maximum duration for /api/v1/status/* requests (default 5m0s)
   -search.maxStepForPointsAdjustment duration
@@ -2469,9 +2616,11 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -selfScrapeJob string
      Value for 'job' label, which is added to self-scraped metrics (default "victoria-metrics")
   -smallMergeConcurrency int
-     The maximum number of CPU cores to use for small merges. Default value is used if set to 0
+     The maximum number of workers for background merges. See https://docs.victoriametrics.com/#storage . It isn't recommended tuning this flag in general case, since this may lead to uncontrolled increase in the number of parts and increased CPU usage during queries
   -snapshotAuthKey string
      authKey, which must be passed in query string to /snapshot* pages
+  -snapshotCreateTimeout duration
+     The timeout for creating new snapshot. If set, make sure that timeout is lower than backup period
   -snapshotsMaxAge value
      Automatically delete snapshots older than -snapshotsMaxAge if it is set to non-zero duration. Make sure that backup process has enough time to finish the backup before the corresponding snapshot is automatically deleted
      The following optional suffixes are supported: h (hour), d (day), w (week), y (year). If suffix isn't set, then the duration is counted in months (default 0)
@@ -2499,11 +2648,13 @@ Pass `-help` to VictoriaMetrics in order to see the list of supported command-li
   -storageDataPath string
      Path to storage data (default "victoria-metrics-data")
   -streamAggr.config string
-     Optional path to file with stream aggregation config. See https://docs.victoriametrics.com/stream-aggregation.html . See also -remoteWrite.streamAggr.keepInput and -streamAggr.dedupInterval
+     Optional path to file with stream aggregation config. See https://docs.victoriametrics.com/stream-aggregation.html . See also -streamAggr.keepInput, -streamAggr.dropInput and -streamAggr.dedupInterval
   -streamAggr.dedupInterval duration
      Input samples are de-duplicated with this interval before being aggregated. Only the last sample per each time series per each interval is aggregated if the interval is greater than zero
+  -streamAggr.dropInput
+     Whether to drop all the input samples after the aggregation with -streamAggr.config. By default, only aggregated samples are dropped, while the remaining samples are stored in the database. See also -streamAggr.keepInput and https://docs.victoriametrics.com/stream-aggregation.html
   -streamAggr.keepInput
-     Whether to keep input samples after the aggregation with -streamAggr.config. By default the input is dropped after the aggregation, so only the aggregate data is stored. See https://docs.victoriametrics.com/stream-aggregation.html
+     Whether to keep all the input samples after the aggregation with -streamAggr.config. By default, only aggregated samples are dropped, while the remaining samples are stored in the database. See also -streamAggr.dropInput and https://docs.victoriametrics.com/stream-aggregation.html
   -tls
      Whether to enable TLS for incoming HTTP requests at -httpListenAddr (aka https). -tlsCertFile and -tlsKeyFile must be set if -tls is set
   -tlsCertFile string

SECURITY.md

@@ -4,10 +4,10 @@
 
 | Version | Supported          |
 |---------|--------------------|
-| 1.81.x  | :white_check_mark: |
-| 1.80.x  | :x:                |
-| 1.79.x  | :white_check_mark: |
-| < 1.78  | :x:                |
+| [latest release](https://docs.victoriametrics.com/CHANGELOG.html) | :white_check_mark: |
+| v1.87.x LTS release | :white_check_mark: |
+| v1.79.x LTS release | :white_check_mark: |
+| other releases  | :x:                |
 
 ## Reporting a Vulnerability
 

app/victoria-logs/Makefile

@@ -0,0 +1,103 @@
+# All these commands must run from repository root.
+
+victoria-logs:
+	APP_NAME=victoria-logs $(MAKE) app-local
+
+victoria-logs-race:
+	APP_NAME=victoria-logs RACE=-race $(MAKE) app-local
+
+victoria-logs-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker
+
+victoria-logs-pure-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-pure
+
+victoria-logs-linux-amd64-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-linux-amd64
+
+victoria-logs-linux-arm-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-linux-arm
+
+victoria-logs-linux-arm64-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-linux-arm64
+
+victoria-logs-linux-ppc64le-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-linux-ppc64le
+
+victoria-logs-linux-386-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-linux-386
+
+victoria-logs-darwin-amd64-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-darwin-amd64
+
+victoria-logs-darwin-arm64-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-darwin-arm64
+
+victoria-logs-freebsd-amd64-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-freebsd-amd64
+
+victoria-logs-openbsd-amd64-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-openbsd-amd64
+
+victoria-logs-windows-amd64-prod:
+	APP_NAME=victoria-logs $(MAKE) app-via-docker-windows-amd64
+
+package-victoria-logs:
+	APP_NAME=victoria-logs $(MAKE) package-via-docker
+
+package-victoria-logs-pure:
+	APP_NAME=victoria-logs $(MAKE) package-via-docker-pure
+
+package-victoria-logs-amd64:
+	APP_NAME=victoria-logs $(MAKE) package-via-docker-amd64
+
+package-victoria-logs-arm:
+	APP_NAME=victoria-logs $(MAKE) package-via-docker-arm
+
+package-victoria-logs-arm64:
+	APP_NAME=victoria-logs $(MAKE) package-via-docker-arm64
+
+package-victoria-logs-ppc64le:
+	APP_NAME=victoria-logs $(MAKE) package-via-docker-ppc64le
+
+package-victoria-logs-386:
+	APP_NAME=victoria-logs $(MAKE) package-via-docker-386
+
+publish-victoria-logs:
+	APP_NAME=victoria-logs $(MAKE) publish-via-docker
+
+victoria-logs-linux-amd64:
+	APP_NAME=victoria-logs CGO_ENABLED=1 GOOS=linux GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+victoria-logs-linux-arm:
+	APP_NAME=victoria-logs CGO_ENABLED=0 GOOS=linux GOARCH=arm $(MAKE) app-local-goos-goarch
+
+victoria-logs-linux-arm64:
+	APP_NAME=victoria-logs CGO_ENABLED=0 GOOS=linux GOARCH=arm64 $(MAKE) app-local-goos-goarch
+
+victoria-logs-linux-ppc64le:
+	APP_NAME=victoria-logs CGO_ENABLED=0 GOOS=linux GOARCH=ppc64le $(MAKE) app-local-goos-goarch
+
+victoria-logs-linux-s390x:
+	APP_NAME=victoria-logs CGO_ENABLED=0 GOOS=linux GOARCH=s390x $(MAKE) app-local-goos-goarch
+
+victoria-logs-linux-386:
+	APP_NAME=victoria-logs CGO_ENABLED=0 GOOS=linux GOARCH=386 $(MAKE) app-local-goos-goarch
+
+victoria-logs-darwin-amd64:
+	APP_NAME=victoria-logs CGO_ENABLED=0 GOOS=darwin GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+victoria-logs-darwin-arm64:
+	APP_NAME=victoria-logs CGO_ENABLED=0 GOOS=darwin GOARCH=arm64 $(MAKE) app-local-goos-goarch
+
+victoria-logs-freebsd-amd64:
+	APP_NAME=victoria-logs CGO_ENABLED=0 GOOS=freebsd GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+victoria-logs-openbsd-amd64:
+	APP_NAME=victoria-logs CGO_ENABLED=0 GOOS=openbsd GOARCH=amd64 $(MAKE) app-local-goos-goarch
+
+victoria-logs-windows-amd64:
+	GOARCH=amd64 APP_NAME=victoria-logs $(MAKE) app-local-windows-goarch
+
+victoria-logs-pure:
+	APP_NAME=victoria-logs $(MAKE) app-local-pure

app/victoria-logs/deployment/Dockerfile

@@ -0,0 +1,8 @@
+ARG base_image
+FROM $base_image
+
+EXPOSE 8428
+
+ENTRYPOINT ["/victoria-logs-prod"]
+ARG src_binary
+COPY $src_binary ./victoria-logs-prod

app/victoria-logs/main.go

@@ -0,0 +1,103 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlinsert"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlselect"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/buildinfo"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/envflag"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/fs"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/procutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/pushmetrics"
+)
+
+var (
+	httpListenAddr   = flag.String("httpListenAddr", ":9428", "TCP address to listen for http connections. See also -httpListenAddr.useProxyProtocol")
+	useProxyProtocol = flag.Bool("httpListenAddr.useProxyProtocol", false, "Whether to use proxy protocol for connections accepted at -httpListenAddr . "+
+		"See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt . "+
+		"With enabled proxy protocol http server cannot serve regular /metrics endpoint. Use -pushmetrics.url for metrics pushing")
+	gogc = flag.Int("gogc", 100, "GOGC to use. See https://tip.golang.org/doc/gc-guide")
+)
+
+func main() {
+	// Write flags and help message to stdout, since it is easier to grep or pipe.
+	flag.CommandLine.SetOutput(os.Stdout)
+	flag.Usage = usage
+	envflag.Parse()
+	cgroup.SetGOGC(*gogc)
+	buildinfo.Init()
+	logger.Init()
+	pushmetrics.Init()
+
+	logger.Infof("starting VictoriaLogs at %q...", *httpListenAddr)
+	startTime := time.Now()
+
+	vlstorage.Init()
+	vlselect.Init()
+	vlinsert.Init()
+
+	go httpserver.Serve(*httpListenAddr, *useProxyProtocol, requestHandler)
+	logger.Infof("started VictoriaLogs in %.3f seconds; see https://docs.victoriametrics.com/VictoriaLogs/", time.Since(startTime).Seconds())
+
+	sig := procutil.WaitForSigterm()
+	logger.Infof("received signal %s", sig)
+
+	logger.Infof("gracefully shutting down webservice at %q", *httpListenAddr)
+	startTime = time.Now()
+	if err := httpserver.Stop(*httpListenAddr); err != nil {
+		logger.Fatalf("cannot stop the webservice: %s", err)
+	}
+	logger.Infof("successfully shut down the webservice in %.3f seconds", time.Since(startTime).Seconds())
+
+	vlinsert.Stop()
+	vlselect.Stop()
+	vlstorage.Stop()
+
+	fs.MustStopDirRemover()
+
+	logger.Infof("the VictoriaLogs has been stopped in %.3f seconds", time.Since(startTime).Seconds())
+}
+
+func requestHandler(w http.ResponseWriter, r *http.Request) bool {
+	if r.URL.Path == "/" {
+		if r.Method != http.MethodGet {
+			return false
+		}
+		w.Header().Add("Content-Type", "text/html; charset=utf-8")
+		fmt.Fprintf(w, "<h2>Single-node VictoriaLogs</h2></br>")
+		fmt.Fprintf(w, "See docs at <a href='https://docs.victoriametrics.com/VictoriaLogs/'>https://docs.victoriametrics.com/VictoriaLogs/</a></br>")
+		fmt.Fprintf(w, "Useful endpoints:</br>")
+		httpserver.WriteAPIHelp(w, [][2]string{
+			{"select/vmui", "Web UI for VictoriaLogs"},
+			{"metrics", "available service metrics"},
+			{"flags", "command-line flags"},
+		})
+		return true
+	}
+	if vlinsert.RequestHandler(w, r) {
+		return true
+	}
+	if vlselect.RequestHandler(w, r) {
+		return true
+	}
+	return false
+}
+
+func usage() {
+	const s = `
+victoria-logs is a log management and analytics service.
+
+See the docs at https://docs.victoriametrics.com/VictoriaLogs/
+`
+	flagutil.Usage(s)
+}

app/victoria-logs/multiarch/Dockerfile

@@ -0,0 +1,12 @@
+# See https://medium.com/on-docker/use-multi-stage-builds-to-inject-ca-certs-ad1e8f01de1b
+ARG certs_image
+ARG root_image
+FROM $certs_image as certs
+RUN apk update && apk upgrade && apk --update --no-cache add ca-certificates
+
+FROM $root_image
+COPY --from=certs /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
+EXPOSE 8428
+ENTRYPOINT ["/victoria-logs-prod"]
+ARG TARGETARCH
+COPY victoria-logs-linux-${TARGETARCH}-prod ./victoria-logs-prod

app/victoria-metrics/Makefile

@@ -39,6 +39,9 @@ victoria-metrics-freebsd-amd64-prod:
 victoria-metrics-openbsd-amd64-prod:
 	APP_NAME=victoria-metrics $(MAKE) app-via-docker-openbsd-amd64
 
+victoria-metrics-windows-amd64-prod:
+	APP_NAME=victoria-metrics $(MAKE) app-via-docker-windows-amd64
+
 package-victoria-metrics:
 	APP_NAME=victoria-metrics $(MAKE) package-via-docker
 
@@ -82,6 +85,9 @@ victoria-metrics-linux-arm64:
 victoria-metrics-linux-ppc64le:
 	APP_NAME=victoria-metrics CGO_ENABLED=0 GOOS=linux GOARCH=ppc64le $(MAKE) app-local-goos-goarch
 
+victoria-metrics-linux-s390x:
+	APP_NAME=victoria-metrics CGO_ENABLED=0 GOOS=linux GOARCH=s390x $(MAKE) app-local-goos-goarch
+
 victoria-metrics-linux-386:
 	APP_NAME=victoria-metrics CGO_ENABLED=0 GOOS=linux GOARCH=386 $(MAKE) app-local-goos-goarch
 
@@ -97,6 +103,9 @@ victoria-metrics-freebsd-amd64:
 victoria-metrics-openbsd-amd64:
 	APP_NAME=victoria-metrics CGO_ENABLED=0 GOOS=openbsd GOARCH=amd64 $(MAKE) app-local-goos-goarch
 
+victoria-metrics-windows-amd64:
+	GOARCH=amd64 APP_NAME=victoria-metrics $(MAKE) app-local-windows-goarch
+
 victoria-metrics-pure:
 	APP_NAME=victoria-metrics $(MAKE) app-local-pure
 

app/victoria-metrics/main.go

@@ -8,6 +8,8 @@ import (
 	"time"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vminsert"
+	vminsertcommon "github.com/VictoriaMetrics/VictoriaMetrics/app/vminsert/common"
+	vminsertrelabel "github.com/VictoriaMetrics/VictoriaMetrics/app/vminsert/relabel"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/promql"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmstorage"
@@ -26,14 +28,16 @@ import (
 var (
 	httpListenAddr   = flag.String("httpListenAddr", ":8428", "TCP address to listen for http connections. See also -httpListenAddr.useProxyProtocol")
 	useProxyProtocol = flag.Bool("httpListenAddr.useProxyProtocol", false, "Whether to use proxy protocol for connections accepted at -httpListenAddr . "+
-		"See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt")
+		"See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt . "+
+		"With enabled proxy protocol http server cannot serve regular /metrics endpoint. Use -pushmetrics.url for metrics pushing")
 	minScrapeInterval = flag.Duration("dedup.minScrapeInterval", 0, "Leave only the last sample in every time series per each discrete interval "+
 		"equal to -dedup.minScrapeInterval > 0. See https://docs.victoriametrics.com/#deduplication and https://docs.victoriametrics.com/#downsampling")
-	dryRun = flag.Bool("dryRun", false, "Whether to check only -promscrape.config and then exit. "+
-		"Unknown config entries aren't allowed in -promscrape.config by default. This can be changed with -promscrape.config.strictParse=false command-line flag")
+	dryRun = flag.Bool("dryRun", false, "Whether to check config files without running VictoriaMetrics. The following config files are checked: "+
+		"-promscrape.config, -relabelConfig and -streamAggr.config. Unknown config entries aren't allowed in -promscrape.config by default. "+
+		"This can be changed with -promscrape.config.strictParse=false command-line flag")
 	inmemoryDataFlushInterval = flag.Duration("inmemoryDataFlushInterval", 5*time.Second, "The interval for guaranteed saving of in-memory data to disk. "+
-		"The saved data survives unclean shutdown such as OOM crash, hardware reset, SIGKILL, etc. "+
-		"Bigger intervals may help increasing lifetime of flash storage with limited write cycles (e.g. Raspberry PI). "+
+		"The saved data survives unclean shutdowns such as OOM crash, hardware reset, SIGKILL, etc. "+
+		"Bigger intervals may help increase the lifetime of flash storage with limited write cycles (e.g. Raspberry PI). "+
 		"Smaller intervals increase disk IO load. Minimum supported value is 1s")
 )
 
@@ -53,7 +57,13 @@ func main() {
 		if err := promscrape.CheckConfig(); err != nil {
 			logger.Fatalf("error when checking -promscrape.config: %s", err)
 		}
-		logger.Infof("-promscrape.config is ok; exitting with 0 status code")
+		if err := vminsertrelabel.CheckRelabelConfig(); err != nil {
+			logger.Fatalf("error when checking -relabelConfig: %s", err)
+		}
+		if err := vminsertcommon.CheckStreamAggrConfig(); err != nil {
+			logger.Fatalf("error when checking -streamAggr.config: %s", err)
+		}
+		logger.Infof("-promscrape.config is ok; exiting with 0 status code")
 		return
 	}
 
@@ -92,7 +102,7 @@ func main() {
 
 func requestHandler(w http.ResponseWriter, r *http.Request) bool {
 	if r.URL.Path == "/" {
-		if r.Method != "GET" {
+		if r.Method != http.MethodGet {
 			return false
 		}
 		w.Header().Add("Content-Type", "text/html; charset=utf-8")

app/vlinsert/elasticsearch/bulk_response.qtpl

@@ -0,0 +1,20 @@
+{% stripspace %}
+
+{% func BulkResponse(n int, tookMs int64) %}
+{
+	"took":{%dl tookMs %},
+	"errors":false,
+	"items":[
+		{% for i := 0; i < n; i++ %}
+		{
+			"create":{
+				"status":201
+			}
+		}
+		{% if i+1 < n %},{% endif %}
+		{% endfor %}
+	]
+}
+{% endfunc %}
+
+{% endstripspace %}

app/vlinsert/elasticsearch/bulk_response.qtpl.go

@@ -0,0 +1,69 @@
+// Code generated by qtc from "bulk_response.qtpl". DO NOT EDIT.
+// See https://github.com/valyala/quicktemplate for details.
+
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:3
+package elasticsearch
+
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:3
+import (
+	qtio422016 "io"
+
+	qt422016 "github.com/valyala/quicktemplate"
+)
+
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:3
+var (
+	_ = qtio422016.Copy
+	_ = qt422016.AcquireByteBuffer
+)
+
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:3
+func StreamBulkResponse(qw422016 *qt422016.Writer, n int, tookMs int64) {
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:3
+	qw422016.N().S(`{"took":`)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:5
+	qw422016.N().DL(tookMs)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:5
+	qw422016.N().S(`,"errors":false,"items":[`)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:8
+	for i := 0; i < n; i++ {
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:8
+		qw422016.N().S(`{"create":{"status":201}}`)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:14
+		if i+1 < n {
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:14
+			qw422016.N().S(`,`)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:14
+		}
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:15
+	}
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:15
+	qw422016.N().S(`]}`)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+}
+
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+func WriteBulkResponse(qq422016 qtio422016.Writer, n int, tookMs int64) {
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+	qw422016 := qt422016.AcquireWriter(qq422016)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+	StreamBulkResponse(qw422016, n, tookMs)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+	qt422016.ReleaseWriter(qw422016)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+}
+
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+func BulkResponse(n int, tookMs int64) string {
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+	qb422016 := qt422016.AcquireByteBuffer()
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+	WriteBulkResponse(qb422016, n, tookMs)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+	qs422016 := string(qb422016.B)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+	qt422016.ReleaseByteBuffer(qb422016)
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+	return qs422016
+//line app/vlinsert/elasticsearch/bulk_response.qtpl:18
+}

app/vlinsert/elasticsearch/elasticsearch.go

@@ -0,0 +1,264 @@
+package elasticsearch
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"math"
+	"net/http"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlinsert/insertutils"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bufferedwriter"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logjson"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/writeconcurrencylimiter"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+// RequestHandler processes Elasticsearch insert requests
+func RequestHandler(path string, w http.ResponseWriter, r *http.Request) bool {
+	w.Header().Add("Content-Type", "application/json")
+	// This header is needed for Logstash
+	w.Header().Set("X-Elastic-Product", "Elasticsearch")
+
+	if strings.HasPrefix(path, "/_ilm/policy") {
+		// Return fake response for Elasticsearch ilm request.
+		fmt.Fprintf(w, `{}`)
+		return true
+	}
+	if strings.HasPrefix(path, "/_index_template") {
+		// Return fake response for Elasticsearch index template request.
+		fmt.Fprintf(w, `{}`)
+		return true
+	}
+	if strings.HasPrefix(path, "/_ingest") {
+		// Return fake response for Elasticsearch ingest pipeline request.
+		// See: https://www.elastic.co/guide/en/elasticsearch/reference/8.8/put-pipeline-api.html
+		fmt.Fprintf(w, `{}`)
+		return true
+	}
+	if strings.HasPrefix(path, "/_nodes") {
+		// Return fake response for Elasticsearch nodes discovery request.
+		// See: https://www.elastic.co/guide/en/elasticsearch/reference/8.8/cluster.html
+		fmt.Fprintf(w, `{}`)
+		return true
+	}
+	switch path {
+	case "/":
+		switch r.Method {
+		case http.MethodGet:
+			// Return fake response for Elasticsearch ping request.
+			// See the latest available version for Elasticsearch at https://github.com/elastic/elasticsearch/releases
+			fmt.Fprintf(w, `{
+			"version": {
+				"number": "8.8.0"
+			}
+		}`)
+		case http.MethodHead:
+			// Return empty response for Logstash ping request.
+		}
+
+		return true
+	case "/_license":
+		// Return fake response for Elasticsearch license request.
+		fmt.Fprintf(w, `{
+			"license": {
+				"uid": "cbff45e7-c553-41f7-ae4f-9205eabd80xx",
+				"type": "oss",
+				"status": "active",
+				"expiry_date_in_millis" : 4000000000000
+			}
+		}`)
+		return true
+	case "/_bulk":
+		startTime := time.Now()
+		bulkRequestsTotal.Inc()
+
+		cp, err := insertutils.GetCommonParams(r)
+		if err != nil {
+			httpserver.Errorf(w, r, "%s", err)
+			return true
+		}
+		lr := logstorage.GetLogRows(cp.StreamFields, cp.IgnoreFields)
+		processLogMessage := cp.GetProcessLogMessageFunc(lr)
+		isGzip := r.Header.Get("Content-Encoding") == "gzip"
+		n, err := readBulkRequest(r.Body, isGzip, cp.TimeField, cp.MsgField, processLogMessage)
+		if err != nil {
+			logger.Warnf("cannot decode log message #%d in /_bulk request: %s", n, err)
+			return true
+		}
+		vlstorage.MustAddRows(lr)
+		logstorage.PutLogRows(lr)
+
+		tookMs := time.Since(startTime).Milliseconds()
+		bw := bufferedwriter.Get(w)
+		defer bufferedwriter.Put(bw)
+		WriteBulkResponse(bw, n, tookMs)
+		_ = bw.Flush()
+		return true
+	default:
+		return false
+	}
+}
+
+var (
+	bulkRequestsTotal = metrics.NewCounter(`vl_http_requests_total{path="/insert/elasticsearch/_bulk"}`)
+)
+
+func readBulkRequest(r io.Reader, isGzip bool, timeField, msgField string,
+	processLogMessage func(timestamp int64, fields []logstorage.Field),
+) (int, error) {
+	// See https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-bulk.html
+
+	if isGzip {
+		zr, err := common.GetGzipReader(r)
+		if err != nil {
+			return 0, fmt.Errorf("cannot read gzipped _bulk request: %w", err)
+		}
+		defer common.PutGzipReader(zr)
+		r = zr
+	}
+
+	wcr := writeconcurrencylimiter.GetReader(r)
+	defer writeconcurrencylimiter.PutReader(wcr)
+
+	lb := lineBufferPool.Get()
+	defer lineBufferPool.Put(lb)
+
+	lb.B = bytesutil.ResizeNoCopyNoOverallocate(lb.B, insertutils.MaxLineSizeBytes.IntN())
+	sc := bufio.NewScanner(wcr)
+	sc.Buffer(lb.B, len(lb.B))
+
+	n := 0
+	nCheckpoint := 0
+	for {
+		ok, err := readBulkLine(sc, timeField, msgField, processLogMessage)
+		wcr.DecConcurrency()
+		if err != nil || !ok {
+			rowsIngestedTotal.Add(n - nCheckpoint)
+			return n, err
+		}
+		n++
+		if batchSize := n - nCheckpoint; n >= 1000 {
+			rowsIngestedTotal.Add(batchSize)
+			nCheckpoint = n
+		}
+	}
+}
+
+var lineBufferPool bytesutil.ByteBufferPool
+
+var rowsIngestedTotal = metrics.NewCounter(`vl_rows_ingested_total{type="elasticsearch_bulk"}`)
+
+func readBulkLine(sc *bufio.Scanner, timeField, msgField string,
+	processLogMessage func(timestamp int64, fields []logstorage.Field),
+) (bool, error) {
+	var line []byte
+
+	// Read the command, must be "create" or "index"
+	for len(line) == 0 {
+		if !sc.Scan() {
+			if err := sc.Err(); err != nil {
+				if errors.Is(err, bufio.ErrTooLong) {
+					return false, fmt.Errorf(`cannot read "create" or "index" command, since its size exceeds -insert.maxLineSizeBytes=%d`,
+						insertutils.MaxLineSizeBytes.IntN())
+				}
+				return false, err
+			}
+			return false, nil
+		}
+		line = sc.Bytes()
+	}
+	lineStr := bytesutil.ToUnsafeString(line)
+	if !strings.Contains(lineStr, `"create"`) && !strings.Contains(lineStr, `"index"`) {
+		return false, fmt.Errorf(`unexpected command %q; expecting "create" or "index"`, line)
+	}
+
+	// Decode log message
+	if !sc.Scan() {
+		if err := sc.Err(); err != nil {
+			if errors.Is(err, bufio.ErrTooLong) {
+				return false, fmt.Errorf("cannot read log message, since its size exceeds -insert.maxLineSizeBytes=%d", insertutils.MaxLineSizeBytes.IntN())
+			}
+			return false, err
+		}
+		return false, fmt.Errorf(`missing log message after the "create" or "index" command`)
+	}
+	line = sc.Bytes()
+	p := logjson.GetParser()
+	if err := p.ParseLogMessage(line); err != nil {
+		return false, fmt.Errorf("cannot parse json-encoded log entry: %w", err)
+	}
+
+	ts, err := extractTimestampFromFields(timeField, p.Fields)
+	if err != nil {
+		return false, fmt.Errorf("cannot parse timestamp: %w", err)
+	}
+	if ts == 0 {
+		ts = time.Now().UnixNano()
+	}
+	p.RenameField(msgField, "_msg")
+	processLogMessage(ts, p.Fields)
+	logjson.PutParser(p)
+	return true, nil
+}
+
+func extractTimestampFromFields(timeField string, fields []logstorage.Field) (int64, error) {
+	for i := range fields {
+		f := &fields[i]
+		if f.Name != timeField {
+			continue
+		}
+		timestamp, err := parseElasticsearchTimestamp(f.Value)
+		if err != nil {
+			return 0, err
+		}
+		f.Value = ""
+		return timestamp, nil
+	}
+	return 0, nil
+}
+
+func parseElasticsearchTimestamp(s string) (int64, error) {
+	if s == "0" || s == "" {
+		// Special case - zero or empty timestamp must be substituted
+		// with the current time by the caller.
+		return 0, nil
+	}
+	if len(s) < len("YYYY-MM-DD") || s[len("YYYY")] != '-' {
+		// Try parsing timestamp in milliseconds
+		n, err := strconv.ParseInt(s, 10, 64)
+		if err != nil {
+			return 0, fmt.Errorf("cannot parse timestamp in milliseconds from %q: %w", s, err)
+		}
+		if n > int64(math.MaxInt64)/1e6 {
+			return 0, fmt.Errorf("too big timestamp in milliseconds: %d; mustn't exceed %d", n, int64(math.MaxInt64)/1e6)
+		}
+		if n < int64(math.MinInt64)/1e6 {
+			return 0, fmt.Errorf("too small timestamp in milliseconds: %d; must be bigger than %d", n, int64(math.MinInt64)/1e6)
+		}
+		n *= 1e6
+		return n, nil
+	}
+	if len(s) == len("YYYY-MM-DD") {
+		t, err := time.Parse("2006-01-02", s)
+		if err != nil {
+			return 0, fmt.Errorf("cannot parse date %q: %w", s, err)
+		}
+		return t.UnixNano(), nil
+	}
+	t, err := time.Parse(time.RFC3339, s)
+	if err != nil {
+		return 0, fmt.Errorf("cannot parse timestamp %q: %w", s, err)
+	}
+	return t.UnixNano(), nil
+}

app/vlinsert/elasticsearch/elasticsearch_test.go

@@ -0,0 +1,129 @@
+package elasticsearch
+
+import (
+	"bytes"
+	"compress/gzip"
+	"fmt"
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+)
+
+func TestReadBulkRequestFailure(t *testing.T) {
+	f := func(data string) {
+		t.Helper()
+
+		processLogMessage := func(timestamp int64, fields []logstorage.Field) {
+			t.Fatalf("unexpected call to processLogMessage with timestamp=%d, fields=%s", timestamp, fields)
+		}
+
+		r := bytes.NewBufferString(data)
+		rows, err := readBulkRequest(r, false, "_time", "_msg", processLogMessage)
+		if err == nil {
+			t.Fatalf("expecting non-empty error")
+		}
+		if rows != 0 {
+			t.Fatalf("unexpected non-zero rows=%d", rows)
+		}
+	}
+	f("foobar")
+	f(`{}`)
+	f(`{"create":{}}`)
+	f(`{"creat":{}}
+{}`)
+	f(`{"create":{}}
+foobar`)
+}
+
+func TestReadBulkRequestSuccess(t *testing.T) {
+	f := func(data, timeField, msgField string, rowsExpected int, timestampsExpected []int64, resultExpected string) {
+		t.Helper()
+
+		var timestamps []int64
+		var result string
+		processLogMessage := func(timestamp int64, fields []logstorage.Field) {
+			timestamps = append(timestamps, timestamp)
+
+			a := make([]string, len(fields))
+			for i, f := range fields {
+				a[i] = fmt.Sprintf("%q:%q", f.Name, f.Value)
+			}
+			s := "{" + strings.Join(a, ",") + "}\n"
+			result += s
+		}
+
+		// Read the request without compression
+		r := bytes.NewBufferString(data)
+		rows, err := readBulkRequest(r, false, timeField, msgField, processLogMessage)
+		if err != nil {
+			t.Fatalf("unexpected error: %s", err)
+		}
+		if rows != rowsExpected {
+			t.Fatalf("unexpected rows read; got %d; want %d", rows, rowsExpected)
+		}
+
+		if !reflect.DeepEqual(timestamps, timestampsExpected) {
+			t.Fatalf("unexpected timestamps;\ngot\n%d\nwant\n%d", timestamps, timestampsExpected)
+		}
+		if result != resultExpected {
+			t.Fatalf("unexpected result;\ngot\n%s\nwant\n%s", result, resultExpected)
+		}
+
+		// Read the request with compression
+		timestamps = nil
+		result = ""
+		compressedData := compressData(data)
+		r = bytes.NewBufferString(compressedData)
+		rows, err = readBulkRequest(r, true, timeField, msgField, processLogMessage)
+		if err != nil {
+			t.Fatalf("unexpected error: %s", err)
+		}
+		if rows != rowsExpected {
+			t.Fatalf("unexpected rows read; got %d; want %d", rows, rowsExpected)
+		}
+
+		if !reflect.DeepEqual(timestamps, timestampsExpected) {
+			t.Fatalf("unexpected timestamps;\ngot\n%d\nwant\n%d", timestamps, timestampsExpected)
+		}
+		if result != resultExpected {
+			t.Fatalf("unexpected result;\ngot\n%s\nwant\n%s", result, resultExpected)
+		}
+	}
+
+	// Verify an empty data
+	f("", "_time", "_msg", 0, nil, "")
+	f("\n", "_time", "_msg", 0, nil, "")
+	f("\n\n", "_time", "_msg", 0, nil, "")
+
+	// Verify non-empty data
+	data := `{"create":{"_index":"filebeat-8.8.0"}}
+{"@timestamp":"2023-06-06T04:48:11.735Z","log":{"offset":71770,"file":{"path":"/var/log/auth.log"}},"message":"foobar"}
+{"create":{"_index":"filebeat-8.8.0"}}
+{"@timestamp":"2023-06-06T04:48:12.735Z","message":"baz"}
+{"index":{"_index":"filebeat-8.8.0"}}
+{"message":"xyz","@timestamp":"2023-06-06T04:48:13.735Z","x":"y"}
+`
+	timeField := "@timestamp"
+	msgField := "message"
+	rowsExpected := 3
+	timestampsExpected := []int64{1686026891735000000, 1686026892735000000, 1686026893735000000}
+	resultExpected := `{"@timestamp":"","log.offset":"71770","log.file.path":"/var/log/auth.log","_msg":"foobar"}
+{"@timestamp":"","_msg":"baz"}
+{"_msg":"xyz","@timestamp":"","x":"y"}
+`
+	f(data, timeField, msgField, rowsExpected, timestampsExpected, resultExpected)
+}
+
+func compressData(s string) string {
+	var bb bytes.Buffer
+	zw := gzip.NewWriter(&bb)
+	if _, err := zw.Write([]byte(s)); err != nil {
+		panic(fmt.Errorf("unexpected error when compressing data: %s", err))
+	}
+	if err := zw.Close(); err != nil {
+		panic(fmt.Errorf("unexpected error when closing gzip writer: %s", err))
+	}
+	return bb.String()
+}

app/vlinsert/elasticsearch/elasticsearch_timing_test.go

@@ -0,0 +1,50 @@
+package elasticsearch
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+)
+
+func BenchmarkReadBulkRequest(b *testing.B) {
+	b.Run("gzip:off", func(b *testing.B) {
+		benchmarkReadBulkRequest(b, false)
+	})
+	b.Run("gzip:on", func(b *testing.B) {
+		benchmarkReadBulkRequest(b, true)
+	})
+}
+
+func benchmarkReadBulkRequest(b *testing.B, isGzip bool) {
+	data := `{"create":{"_index":"filebeat-8.8.0"}}
+{"@timestamp":"2023-06-06T04:48:11.735Z","log":{"offset":71770,"file":{"path":"/var/log/auth.log"}},"message":"foobar"}
+{"create":{"_index":"filebeat-8.8.0"}}
+{"@timestamp":"2023-06-06T04:48:12.735Z","message":"baz"}
+{"create":{"_index":"filebeat-8.8.0"}}
+{"message":"xyz","@timestamp":"2023-06-06T04:48:13.735Z","x":"y"}
+`
+	if isGzip {
+		data = compressData(data)
+	}
+	dataBytes := bytesutil.ToUnsafeBytes(data)
+
+	timeField := "@timestamp"
+	msgField := "message"
+	processLogMessage := func(timestmap int64, fields []logstorage.Field) {}
+
+	b.ReportAllocs()
+	b.SetBytes(int64(len(data)))
+	b.RunParallel(func(pb *testing.PB) {
+		r := &bytes.Reader{}
+		for pb.Next() {
+			r.Reset(dataBytes)
+			_, err := readBulkRequest(r, isGzip, timeField, msgField, processLogMessage)
+			if err != nil {
+				panic(fmt.Errorf("unexpected error: %s", err))
+			}
+		}
+	})
+}

app/vlinsert/insertutils/common_params.go

@@ -0,0 +1,91 @@
+package insertutils
+
+import (
+	"net/http"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httputils"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+// CommonParams contains common HTTP parameters used by log ingestion APIs.
+//
+// See https://docs.victoriametrics.com/VictoriaLogs/data-ingestion/#http-parameters
+type CommonParams struct {
+	TenantID     logstorage.TenantID
+	TimeField    string
+	MsgField     string
+	StreamFields []string
+	IgnoreFields []string
+
+	Debug           bool
+	DebugRequestURI string
+	DebugRemoteAddr string
+}
+
+// GetCommonParams returns CommonParams from r.
+func GetCommonParams(r *http.Request) (*CommonParams, error) {
+	// Extract tenantID
+	tenantID, err := logstorage.GetTenantIDFromRequest(r)
+	if err != nil {
+		return nil, err
+	}
+
+	// Extract time field name from _time_field query arg
+	var timeField = "_time"
+	if tf := r.FormValue("_time_field"); tf != "" {
+		timeField = tf
+	}
+
+	// Extract message field name from _msg_field query arg
+	var msgField = ""
+	if msgf := r.FormValue("_msg_field"); msgf != "" {
+		msgField = msgf
+	}
+
+	streamFields := httputils.GetArray(r, "_stream_fields")
+	ignoreFields := httputils.GetArray(r, "ignore_fields")
+
+	debug := httputils.GetBool(r, "debug")
+	debugRequestURI := ""
+	debugRemoteAddr := ""
+	if debug {
+		debugRequestURI = httpserver.GetRequestURI(r)
+		debugRemoteAddr = httpserver.GetQuotedRemoteAddr(r)
+	}
+
+	cp := &CommonParams{
+		TenantID:        tenantID,
+		TimeField:       timeField,
+		MsgField:        msgField,
+		StreamFields:    streamFields,
+		IgnoreFields:    ignoreFields,
+		Debug:           debug,
+		DebugRequestURI: debugRequestURI,
+		DebugRemoteAddr: debugRemoteAddr,
+	}
+	return cp, nil
+}
+
+// GetProcessLogMessageFunc returns a function, which adds parsed log messages to lr.
+func (cp *CommonParams) GetProcessLogMessageFunc(lr *logstorage.LogRows) func(timestamp int64, fields []logstorage.Field) {
+	return func(timestamp int64, fields []logstorage.Field) {
+		lr.MustAdd(cp.TenantID, timestamp, fields)
+		if cp.Debug {
+			s := lr.GetRowString(0)
+			lr.ResetKeepSettings()
+			logger.Infof("remoteAddr=%s; requestURI=%s; ignoring log entry because of `debug` query arg: %s", cp.DebugRemoteAddr, cp.DebugRequestURI, s)
+			rowsDroppedTotal.Inc()
+			return
+		}
+		if lr.NeedFlush() {
+			vlstorage.MustAddRows(lr)
+			lr.ResetKeepSettings()
+		}
+	}
+}
+
+var rowsDroppedTotal = metrics.NewCounter(`vl_rows_dropped_total{reason="debug"}`)

app/vlinsert/insertutils/flags.go

@@ -0,0 +1,10 @@
+package insertutils
+
+import (
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
+)
+
+var (
+	// MaxLineSizeBytes is the maximum length of a single line for /insert/* handlers
+	MaxLineSizeBytes = flagutil.NewBytes("insert.maxLineSizeBytes", 256*1024, "The maximum size of a single line, which can be read by /insert/* handlers")
+)

app/vlinsert/jsonline/jsonline.go

@@ -0,0 +1,149 @@
+package jsonline
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlinsert/insertutils"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logjson"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/writeconcurrencylimiter"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+// RequestHandler processes jsonline insert requests
+func RequestHandler(w http.ResponseWriter, r *http.Request) bool {
+	w.Header().Add("Content-Type", "application/json")
+
+	if r.Method != "POST" {
+		w.WriteHeader(http.StatusMethodNotAllowed)
+		return true
+	}
+
+	requestsTotal.Inc()
+
+	cp, err := insertutils.GetCommonParams(r)
+	if err != nil {
+		httpserver.Errorf(w, r, "%s", err)
+		return true
+	}
+	lr := logstorage.GetLogRows(cp.StreamFields, cp.IgnoreFields)
+	processLogMessage := cp.GetProcessLogMessageFunc(lr)
+
+	reader := r.Body
+	if r.Header.Get("Content-Encoding") == "gzip" {
+		zr, err := common.GetGzipReader(reader)
+		if err != nil {
+			logger.Errorf("cannot read gzipped _bulk request: %s", err)
+			return true
+		}
+		defer common.PutGzipReader(zr)
+		reader = zr
+	}
+
+	wcr := writeconcurrencylimiter.GetReader(reader)
+	defer writeconcurrencylimiter.PutReader(wcr)
+
+	lb := lineBufferPool.Get()
+	defer lineBufferPool.Put(lb)
+
+	lb.B = bytesutil.ResizeNoCopyNoOverallocate(lb.B, insertutils.MaxLineSizeBytes.IntN())
+	sc := bufio.NewScanner(wcr)
+	sc.Buffer(lb.B, len(lb.B))
+
+	n := 0
+	for {
+		ok, err := readLine(sc, cp.TimeField, cp.MsgField, processLogMessage)
+		wcr.DecConcurrency()
+		if err != nil {
+			logger.Errorf("cannot read line #%d in /jsonline request: %s", n, err)
+			break
+		}
+		if !ok {
+			break
+		}
+		n++
+		rowsIngestedTotal.Inc()
+	}
+
+	vlstorage.MustAddRows(lr)
+	logstorage.PutLogRows(lr)
+
+	return true
+}
+
+func readLine(sc *bufio.Scanner, timeField, msgField string, processLogMessage func(timestamp int64, fields []logstorage.Field)) (bool, error) {
+	var line []byte
+	for len(line) == 0 {
+		if !sc.Scan() {
+			if err := sc.Err(); err != nil {
+				if errors.Is(err, bufio.ErrTooLong) {
+					return false, fmt.Errorf(`cannot read json line, since its size exceeds -insert.maxLineSizeBytes=%d`, insertutils.MaxLineSizeBytes.IntN())
+				}
+				return false, err
+			}
+			return false, nil
+		}
+		line = sc.Bytes()
+	}
+
+	p := logjson.GetParser()
+	if err := p.ParseLogMessage(line); err != nil {
+		return false, fmt.Errorf("cannot parse json-encoded log entry: %w", err)
+	}
+	ts, err := extractTimestampFromFields(timeField, p.Fields)
+	if err != nil {
+		return false, fmt.Errorf("cannot parse timestamp: %w", err)
+	}
+	if ts == 0 {
+		ts = time.Now().UnixNano()
+	}
+	p.RenameField(msgField, "_msg")
+	processLogMessage(ts, p.Fields)
+	logjson.PutParser(p)
+	return true, nil
+}
+
+func extractTimestampFromFields(timeField string, fields []logstorage.Field) (int64, error) {
+	for i := range fields {
+		f := &fields[i]
+		if f.Name != timeField {
+			continue
+		}
+		timestamp, err := parseISO8601Timestamp(f.Value)
+		if err != nil {
+			return 0, err
+		}
+		f.Value = ""
+		return timestamp, nil
+	}
+	return 0, nil
+}
+
+func parseISO8601Timestamp(s string) (int64, error) {
+	if s == "0" || s == "" {
+		// Special case for returning the current timestamp.
+		// It must be automatically converted to the current timestamp by the caller.
+		return 0, nil
+	}
+	t, err := time.Parse(time.RFC3339, s)
+	if err != nil {
+		return 0, fmt.Errorf("cannot parse timestamp %q: %w", s, err)
+	}
+	return t.UnixNano(), nil
+}
+
+var lineBufferPool bytesutil.ByteBufferPool
+
+var (
+	requestsTotal     = metrics.NewCounter(`vl_http_requests_total{path="/insert/jsonline"}`)
+	rowsIngestedTotal = metrics.NewCounter(`vl_rows_ingested_total{type="jsonline"}`)
+)

app/vlinsert/jsonline/jsonline_test.go

@@ -0,0 +1,70 @@
+package jsonline
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func TestReadBulkRequestSuccess(t *testing.T) {
+	f := func(data, timeField, msgField string, rowsExpected int, timestampsExpected []int64, resultExpected string) {
+		t.Helper()
+
+		var timestamps []int64
+		var result string
+		processLogMessage := func(timestamp int64, fields []logstorage.Field) {
+			timestamps = append(timestamps, timestamp)
+
+			a := make([]string, len(fields))
+			for i, f := range fields {
+				a[i] = fmt.Sprintf("%q:%q", f.Name, f.Value)
+			}
+			s := "{" + strings.Join(a, ",") + "}\n"
+			result += s
+		}
+
+		// Read the request without compression
+		r := bytes.NewBufferString(data)
+		sc := bufio.NewScanner(r)
+		rows := 0
+		for {
+			ok, err := readLine(sc, timeField, msgField, processLogMessage)
+			if err != nil {
+				t.Fatalf("unexpected error: %s", err)
+			}
+			if !ok {
+				break
+			}
+			rows++
+		}
+		if rows != rowsExpected {
+			t.Fatalf("unexpected rows read; got %d; want %d", rows, rowsExpected)
+		}
+
+		if !reflect.DeepEqual(timestamps, timestampsExpected) {
+			t.Fatalf("unexpected timestamps;\ngot\n%d\nwant\n%d", timestamps, timestampsExpected)
+		}
+		if result != resultExpected {
+			t.Fatalf("unexpected result;\ngot\n%s\nwant\n%s", result, resultExpected)
+		}
+	}
+
+	// Verify non-empty data
+	data := `{"@timestamp":"2023-06-06T04:48:11.735Z","log":{"offset":71770,"file":{"path":"/var/log/auth.log"}},"message":"foobar"}
+{"@timestamp":"2023-06-06T04:48:12.735Z","message":"baz"}
+{"message":"xyz","@timestamp":"2023-06-06T04:48:13.735Z","x":"y"}
+`
+	timeField := "@timestamp"
+	msgField := "message"
+	rowsExpected := 3
+	timestampsExpected := []int64{1686026891735000000, 1686026892735000000, 1686026893735000000}
+	resultExpected := `{"@timestamp":"","log.offset":"71770","log.file.path":"/var/log/auth.log","_msg":"foobar"}
+{"@timestamp":"","_msg":"baz"}
+{"_msg":"xyz","@timestamp":"","x":"y"}
+`
+	f(data, timeField, msgField, rowsExpected, timestampsExpected, resultExpected)
+}

app/vlinsert/loki/loki.go

@@ -0,0 +1,56 @@
+package loki
+
+import (
+	"net/http"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlinsert/insertutils"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+var (
+	lokiRequestsJSONTotal     = metrics.NewCounter(`vl_http_requests_total{path="/insert/loki/api/v1/push",format="json"}`)
+	lokiRequestsProtobufTotal = metrics.NewCounter(`vl_http_requests_total{path="/insert/loki/api/v1/push",format="protobuf"}`)
+)
+
+// RequestHandler processes Loki insert requests
+//
+// See https://grafana.com/docs/loki/latest/api/#push-log-entries-to-loki
+func RequestHandler(path string, w http.ResponseWriter, r *http.Request) bool {
+	if path != "/api/v1/push" {
+		return false
+	}
+	contentType := r.Header.Get("Content-Type")
+	switch contentType {
+	case "application/json":
+		lokiRequestsJSONTotal.Inc()
+		return handleJSON(r, w)
+	default:
+		// Protobuf request body should be handled by default accoring to https://grafana.com/docs/loki/latest/api/#push-log-entries-to-loki
+		lokiRequestsProtobufTotal.Inc()
+		return handleProtobuf(r, w)
+	}
+}
+
+func getCommonParams(r *http.Request) (*insertutils.CommonParams, error) {
+	cp, err := insertutils.GetCommonParams(r)
+	if err != nil {
+		return nil, err
+	}
+
+	// If parsed tenant is (0,0) it is likely to be default tenant
+	// Try parsing tenant from Loki headers
+	if cp.TenantID.AccountID == 0 && cp.TenantID.ProjectID == 0 {
+		org := r.Header.Get("X-Scope-OrgID")
+		if org != "" {
+			tenantID, err := logstorage.GetTenantIDFromString(org)
+			if err != nil {
+				return nil, err
+			}
+			cp.TenantID = tenantID
+		}
+
+	}
+
+	return cp, nil
+}

app/vlinsert/loki/loki_json.go

@@ -0,0 +1,190 @@
+package loki
+
+import (
+	"fmt"
+	"io"
+	"math"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/writeconcurrencylimiter"
+	"github.com/VictoriaMetrics/metrics"
+	"github.com/valyala/fastjson"
+)
+
+var (
+	rowsIngestedJSONTotal = metrics.NewCounter(`vl_rows_ingested_total{type="loki",format="json"}`)
+	parserPool            fastjson.ParserPool
+)
+
+func handleJSON(r *http.Request, w http.ResponseWriter) bool {
+	reader := r.Body
+	if r.Header.Get("Content-Encoding") == "gzip" {
+		zr, err := common.GetGzipReader(reader)
+		if err != nil {
+			httpserver.Errorf(w, r, "cannot initialize gzip reader: %s", err)
+			return true
+		}
+		defer common.PutGzipReader(zr)
+		reader = zr
+	}
+
+	wcr := writeconcurrencylimiter.GetReader(reader)
+	data, err := io.ReadAll(wcr)
+	writeconcurrencylimiter.PutReader(wcr)
+	if err != nil {
+		httpserver.Errorf(w, r, "cannot read request body: %s", err)
+		return true
+	}
+
+	cp, err := getCommonParams(r)
+	if err != nil {
+		httpserver.Errorf(w, r, "cannot parse common params from request: %s", err)
+		return true
+	}
+	lr := logstorage.GetLogRows(cp.StreamFields, cp.IgnoreFields)
+	processLogMessage := cp.GetProcessLogMessageFunc(lr)
+	n, err := parseJSONRequest(data, processLogMessage)
+	vlstorage.MustAddRows(lr)
+	logstorage.PutLogRows(lr)
+	if err != nil {
+		httpserver.Errorf(w, r, "cannot parse Loki request: %s", err)
+		return true
+	}
+	rowsIngestedJSONTotal.Add(n)
+	return true
+}
+
+func parseJSONRequest(data []byte, processLogMessage func(timestamp int64, fields []logstorage.Field)) (int, error) {
+	p := parserPool.Get()
+	defer parserPool.Put(p)
+	v, err := p.ParseBytes(data)
+	if err != nil {
+		return 0, fmt.Errorf("cannot parse JSON request body: %w", err)
+	}
+
+	streamsV := v.Get("streams")
+	if streamsV == nil {
+		return 0, fmt.Errorf("missing `streams` item in the parsed JSON: %q", v)
+	}
+	streams, err := streamsV.Array()
+	if err != nil {
+		return 0, fmt.Errorf("`streams` item in the parsed JSON must contain an array; got %q", streamsV)
+	}
+
+	currentTimestamp := time.Now().UnixNano()
+	var commonFields []logstorage.Field
+	rowsIngested := 0
+	for _, stream := range streams {
+		// populate common labels from `stream` dict
+		commonFields = commonFields[:0]
+		labelsV := stream.Get("stream")
+		var labels *fastjson.Object
+		if labelsV != nil {
+			o, err := labelsV.Object()
+			if err != nil {
+				return rowsIngested, fmt.Errorf("`stream` item in the parsed JSON must contain an object; got %q", labelsV)
+			}
+			labels = o
+		}
+		labels.Visit(func(k []byte, v *fastjson.Value) {
+			if err != nil {
+				return
+			}
+			vStr, errLocal := v.StringBytes()
+			if errLocal != nil {
+				err = fmt.Errorf("unexpected label value type for %q:%q; want string", k, v)
+				return
+			}
+			commonFields = append(commonFields, logstorage.Field{
+				Name:  bytesutil.ToUnsafeString(k),
+				Value: bytesutil.ToUnsafeString(vStr),
+			})
+		})
+		if err != nil {
+			return rowsIngested, fmt.Errorf("error when parsing `stream` object: %w", err)
+		}
+
+		// populate messages from `values` array
+		linesV := stream.Get("values")
+		if linesV == nil {
+			return rowsIngested, fmt.Errorf("missing `values` item in the parsed JSON %q", stream)
+		}
+		lines, err := linesV.Array()
+		if err != nil {
+			return rowsIngested, fmt.Errorf("`values` item in the parsed JSON must contain an array; got %q", linesV)
+		}
+
+		fields := commonFields
+		for _, line := range lines {
+			lineA, err := line.Array()
+			if err != nil {
+				return rowsIngested, fmt.Errorf("unexpected contents of `values` item; want array; got %q", line)
+			}
+			if len(lineA) != 2 {
+				return rowsIngested, fmt.Errorf("unexpected number of values in `values` item array %q; got %d want 2", line, len(lineA))
+			}
+
+			// parse timestamp
+			timestamp, err := lineA[0].StringBytes()
+			if err != nil {
+				return rowsIngested, fmt.Errorf("unexpected log timestamp type for %q; want string", lineA[0])
+			}
+			ts, err := parseLokiTimestamp(bytesutil.ToUnsafeString(timestamp))
+			if err != nil {
+				return rowsIngested, fmt.Errorf("cannot parse log timestamp %q: %w", timestamp, err)
+			}
+			if ts == 0 {
+				ts = currentTimestamp
+			}
+
+			// parse log message
+			msg, err := lineA[1].StringBytes()
+			if err != nil {
+				return rowsIngested, fmt.Errorf("unexpected log message type for %q; want string", lineA[1])
+			}
+
+			fields = append(fields[:len(commonFields)], logstorage.Field{
+				Name:  "_msg",
+				Value: bytesutil.ToUnsafeString(msg),
+			})
+			processLogMessage(ts, fields)
+
+		}
+		rowsIngested += len(lines)
+	}
+
+	return rowsIngested, nil
+}
+
+func parseLokiTimestamp(s string) (int64, error) {
+	if s == "" {
+		// Special case - an empty timestamp must be substituted with the current time by the caller.
+		return 0, nil
+	}
+	n, err := strconv.ParseInt(s, 10, 64)
+	if err != nil {
+		// Fall back to parsing floating-point value
+		f, err := strconv.ParseFloat(s, 64)
+		if err != nil {
+			return 0, err
+		}
+		if f > math.MaxInt64 {
+			return 0, fmt.Errorf("too big timestamp in nanoseconds: %v; mustn't exceed %v", f, int64(math.MaxInt64))
+		}
+		if f < math.MinInt64 {
+			return 0, fmt.Errorf("too small timestamp in nanoseconds: %v; must be bigger or equal to %v", f, int64(math.MinInt64))
+		}
+		n = int64(f)
+	}
+	if n < 0 {
+		return 0, fmt.Errorf("too small timestamp in nanoseconds: %d; must be bigger than 0", n)
+	}
+	return n, nil
+}

app/vlinsert/loki/loki_json_test.go

@@ -0,0 +1,130 @@
+package loki
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+)
+
+func TestParseJSONRequestFailure(t *testing.T) {
+	f := func(s string) {
+		t.Helper()
+		n, err := parseJSONRequest([]byte(s), func(timestamp int64, fields []logstorage.Field) {
+			t.Fatalf("unexpected call to parseJSONRequest callback!")
+		})
+		if err == nil {
+			t.Fatalf("expecting non-nil error")
+		}
+		if n != 0 {
+			t.Fatalf("unexpected number of parsed lines: %d; want 0", n)
+		}
+	}
+	f(``)
+
+	// Invalid json
+	f(`{}`)
+	f(`[]`)
+	f(`"foo"`)
+	f(`123`)
+
+	// invalid type for `streams` item
+	f(`{"streams":123}`)
+
+	// Missing `values` item
+	f(`{"streams":[{}]}`)
+
+	// Invalid type for `values` item
+	f(`{"streams":[{"values":"foobar"}]}`)
+
+	// Invalid type for `stream` item
+	f(`{"streams":[{"stream":[],"values":[]}]}`)
+
+	// Invalid type for `values` individual item
+	f(`{"streams":[{"values":[123]}]}`)
+
+	// Invalid length of `values` individual item
+	f(`{"streams":[{"values":[[]]}]}`)
+	f(`{"streams":[{"values":[["123"]]}]}`)
+	f(`{"streams":[{"values":[["123","456","789"]]}]}`)
+
+	// Invalid type for timestamp inside `values` individual item
+	f(`{"streams":[{"values":[[123,"456"]}]}`)
+
+	// Invalid type for log message
+	f(`{"streams":[{"values":[["123",1234]]}]}`)
+}
+
+func TestParseJSONRequestSuccess(t *testing.T) {
+	f := func(s string, resultExpected string) {
+		t.Helper()
+		var lines []string
+		n, err := parseJSONRequest([]byte(s), func(timestamp int64, fields []logstorage.Field) {
+			var a []string
+			for _, f := range fields {
+				a = append(a, f.String())
+			}
+			line := fmt.Sprintf("_time:%d %s", timestamp, strings.Join(a, " "))
+			lines = append(lines, line)
+		})
+		if err != nil {
+			t.Fatalf("unexpected error: %s", err)
+		}
+		if n != len(lines) {
+			t.Fatalf("unexpected number of lines parsed; got %d; want %d", n, len(lines))
+		}
+		result := strings.Join(lines, "\n")
+		if result != resultExpected {
+			t.Fatalf("unexpected result;\ngot\n%s\nwant\n%s", result, resultExpected)
+		}
+	}
+
+	// Empty streams
+	f(`{"streams":[]}`, ``)
+	f(`{"streams":[{"values":[]}]}`, ``)
+	f(`{"streams":[{"stream":{},"values":[]}]}`, ``)
+	f(`{"streams":[{"stream":{"foo":"bar"},"values":[]}]}`, ``)
+
+	// Empty stream labels
+	f(`{"streams":[{"values":[["1577836800000000001", "foo bar"]]}]}`, `_time:1577836800000000001 "_msg":"foo bar"`)
+	f(`{"streams":[{"stream":{},"values":[["1577836800000000001", "foo bar"]]}]}`, `_time:1577836800000000001 "_msg":"foo bar"`)
+
+	// Non-empty stream labels
+	f(`{"streams":[{"stream":{
+	"label1": "value1",
+	"label2": "value2"
+},"values":[
+	["1577836800000000001", "foo bar"],
+	["1477836900005000002", "abc"],
+	["147.78369e9", "foobar"]
+]}]}`, `_time:1577836800000000001 "label1":"value1" "label2":"value2" "_msg":"foo bar"
+_time:1477836900005000002 "label1":"value1" "label2":"value2" "_msg":"abc"
+_time:147783690000 "label1":"value1" "label2":"value2" "_msg":"foobar"`)
+
+	// Multiple streams
+	f(`{
+	"streams": [
+		{
+			"stream": {
+				"foo": "bar",
+				"a": "b"
+			},
+			"values": [
+				["1577836800000000001", "foo bar"],
+				["1577836900005000002", "abc"]
+			]
+		},
+		{
+			"stream": {
+				"x": "y"
+			},
+			"values": [
+				["1877836900005000002", "yx"]
+			]
+		}
+	]
+}`, `_time:1577836800000000001 "foo":"bar" "a":"b" "_msg":"foo bar"
+_time:1577836900005000002 "foo":"bar" "a":"b" "_msg":"abc"
+_time:1877836900005000002 "x":"y" "_msg":"yx"`)
+}

app/vlinsert/loki/loki_json_timing_test.go

@@ -0,0 +1,78 @@
+package loki
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+)
+
+func BenchmarkParseJSONRequest(b *testing.B) {
+	for _, streams := range []int{5, 10} {
+		for _, rows := range []int{100, 1000} {
+			for _, labels := range []int{10, 50} {
+				b.Run(fmt.Sprintf("streams_%d/rows_%d/labels_%d", streams, rows, labels), func(b *testing.B) {
+					benchmarkParseJSONRequest(b, streams, rows, labels)
+				})
+			}
+		}
+	}
+}
+
+func benchmarkParseJSONRequest(b *testing.B, streams, rows, labels int) {
+	b.ReportAllocs()
+	b.SetBytes(int64(streams * rows))
+	b.RunParallel(func(pb *testing.PB) {
+		data := getJSONBody(streams, rows, labels)
+		for pb.Next() {
+			_, err := parseJSONRequest(data, func(timestamp int64, fields []logstorage.Field) {})
+			if err != nil {
+				panic(fmt.Errorf("unexpected error: %s", err))
+			}
+		}
+	})
+}
+
+func getJSONBody(streams, rows, labels int) []byte {
+	body := append([]byte{}, `{"streams":[`...)
+	now := time.Now().UnixNano()
+	valuePrefix := fmt.Sprintf(`["%d","value_`, now)
+
+	for i := 0; i < streams; i++ {
+		body = append(body, `{"stream":{`...)
+
+		for j := 0; j < labels; j++ {
+			body = append(body, `"label_`...)
+			body = strconv.AppendInt(body, int64(j), 10)
+			body = append(body, `":"value_`...)
+			body = strconv.AppendInt(body, int64(j), 10)
+			body = append(body, '"')
+			if j < labels-1 {
+				body = append(body, ',')
+			}
+
+		}
+		body = append(body, `}, "values":[`...)
+
+		for j := 0; j < rows; j++ {
+			body = append(body, valuePrefix...)
+			body = strconv.AppendInt(body, int64(j), 10)
+			body = append(body, `"]`...)
+			if j < rows-1 {
+				body = append(body, ',')
+			}
+		}
+
+		body = append(body, `]}`...)
+		if i < streams-1 {
+			body = append(body, ',')
+		}
+
+	}
+
+	body = append(body, `]}`...)
+
+	return body
+}

app/vlinsert/loki/loki_protobuf.go

@@ -0,0 +1,171 @@
+package loki
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/writeconcurrencylimiter"
+	"github.com/VictoriaMetrics/metrics"
+	"github.com/golang/snappy"
+)
+
+var (
+	rowsIngestedProtobufTotal = metrics.NewCounter(`vl_rows_ingested_total{type="loki",format="protobuf"}`)
+	bytesBufPool              bytesutil.ByteBufferPool
+	pushReqsPool              sync.Pool
+)
+
+func handleProtobuf(r *http.Request, w http.ResponseWriter) bool {
+	wcr := writeconcurrencylimiter.GetReader(r.Body)
+	data, err := io.ReadAll(wcr)
+	writeconcurrencylimiter.PutReader(wcr)
+	if err != nil {
+		httpserver.Errorf(w, r, "cannot read request body: %s", err)
+		return true
+	}
+
+	cp, err := getCommonParams(r)
+	if err != nil {
+		httpserver.Errorf(w, r, "cannot parse common params from request: %s", err)
+		return true
+	}
+	lr := logstorage.GetLogRows(cp.StreamFields, cp.IgnoreFields)
+	processLogMessage := cp.GetProcessLogMessageFunc(lr)
+	n, err := parseProtobufRequest(data, processLogMessage)
+	vlstorage.MustAddRows(lr)
+	logstorage.PutLogRows(lr)
+	if err != nil {
+		httpserver.Errorf(w, r, "cannot parse loki request: %s", err)
+		return true
+	}
+	rowsIngestedProtobufTotal.Add(n)
+	return true
+}
+
+func parseProtobufRequest(data []byte, processLogMessage func(timestamp int64, fields []logstorage.Field)) (int, error) {
+	bb := bytesBufPool.Get()
+	defer bytesBufPool.Put(bb)
+
+	buf, err := snappy.Decode(bb.B[:cap(bb.B)], data)
+	if err != nil {
+		return 0, fmt.Errorf("cannot decode snappy-encoded request body: %w", err)
+	}
+	bb.B = buf
+
+	req := getPushRequest()
+	defer putPushRequest(req)
+
+	err = req.Unmarshal(bb.B)
+	if err != nil {
+		return 0, fmt.Errorf("cannot parse request body: %s", err)
+	}
+
+	var commonFields []logstorage.Field
+	rowsIngested := 0
+	streams := req.Streams
+	currentTimestamp := time.Now().UnixNano()
+	for i := range streams {
+		stream := &streams[i]
+		// st.Labels contains labels for the stream.
+		// Labels are same for all entries in the stream.
+		commonFields, err = parsePromLabels(commonFields[:0], stream.Labels)
+		if err != nil {
+			return rowsIngested, fmt.Errorf("cannot parse stream labels %q: %s", stream.Labels, err)
+		}
+		fields := commonFields
+
+		entries := stream.Entries
+		for j := range entries {
+			entry := &entries[j]
+			fields = append(fields[:len(commonFields)], logstorage.Field{
+				Name:  "_msg",
+				Value: entry.Line,
+			})
+			ts := entry.Timestamp.UnixNano()
+			if ts == 0 {
+				ts = currentTimestamp
+			}
+			processLogMessage(ts, fields)
+		}
+		rowsIngested += len(stream.Entries)
+	}
+	return rowsIngested, nil
+}
+
+// parsePromLabels parses log fields in Prometheus text exposition format from s, appends them to dst and returns the result.
+//
+// See test data of promtail for examples: https://github.com/grafana/loki/blob/a24ef7b206e0ca63ee74ca6ecb0a09b745cd2258/pkg/push/types_test.go
+func parsePromLabels(dst []logstorage.Field, s string) ([]logstorage.Field, error) {
+	// Make sure s is wrapped into `{...}`
+	s = strings.TrimSpace(s)
+	if len(s) < 2 {
+		return nil, fmt.Errorf("too short string to parse: %q", s)
+	}
+	if s[0] != '{' {
+		return nil, fmt.Errorf("missing `{` at the beginning of %q", s)
+	}
+	if s[len(s)-1] != '}' {
+		return nil, fmt.Errorf("missing `}` at the end of %q", s)
+	}
+	s = s[1 : len(s)-1]
+
+	for len(s) > 0 {
+		// Parse label name
+		n := strings.IndexByte(s, '=')
+		if n < 0 {
+			return nil, fmt.Errorf("cannot find `=` char for label value at %s", s)
+		}
+		name := s[:n]
+		s = s[n+1:]
+
+		// Parse label value
+		qs, err := strconv.QuotedPrefix(s)
+		if err != nil {
+			return nil, fmt.Errorf("cannot parse value for label %q at %s: %w", name, s, err)
+		}
+		s = s[len(qs):]
+		value, err := strconv.Unquote(qs)
+		if err != nil {
+			return nil, fmt.Errorf("cannot unquote value %q for label %q: %w", qs, name, err)
+		}
+
+		// Append the found field to dst.
+		dst = append(dst, logstorage.Field{
+			Name:  name,
+			Value: value,
+		})
+
+		// Check whether there are other labels remaining
+		if len(s) == 0 {
+			break
+		}
+		if !strings.HasPrefix(s, ",") {
+			return nil, fmt.Errorf("missing `,` char at %s", s)
+		}
+		s = s[1:]
+		s = strings.TrimPrefix(s, " ")
+	}
+	return dst, nil
+}
+
+func getPushRequest() *PushRequest {
+	v := pushReqsPool.Get()
+	if v == nil {
+		return &PushRequest{}
+	}
+	return v.(*PushRequest)
+}
+
+func putPushRequest(req *PushRequest) {
+	req.Reset()
+	pushReqsPool.Put(req)
+}

app/vlinsert/loki/loki_protobuf_test.go

@@ -0,0 +1,171 @@
+package loki
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"github.com/golang/snappy"
+)
+
+func TestParseProtobufRequestSuccess(t *testing.T) {
+	f := func(s string, resultExpected string) {
+		t.Helper()
+		var pr PushRequest
+		n, err := parseJSONRequest([]byte(s), func(timestamp int64, fields []logstorage.Field) {
+			msg := ""
+			for _, f := range fields {
+				if f.Name == "_msg" {
+					msg = f.Value
+				}
+			}
+			var a []string
+			for _, f := range fields {
+				if f.Name == "_msg" {
+					continue
+				}
+				item := fmt.Sprintf("%s=%q", f.Name, f.Value)
+				a = append(a, item)
+			}
+			labels := "{" + strings.Join(a, ", ") + "}"
+			pr.Streams = append(pr.Streams, Stream{
+				Labels: labels,
+				Entries: []Entry{
+					{
+						Timestamp: time.Unix(0, timestamp),
+						Line:      msg,
+					},
+				},
+			})
+		})
+		if err != nil {
+			t.Fatalf("unexpected error: %s", err)
+		}
+		if n != len(pr.Streams) {
+			t.Fatalf("unexpected number of streams; got %d; want %d", len(pr.Streams), n)
+		}
+
+		data, err := pr.Marshal()
+		if err != nil {
+			t.Fatalf("unexpected error when marshaling PushRequest: %s", err)
+		}
+		encodedData := snappy.Encode(nil, data)
+
+		var lines []string
+		n, err = parseProtobufRequest(encodedData, func(timestamp int64, fields []logstorage.Field) {
+			var a []string
+			for _, f := range fields {
+				a = append(a, f.String())
+			}
+			line := fmt.Sprintf("_time:%d %s", timestamp, strings.Join(a, " "))
+			lines = append(lines, line)
+		})
+		if err != nil {
+			t.Fatalf("unexpected error: %s", err)
+		}
+		if n != len(lines) {
+			t.Fatalf("unexpected number of lines parsed; got %d; want %d", n, len(lines))
+		}
+		result := strings.Join(lines, "\n")
+		if result != resultExpected {
+			t.Fatalf("unexpected result;\ngot\n%s\nwant\n%s", result, resultExpected)
+		}
+	}
+
+	// Empty streams
+	f(`{"streams":[]}`, ``)
+	f(`{"streams":[{"values":[]}]}`, ``)
+	f(`{"streams":[{"stream":{},"values":[]}]}`, ``)
+	f(`{"streams":[{"stream":{"foo":"bar"},"values":[]}]}`, ``)
+
+	// Empty stream labels
+	f(`{"streams":[{"values":[["1577836800000000001", "foo bar"]]}]}`, `_time:1577836800000000001 "_msg":"foo bar"`)
+	f(`{"streams":[{"stream":{},"values":[["1577836800000000001", "foo bar"]]}]}`, `_time:1577836800000000001 "_msg":"foo bar"`)
+
+	// Non-empty stream labels
+	f(`{"streams":[{"stream":{
+	"label1": "value1",
+	"label2": "value2"
+},"values":[
+	["1577836800000000001", "foo bar"],
+	["1477836900005000002", "abc"],
+	["147.78369e9", "foobar"]
+]}]}`, `_time:1577836800000000001 "label1":"value1" "label2":"value2" "_msg":"foo bar"
+_time:1477836900005000002 "label1":"value1" "label2":"value2" "_msg":"abc"
+_time:147783690000 "label1":"value1" "label2":"value2" "_msg":"foobar"`)
+
+	// Multiple streams
+	f(`{
+	"streams": [
+		{
+			"stream": {
+				"foo": "bar",
+				"a": "b"
+			},
+			"values": [
+				["1577836800000000001", "foo bar"],
+				["1577836900005000002", "abc"]
+			]
+		},
+		{
+			"stream": {
+				"x": "y"
+			},
+			"values": [
+				["1877836900005000002", "yx"]
+			]
+		}
+	]
+}`, `_time:1577836800000000001 "foo":"bar" "a":"b" "_msg":"foo bar"
+_time:1577836900005000002 "foo":"bar" "a":"b" "_msg":"abc"
+_time:1877836900005000002 "x":"y" "_msg":"yx"`)
+}
+
+func TestParsePromLabelsSuccess(t *testing.T) {
+	f := func(s string) {
+		t.Helper()
+		fields, err := parsePromLabels(nil, s)
+		if err != nil {
+			t.Fatalf("unexpected error: %s", err)
+		}
+
+		var a []string
+		for _, f := range fields {
+			a = append(a, fmt.Sprintf("%s=%q", f.Name, f.Value))
+		}
+		result := "{" + strings.Join(a, ", ") + "}"
+		if result != s {
+			t.Fatalf("unexpected result;\ngot\n%s\nwant\n%s", result, s)
+		}
+	}
+
+	f("{}")
+	f(`{foo="bar"}`)
+	f(`{foo="bar", baz="x", y="z"}`)
+	f(`{foo="ba\"r\\z\n", a="", b="\"\\"}`)
+}
+
+func TestParsePromLabelsFailure(t *testing.T) {
+	f := func(s string) {
+		t.Helper()
+		fields, err := parsePromLabels(nil, s)
+		if err == nil {
+			t.Fatalf("expecting non-nil error")
+		}
+		if len(fields) > 0 {
+			t.Fatalf("unexpected non-empty fields: %s", fields)
+		}
+	}
+
+	f("")
+	f("{")
+	f(`{foo}`)
+	f(`{foo=bar}`)
+	f(`{foo="bar}`)
+	f(`{foo="ba\",r}`)
+	f(`{foo="bar" baz="aa"}`)
+	f(`foobar`)
+	f(`foo{bar="baz"}`)
+}

app/vlinsert/loki/loki_protobuf_timing_test.go

@@ -0,0 +1,65 @@
+package loki
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"github.com/golang/snappy"
+)
+
+func BenchmarkParseProtobufRequest(b *testing.B) {
+	for _, streams := range []int{5, 10} {
+		for _, rows := range []int{100, 1000} {
+			for _, labels := range []int{10, 50} {
+				b.Run(fmt.Sprintf("streams_%d/rows_%d/labels_%d", streams, rows, labels), func(b *testing.B) {
+					benchmarkParseProtobufRequest(b, streams, rows, labels)
+				})
+			}
+		}
+	}
+}
+
+func benchmarkParseProtobufRequest(b *testing.B, streams, rows, labels int) {
+	b.ReportAllocs()
+	b.SetBytes(int64(streams * rows))
+	b.RunParallel(func(pb *testing.PB) {
+		body := getProtobufBody(streams, rows, labels)
+		for pb.Next() {
+			_, err := parseProtobufRequest(body, func(timestamp int64, fields []logstorage.Field) {})
+			if err != nil {
+				panic(fmt.Errorf("unexpected error: %s", err))
+			}
+		}
+	})
+}
+
+func getProtobufBody(streams, rows, labels int) []byte {
+	var pr PushRequest
+
+	for i := 0; i < streams; i++ {
+		var st Stream
+
+		st.Labels = `{`
+		for j := 0; j < labels; j++ {
+			st.Labels += `label_` + strconv.Itoa(j) + `="value_` + strconv.Itoa(j) + `"`
+			if j < labels-1 {
+				st.Labels += `,`
+			}
+		}
+		st.Labels += `}`
+
+		for j := 0; j < rows; j++ {
+			st.Entries = append(st.Entries, Entry{Timestamp: time.Now(), Line: "value_" + strconv.Itoa(j)})
+		}
+
+		pr.Streams = append(pr.Streams, st)
+	}
+
+	body, _ := pr.Marshal()
+	encodedBody := snappy.Encode(nil, body)
+
+	return encodedBody
+}

app/vlinsert/loki/push_request.proto

@@ -0,0 +1,38 @@
+syntax = "proto3";
+
+// source: https://raw.githubusercontent.com/grafana/loki/main/pkg/push/push.proto
+// Licensed under the Apache License, Version 2.0 (the "License");
+// https://github.com/grafana/loki/blob/main/pkg/push/LICENSE
+
+package logproto;
+
+import "gogoproto/gogo.proto";
+import "google/protobuf/timestamp.proto";
+
+option go_package = "github.com/VictoriaMetrics/VictoriaMetrics/app/vlinsert/loki";
+
+message PushRequest {
+  repeated StreamAdapter streams = 1 [
+    (gogoproto.jsontag) = "streams",
+    (gogoproto.customtype) = "Stream"
+  ];
+}
+
+message StreamAdapter {
+  string labels = 1 [(gogoproto.jsontag) = "labels"];
+  repeated EntryAdapter entries = 2 [
+    (gogoproto.nullable) = false,
+    (gogoproto.jsontag) = "entries"
+  ];
+  // hash contains the original hash of the stream.
+  uint64 hash = 3 [(gogoproto.jsontag) = "-"];
+}
+
+message EntryAdapter {
+  google.protobuf.Timestamp timestamp = 1 [
+    (gogoproto.stdtime) = true,
+    (gogoproto.nullable) = false,
+    (gogoproto.jsontag) = "ts"
+  ];
+  string line = 2 [(gogoproto.jsontag) = "line"];
+}

app/vlinsert/loki/timestamp.go

@@ -0,0 +1,110 @@
+package loki
+
+// source: https://raw.githubusercontent.com/grafana/loki/main/pkg/push/timestamp.go
+// Licensed under the Apache License, Version 2.0 (the "License");
+// https://github.com/grafana/loki/blob/main/pkg/push/LICENSE
+
+import (
+	"errors"
+	"strconv"
+	"time"
+
+	"github.com/gogo/protobuf/types"
+)
+
+const (
+	// Seconds field of the earliest valid Timestamp.
+	// This is time.Date(1, 1, 1, 0, 0, 0, 0, time.UTC).Unix().
+	minValidSeconds = -62135596800
+	// Seconds field just after the latest valid Timestamp.
+	// This is time.Date(10000, 1, 1, 0, 0, 0, 0, time.UTC).Unix().
+	maxValidSeconds = 253402300800
+)
+
+// validateTimestamp determines whether a Timestamp is valid.
+// A valid timestamp represents a time in the range
+// [0001-01-01, 10000-01-01) and has a Nanos field
+// in the range [0, 1e9).
+//
+// If the Timestamp is valid, validateTimestamp returns nil.
+// Otherwise, it returns an error that describes
+// the problem.
+//
+// Every valid Timestamp can be represented by a time.Time, but the converse is not true.
+func validateTimestamp(ts *types.Timestamp) error {
+	if ts == nil {
+		return errors.New("timestamp: nil Timestamp")
+	}
+	if ts.Seconds < minValidSeconds {
+		return errors.New("timestamp: " + formatTimestamp(ts) + " before 0001-01-01")
+	}
+	if ts.Seconds >= maxValidSeconds {
+		return errors.New("timestamp: " + formatTimestamp(ts) + " after 10000-01-01")
+	}
+	if ts.Nanos < 0 || ts.Nanos >= 1e9 {
+		return errors.New("timestamp: " + formatTimestamp(ts) + ": nanos not in range [0, 1e9)")
+	}
+	return nil
+}
+
+// formatTimestamp is equivalent to fmt.Sprintf("%#v", ts)
+// but avoids the escape incurred by using fmt.Sprintf, eliminating
+// unnecessary heap allocations.
+func formatTimestamp(ts *types.Timestamp) string {
+	if ts == nil {
+		return "nil"
+	}
+
+	seconds := strconv.FormatInt(ts.Seconds, 10)
+	nanos := strconv.FormatInt(int64(ts.Nanos), 10)
+	return "&types.Timestamp{Seconds: " + seconds + ",\nNanos: " + nanos + ",\n}"
+}
+
+func sizeOfStdTime(t time.Time) int {
+	ts, err := timestampProto(t)
+	if err != nil {
+		return 0
+	}
+	return ts.Size()
+}
+
+func stdTimeMarshalTo(t time.Time, data []byte) (int, error) {
+	ts, err := timestampProto(t)
+	if err != nil {
+		return 0, err
+	}
+	return ts.MarshalTo(data)
+}
+
+func stdTimeUnmarshal(t *time.Time, data []byte) error {
+	ts := &types.Timestamp{}
+	if err := ts.Unmarshal(data); err != nil {
+		return err
+	}
+	tt, err := timestampFromProto(ts)
+	if err != nil {
+		return err
+	}
+	*t = tt
+	return nil
+}
+
+func timestampFromProto(ts *types.Timestamp) (time.Time, error) {
+	// Don't return the zero value on error, because corresponds to a valid
+	// timestamp. Instead return whatever time.Unix gives us.
+	var t time.Time
+	if ts == nil {
+		t = time.Unix(0, 0).UTC() // treat nil like the empty Timestamp
+	} else {
+		t = time.Unix(ts.Seconds, int64(ts.Nanos)).UTC()
+	}
+	return t, validateTimestamp(ts)
+}
+
+func timestampProto(t time.Time) (types.Timestamp, error) {
+	ts := types.Timestamp{
+		Seconds: t.Unix(),
+		Nanos:   int32(t.Nanosecond()),
+	}
+	return ts, validateTimestamp(&ts)
+}

app/vlinsert/loki/types.go

@@ -0,0 +1,481 @@
+package loki
+
+// source: https://raw.githubusercontent.com/grafana/loki/main/pkg/push/types.go
+// Licensed under the Apache License, Version 2.0 (the "License");
+// https://github.com/grafana/loki/blob/main/pkg/push/LICENSE
+
+import (
+	"fmt"
+	"io"
+	"time"
+)
+
+// Stream contains a unique labels set as a string and a set of entries for it.
+// We are not using the proto generated version but this custom one so that we
+// can improve serialization see benchmark.
+type Stream struct {
+	Labels  string  `protobuf:"bytes,1,opt,name=labels,proto3" json:"labels"`
+	Entries []Entry `protobuf:"bytes,2,rep,name=entries,proto3,customtype=EntryAdapter" json:"entries"`
+	Hash    uint64  `protobuf:"varint,3,opt,name=hash,proto3" json:"-"`
+}
+
+// Entry is a log entry with a timestamp.
+type Entry struct {
+	Timestamp time.Time `protobuf:"bytes,1,opt,name=timestamp,proto3,stdtime" json:"ts"`
+	Line      string    `protobuf:"bytes,2,opt,name=line,proto3" json:"line"`
+}
+
+// Marshal implements the proto.Marshaler interface.
+func (m *Stream) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalToSizedBuffer(dAtA[:size])
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+// MarshalTo marshals m to dst.
+func (m *Stream) MarshalTo(dAtA []byte) (int, error) {
+	size := m.Size()
+	return m.MarshalToSizedBuffer(dAtA[:size])
+}
+
+// MarshalToSizedBuffer marshals m to the sized buffer.
+func (m *Stream) MarshalToSizedBuffer(dAtA []byte) (int, error) {
+	i := len(dAtA)
+	_ = i
+	var l int
+	_ = l
+	if m.Hash != 0 {
+		i = encodeVarintPush(dAtA, i, m.Hash)
+		i--
+		dAtA[i] = 0x18
+	}
+	if len(m.Entries) > 0 {
+		for iNdEx := len(m.Entries) - 1; iNdEx >= 0; iNdEx-- {
+			{
+				size, err := m.Entries[iNdEx].MarshalToSizedBuffer(dAtA[:i])
+				if err != nil {
+					return 0, err
+				}
+				i -= size
+				i = encodeVarintPush(dAtA, i, uint64(size))
+			}
+			i--
+			dAtA[i] = 0x12
+		}
+	}
+	if len(m.Labels) > 0 {
+		i -= len(m.Labels)
+		copy(dAtA[i:], m.Labels)
+		i = encodeVarintPush(dAtA, i, uint64(len(m.Labels)))
+		i--
+		dAtA[i] = 0xa
+	}
+	return len(dAtA) - i, nil
+}
+
+// Marshal implements the proto.Marshaler interface.
+func (m *Entry) Marshal() (dAtA []byte, err error) {
+	size := m.Size()
+	dAtA = make([]byte, size)
+	n, err := m.MarshalToSizedBuffer(dAtA[:size])
+	if err != nil {
+		return nil, err
+	}
+	return dAtA[:n], nil
+}
+
+// MarshalTo marshals m to dst.
+func (m *Entry) MarshalTo(dAtA []byte) (int, error) {
+	size := m.Size()
+	return m.MarshalToSizedBuffer(dAtA[:size])
+}
+
+// MarshalToSizedBuffer marshals m to the sized buffer.
+func (m *Entry) MarshalToSizedBuffer(dAtA []byte) (int, error) {
+	i := len(dAtA)
+	_ = i
+	var l int
+	_ = l
+	if len(m.Line) > 0 {
+		i -= len(m.Line)
+		copy(dAtA[i:], m.Line)
+		i = encodeVarintPush(dAtA, i, uint64(len(m.Line)))
+		i--
+		dAtA[i] = 0x12
+	}
+	n7, err7 := stdTimeMarshalTo(m.Timestamp, dAtA[i-sizeOfStdTime(m.Timestamp):])
+	if err7 != nil {
+		return 0, err7
+	}
+	i -= n7
+	i = encodeVarintPush(dAtA, i, uint64(n7))
+	i--
+	dAtA[i] = 0xa
+	return len(dAtA) - i, nil
+}
+
+// Unmarshal unmarshals the given data into m.
+func (m *Stream) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowPush
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= uint64(b&0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: StreamAdapter: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: StreamAdapter: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Labels", wireType)
+			}
+			var stringLen uint64
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowPush
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				stringLen |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			intStringLen := int(stringLen)
+			if intStringLen < 0 {
+				return ErrInvalidLengthPush
+			}
+			postIndex := iNdEx + intStringLen
+			if postIndex < 0 {
+				return ErrInvalidLengthPush
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.Labels = string(dAtA[iNdEx:postIndex])
+			iNdEx = postIndex
+		case 2:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Entries", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowPush
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				msglen |= int(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthPush
+			}
+			postIndex := iNdEx + msglen
+			if postIndex < 0 {
+				return ErrInvalidLengthPush
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.Entries = append(m.Entries, Entry{})
+			if err := m.Entries[len(m.Entries)-1].Unmarshal(dAtA[iNdEx:postIndex]); err != nil {
+				return err
+			}
+			iNdEx = postIndex
+		case 3:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Hash", wireType)
+			}
+			m.Hash = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowPush
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.Hash |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		default:
+			iNdEx = preIndex
+			skippy, err := skipPush(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthPush
+			}
+			if (iNdEx + skippy) < 0 {
+				return ErrInvalidLengthPush
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
+
+// Unmarshal unmarshals the given data into m.
+func (m *Entry) Unmarshal(dAtA []byte) error {
+	l := len(dAtA)
+	iNdEx := 0
+	for iNdEx < l {
+		preIndex := iNdEx
+		var wire uint64
+		for shift := uint(0); ; shift += 7 {
+			if shift >= 64 {
+				return ErrIntOverflowPush
+			}
+			if iNdEx >= l {
+				return io.ErrUnexpectedEOF
+			}
+			b := dAtA[iNdEx]
+			iNdEx++
+			wire |= uint64(b&0x7F) << shift
+			if b < 0x80 {
+				break
+			}
+		}
+		fieldNum := int32(wire >> 3)
+		wireType := int(wire & 0x7)
+		if wireType == 4 {
+			return fmt.Errorf("proto: EntryAdapter: wiretype end group for non-group")
+		}
+		if fieldNum <= 0 {
+			return fmt.Errorf("proto: EntryAdapter: illegal tag %d (wire type %d)", fieldNum, wire)
+		}
+		switch fieldNum {
+		case 1:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Timestamp", wireType)
+			}
+			var msglen int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowPush
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				msglen |= int(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			if msglen < 0 {
+				return ErrInvalidLengthPush
+			}
+			postIndex := iNdEx + msglen
+			if postIndex < 0 {
+				return ErrInvalidLengthPush
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			if err := stdTimeUnmarshal(&m.Timestamp, dAtA[iNdEx:postIndex]); err != nil {
+				return err
+			}
+			iNdEx = postIndex
+		case 2:
+			if wireType != 2 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Line", wireType)
+			}
+			var stringLen uint64
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowPush
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				stringLen |= uint64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			intStringLen := int(stringLen)
+			if intStringLen < 0 {
+				return ErrInvalidLengthPush
+			}
+			postIndex := iNdEx + intStringLen
+			if postIndex < 0 {
+				return ErrInvalidLengthPush
+			}
+			if postIndex > l {
+				return io.ErrUnexpectedEOF
+			}
+			m.Line = string(dAtA[iNdEx:postIndex])
+			iNdEx = postIndex
+		default:
+			iNdEx = preIndex
+			skippy, err := skipPush(dAtA[iNdEx:])
+			if err != nil {
+				return err
+			}
+			if skippy < 0 {
+				return ErrInvalidLengthPush
+			}
+			if (iNdEx + skippy) < 0 {
+				return ErrInvalidLengthPush
+			}
+			if (iNdEx + skippy) > l {
+				return io.ErrUnexpectedEOF
+			}
+			iNdEx += skippy
+		}
+	}
+
+	if iNdEx > l {
+		return io.ErrUnexpectedEOF
+	}
+	return nil
+}
+
+// Size returns the size of the serialized Stream.
+func (m *Stream) Size() (n int) {
+	if m == nil {
+		return 0
+	}
+	var l int
+	_ = l
+	l = len(m.Labels)
+	if l > 0 {
+		n += 1 + l + sovPush(uint64(l))
+	}
+	if len(m.Entries) > 0 {
+		for _, e := range m.Entries {
+			l = e.Size()
+			n += 1 + l + sovPush(uint64(l))
+		}
+	}
+	if m.Hash != 0 {
+		n += 1 + sovPush(m.Hash)
+	}
+	return n
+}
+
+// Size returns the size of the serialized Entry
+func (m *Entry) Size() (n int) {
+	if m == nil {
+		return 0
+	}
+	var l int
+	_ = l
+	l = sizeOfStdTime(m.Timestamp)
+	n += 1 + l + sovPush(uint64(l))
+	l = len(m.Line)
+	if l > 0 {
+		n += 1 + l + sovPush(uint64(l))
+	}
+	return n
+}
+
+// Equal returns true if the two Streams are equal.
+func (m *Stream) Equal(that interface{}) bool {
+	if that == nil {
+		return m == nil
+	}
+
+	that1, ok := that.(*Stream)
+	if !ok {
+		that2, ok := that.(Stream)
+		if ok {
+			that1 = &that2
+		} else {
+			return false
+		}
+	}
+	if that1 == nil {
+		return m == nil
+	} else if m == nil {
+		return false
+	}
+	if m.Labels != that1.Labels {
+		return false
+	}
+	if len(m.Entries) != len(that1.Entries) {
+		return false
+	}
+	for i := range m.Entries {
+		if !m.Entries[i].Equal(that1.Entries[i]) {
+			return false
+		}
+	}
+	return m.Hash == that1.Hash
+}
+
+// Equal returns true if the two Entries are equal.
+func (m *Entry) Equal(that interface{}) bool {
+	if that == nil {
+		return m == nil
+	}
+
+	that1, ok := that.(*Entry)
+	if !ok {
+		that2, ok := that.(Entry)
+		if ok {
+			that1 = &that2
+		} else {
+			return false
+		}
+	}
+	if that1 == nil {
+		return m == nil
+	} else if m == nil {
+		return false
+	}
+	if !m.Timestamp.Equal(that1.Timestamp) {
+		return false
+	}
+	if m.Line != that1.Line {
+		return false
+	}
+	return true
+}

app/vlinsert/main.go

@@ -0,0 +1,43 @@
+package vlinsert
+
+import (
+	"net/http"
+	"strings"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlinsert/elasticsearch"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlinsert/jsonline"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlinsert/loki"
+)
+
+// Init initializes vlinsert
+func Init() {
+}
+
+// Stop stops vlinsert
+func Stop() {
+}
+
+// RequestHandler handles insert requests for VictoriaLogs
+func RequestHandler(w http.ResponseWriter, r *http.Request) bool {
+	path := r.URL.Path
+	if !strings.HasPrefix(path, "/insert/") {
+		// Skip requests, which do not start with /insert/, since these aren't our requests.
+		return false
+	}
+	path = strings.TrimPrefix(path, "/insert")
+	path = strings.ReplaceAll(path, "//", "/")
+
+	if path == "/jsonline" {
+		return jsonline.RequestHandler(w, r)
+	}
+	switch {
+	case strings.HasPrefix(path, "/elasticsearch/"):
+		path = strings.TrimPrefix(path, "/elasticsearch")
+		return elasticsearch.RequestHandler(path, w, r)
+	case strings.HasPrefix(path, "/loki/"):
+		path = strings.TrimPrefix(path, "/loki")
+		return loki.RequestHandler(path, w, r)
+	default:
+		return false
+	}
+}

app/vlselect/logsql/logsql.go

@@ -0,0 +1,56 @@
+package logsql
+
+import (
+	"net/http"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+)
+
+var (
+	maxSortBufferSize = flagutil.NewBytes("select.maxSortBufferSize", 1024*1024, "Query results from /select/logsql/query are automatically sorted by _time "+
+		"if their summary size doesn't exceed this value; otherwise, query results are streamed in the response without sorting; "+
+		"too big value for this flag may result in high memory usage since the sorting is performed in memory")
+)
+
+// ProcessQueryRequest handles /select/logsql/query request
+func ProcessQueryRequest(w http.ResponseWriter, r *http.Request, stopCh <-chan struct{}) {
+	// Extract tenantID
+	tenantID, err := logstorage.GetTenantIDFromRequest(r)
+	if err != nil {
+		httpserver.Errorf(w, r, "%s", err)
+		return
+	}
+
+	qStr := r.FormValue("query")
+	q, err := logstorage.ParseQuery(qStr)
+	if err != nil {
+		httpserver.Errorf(w, r, "cannot parse query [%s]: %s", qStr, err)
+		return
+	}
+	w.Header().Set("Content-Type", "application/stream+json; charset=utf-8")
+
+	sw := getSortWriter()
+	sw.Init(w, maxSortBufferSize.IntN())
+	tenantIDs := []logstorage.TenantID{tenantID}
+	vlstorage.RunQuery(tenantIDs, q, stopCh, func(columns []logstorage.BlockColumn) {
+		if len(columns) == 0 {
+			return
+		}
+		rowsCount := len(columns[0].Values)
+
+		bb := blockResultPool.Get()
+		for rowIdx := 0; rowIdx < rowsCount; rowIdx++ {
+			WriteJSONRow(bb, columns, rowIdx)
+		}
+		sw.MustWrite(bb.B)
+		blockResultPool.Put(bb)
+	})
+	sw.FinalFlush()
+	putSortWriter(sw)
+}
+
+var blockResultPool bytesutil.ByteBufferPool

app/vlselect/logsql/query_response.qtpl

@@ -0,0 +1,41 @@
+{% import (
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+) %}
+
+{% stripspace %}
+
+// JSONRow creates JSON row from the given fields.
+{% func JSONRow(columns []logstorage.BlockColumn, rowIdx int) %}
+{
+	{% code c := &columns[0] %}
+	{%q= c.Name %}:{%q= c.Values[rowIdx] %}
+	{% code columns = columns[1:] %}
+	{% for colIdx := range columns %}
+		{% code c := &columns[colIdx] %}
+		,{%q= c.Name %}:{%q= c.Values[rowIdx] %}
+	{% endfor %}
+}{% newline %}
+{% endfunc %}
+
+// JSONRows prints formatted rows
+{% func JSONRows(rows [][]logstorage.Field) %}
+	{% if len(rows) == 0 %}
+		{% return %}
+	{% endif %}
+	{% for _, fields := range rows %}
+	{
+		{% if len(fields) > 0 %}
+			{% code
+				f := fields[0]
+				fields = fields[1:]
+			%}
+			{%q= f.Name %}:{%q= f.Value %}
+			{% for _, f := range fields %}
+				,{%q= f.Name %}:{%q= f.Value %}
+			{% endfor %}
+		{% endif %}
+	}{% newline %}
+	{% endfor %}
+{% endfunc %}
+
+{% endstripspace %}

app/vlselect/logsql/query_response.qtpl.go

@@ -0,0 +1,166 @@
+// Code generated by qtc from "query_response.qtpl". DO NOT EDIT.
+// See https://github.com/valyala/quicktemplate for details.
+
+//line app/vlselect/logsql/query_response.qtpl:1
+package logsql
+
+//line app/vlselect/logsql/query_response.qtpl:1
+import (
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+)
+
+// JSONRow creates JSON row from the given fields.
+
+//line app/vlselect/logsql/query_response.qtpl:8
+import (
+	qtio422016 "io"
+
+	qt422016 "github.com/valyala/quicktemplate"
+)
+
+//line app/vlselect/logsql/query_response.qtpl:8
+var (
+	_ = qtio422016.Copy
+	_ = qt422016.AcquireByteBuffer
+)
+
+//line app/vlselect/logsql/query_response.qtpl:8
+func StreamJSONRow(qw422016 *qt422016.Writer, columns []logstorage.BlockColumn, rowIdx int) {
+//line app/vlselect/logsql/query_response.qtpl:8
+	qw422016.N().S(`{`)
+//line app/vlselect/logsql/query_response.qtpl:10
+	c := &columns[0]
+
+//line app/vlselect/logsql/query_response.qtpl:11
+	qw422016.N().Q(c.Name)
+//line app/vlselect/logsql/query_response.qtpl:11
+	qw422016.N().S(`:`)
+//line app/vlselect/logsql/query_response.qtpl:11
+	qw422016.N().Q(c.Values[rowIdx])
+//line app/vlselect/logsql/query_response.qtpl:12
+	columns = columns[1:]
+
+//line app/vlselect/logsql/query_response.qtpl:13
+	for colIdx := range columns {
+//line app/vlselect/logsql/query_response.qtpl:14
+		c := &columns[colIdx]
+
+//line app/vlselect/logsql/query_response.qtpl:14
+		qw422016.N().S(`,`)
+//line app/vlselect/logsql/query_response.qtpl:15
+		qw422016.N().Q(c.Name)
+//line app/vlselect/logsql/query_response.qtpl:15
+		qw422016.N().S(`:`)
+//line app/vlselect/logsql/query_response.qtpl:15
+		qw422016.N().Q(c.Values[rowIdx])
+//line app/vlselect/logsql/query_response.qtpl:16
+	}
+//line app/vlselect/logsql/query_response.qtpl:16
+	qw422016.N().S(`}`)
+//line app/vlselect/logsql/query_response.qtpl:17
+	qw422016.N().S(`
+`)
+//line app/vlselect/logsql/query_response.qtpl:18
+}
+
+//line app/vlselect/logsql/query_response.qtpl:18
+func WriteJSONRow(qq422016 qtio422016.Writer, columns []logstorage.BlockColumn, rowIdx int) {
+//line app/vlselect/logsql/query_response.qtpl:18
+	qw422016 := qt422016.AcquireWriter(qq422016)
+//line app/vlselect/logsql/query_response.qtpl:18
+	StreamJSONRow(qw422016, columns, rowIdx)
+//line app/vlselect/logsql/query_response.qtpl:18
+	qt422016.ReleaseWriter(qw422016)
+//line app/vlselect/logsql/query_response.qtpl:18
+}
+
+//line app/vlselect/logsql/query_response.qtpl:18
+func JSONRow(columns []logstorage.BlockColumn, rowIdx int) string {
+//line app/vlselect/logsql/query_response.qtpl:18
+	qb422016 := qt422016.AcquireByteBuffer()
+//line app/vlselect/logsql/query_response.qtpl:18
+	WriteJSONRow(qb422016, columns, rowIdx)
+//line app/vlselect/logsql/query_response.qtpl:18
+	qs422016 := string(qb422016.B)
+//line app/vlselect/logsql/query_response.qtpl:18
+	qt422016.ReleaseByteBuffer(qb422016)
+//line app/vlselect/logsql/query_response.qtpl:18
+	return qs422016
+//line app/vlselect/logsql/query_response.qtpl:18
+}
+
+// JSONRows prints formatted rows
+
+//line app/vlselect/logsql/query_response.qtpl:21
+func StreamJSONRows(qw422016 *qt422016.Writer, rows [][]logstorage.Field) {
+//line app/vlselect/logsql/query_response.qtpl:22
+	if len(rows) == 0 {
+//line app/vlselect/logsql/query_response.qtpl:23
+		return
+//line app/vlselect/logsql/query_response.qtpl:24
+	}
+//line app/vlselect/logsql/query_response.qtpl:25
+	for _, fields := range rows {
+//line app/vlselect/logsql/query_response.qtpl:25
+		qw422016.N().S(`{`)
+//line app/vlselect/logsql/query_response.qtpl:27
+		if len(fields) > 0 {
+//line app/vlselect/logsql/query_response.qtpl:29
+			f := fields[0]
+			fields = fields[1:]
+
+//line app/vlselect/logsql/query_response.qtpl:32
+			qw422016.N().Q(f.Name)
+//line app/vlselect/logsql/query_response.qtpl:32
+			qw422016.N().S(`:`)
+//line app/vlselect/logsql/query_response.qtpl:32
+			qw422016.N().Q(f.Value)
+//line app/vlselect/logsql/query_response.qtpl:33
+			for _, f := range fields {
+//line app/vlselect/logsql/query_response.qtpl:33
+				qw422016.N().S(`,`)
+//line app/vlselect/logsql/query_response.qtpl:34
+				qw422016.N().Q(f.Name)
+//line app/vlselect/logsql/query_response.qtpl:34
+				qw422016.N().S(`:`)
+//line app/vlselect/logsql/query_response.qtpl:34
+				qw422016.N().Q(f.Value)
+//line app/vlselect/logsql/query_response.qtpl:35
+			}
+//line app/vlselect/logsql/query_response.qtpl:36
+		}
+//line app/vlselect/logsql/query_response.qtpl:36
+		qw422016.N().S(`}`)
+//line app/vlselect/logsql/query_response.qtpl:37
+		qw422016.N().S(`
+`)
+//line app/vlselect/logsql/query_response.qtpl:38
+	}
+//line app/vlselect/logsql/query_response.qtpl:39
+}
+
+//line app/vlselect/logsql/query_response.qtpl:39
+func WriteJSONRows(qq422016 qtio422016.Writer, rows [][]logstorage.Field) {
+//line app/vlselect/logsql/query_response.qtpl:39
+	qw422016 := qt422016.AcquireWriter(qq422016)
+//line app/vlselect/logsql/query_response.qtpl:39
+	StreamJSONRows(qw422016, rows)
+//line app/vlselect/logsql/query_response.qtpl:39
+	qt422016.ReleaseWriter(qw422016)
+//line app/vlselect/logsql/query_response.qtpl:39
+}
+
+//line app/vlselect/logsql/query_response.qtpl:39
+func JSONRows(rows [][]logstorage.Field) string {
+//line app/vlselect/logsql/query_response.qtpl:39
+	qb422016 := qt422016.AcquireByteBuffer()
+//line app/vlselect/logsql/query_response.qtpl:39
+	WriteJSONRows(qb422016, rows)
+//line app/vlselect/logsql/query_response.qtpl:39
+	qs422016 := string(qb422016.B)
+//line app/vlselect/logsql/query_response.qtpl:39
+	qt422016.ReleaseByteBuffer(qb422016)
+//line app/vlselect/logsql/query_response.qtpl:39
+	return qs422016
+//line app/vlselect/logsql/query_response.qtpl:39
+}

app/vlselect/logsql/sort_writer.go

@@ -0,0 +1,225 @@
+package logsql
+
+import (
+	"bytes"
+	"io"
+	"sort"
+	"sync"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logjson"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+)
+
+func getSortWriter() *sortWriter {
+	v := sortWriterPool.Get()
+	if v == nil {
+		return &sortWriter{}
+	}
+	return v.(*sortWriter)
+}
+
+func putSortWriter(sw *sortWriter) {
+	sw.reset()
+	sortWriterPool.Put(sw)
+}
+
+var sortWriterPool sync.Pool
+
+// sortWriter expects JSON line stream to be written to it.
+//
+// It buffers the incoming data until its size reaches maxBufLen.
+// Then it streams the buffered data and all the incoming data to w.
+//
+// The FinalFlush() must be called when all the data is written.
+// If the buf isn't empty at FinalFlush() call, then the buffered data
+// is sorted by _time field.
+type sortWriter struct {
+	mu         sync.Mutex
+	w          io.Writer
+	maxBufLen  int
+	buf        []byte
+	bufFlushed bool
+
+	hasErr bool
+}
+
+func (sw *sortWriter) reset() {
+	sw.w = nil
+	sw.maxBufLen = 0
+	sw.buf = sw.buf[:0]
+	sw.bufFlushed = false
+	sw.hasErr = false
+}
+
+func (sw *sortWriter) Init(w io.Writer, maxBufLen int) {
+	sw.reset()
+
+	sw.w = w
+	sw.maxBufLen = maxBufLen
+}
+
+func (sw *sortWriter) MustWrite(p []byte) {
+	sw.mu.Lock()
+	defer sw.mu.Unlock()
+
+	if sw.hasErr {
+		return
+	}
+
+	if sw.bufFlushed {
+		if _, err := sw.w.Write(p); err != nil {
+			sw.hasErr = true
+		}
+		return
+	}
+	if len(sw.buf)+len(p) < sw.maxBufLen {
+		sw.buf = append(sw.buf, p...)
+		return
+	}
+	sw.bufFlushed = true
+	if len(sw.buf) > 0 {
+		if _, err := sw.w.Write(sw.buf); err != nil {
+			sw.hasErr = true
+			return
+		}
+		sw.buf = sw.buf[:0]
+	}
+	if _, err := sw.w.Write(p); err != nil {
+		sw.hasErr = true
+	}
+}
+
+func (sw *sortWriter) FinalFlush() {
+	if sw.hasErr || sw.bufFlushed {
+		return
+	}
+	rs := getRowsSorter()
+	rs.parseRows(sw.buf)
+	rs.sort()
+	WriteJSONRows(sw.w, rs.rows)
+	putRowsSorter(rs)
+}
+
+func getRowsSorter() *rowsSorter {
+	v := rowsSorterPool.Get()
+	if v == nil {
+		return &rowsSorter{}
+	}
+	return v.(*rowsSorter)
+}
+
+func putRowsSorter(rs *rowsSorter) {
+	rs.reset()
+	rowsSorterPool.Put(rs)
+}
+
+var rowsSorterPool sync.Pool
+
+type rowsSorter struct {
+	buf       []byte
+	fieldsBuf []logstorage.Field
+	rows      [][]logstorage.Field
+	times     []string
+}
+
+func (rs *rowsSorter) reset() {
+	rs.buf = rs.buf[:0]
+
+	fieldsBuf := rs.fieldsBuf
+	for i := range fieldsBuf {
+		fieldsBuf[i].Reset()
+	}
+	rs.fieldsBuf = fieldsBuf[:0]
+
+	rows := rs.rows
+	for i := range rows {
+		rows[i] = nil
+	}
+	rs.rows = rows[:0]
+
+	times := rs.times
+	for i := range times {
+		times[i] = ""
+	}
+	rs.times = times[:0]
+}
+
+func (rs *rowsSorter) parseRows(src []byte) {
+	rs.reset()
+
+	buf := rs.buf
+	fieldsBuf := rs.fieldsBuf
+	rows := rs.rows
+	times := rs.times
+
+	p := logjson.GetParser()
+	for len(src) > 0 {
+		var line []byte
+		n := bytes.IndexByte(src, '\n')
+		if n < 0 {
+			line = src
+			src = nil
+		} else {
+			line = src[:n]
+			src = src[n+1:]
+		}
+		if len(line) == 0 {
+			continue
+		}
+
+		if err := p.ParseLogMessage(line); err != nil {
+			logger.Panicf("BUG: unexpected invalid JSON line: %s", err)
+		}
+
+		timeValue := ""
+		fieldsBufLen := len(fieldsBuf)
+		for _, f := range p.Fields {
+			bufLen := len(buf)
+			buf = append(buf, f.Name...)
+			name := bytesutil.ToUnsafeString(buf[bufLen:])
+
+			bufLen = len(buf)
+			buf = append(buf, f.Value...)
+			value := bytesutil.ToUnsafeString(buf[bufLen:])
+
+			fieldsBuf = append(fieldsBuf, logstorage.Field{
+				Name:  name,
+				Value: value,
+			})
+
+			if name == "_time" {
+				timeValue = value
+			}
+		}
+		rows = append(rows, fieldsBuf[fieldsBufLen:])
+		times = append(times, timeValue)
+	}
+	logjson.PutParser(p)
+
+	rs.buf = buf
+	rs.fieldsBuf = fieldsBuf
+	rs.rows = rows
+	rs.times = times
+}
+
+func (rs *rowsSorter) Len() int {
+	return len(rs.rows)
+}
+
+func (rs *rowsSorter) Less(i, j int) bool {
+	times := rs.times
+	return times[i] < times[j]
+}
+
+func (rs *rowsSorter) Swap(i, j int) {
+	times := rs.times
+	rows := rs.rows
+	times[i], times[j] = times[j], times[i]
+	rows[i], rows[j] = rows[j], rows[i]
+}
+
+func (rs *rowsSorter) sort() {
+	sort.Sort(rs)
+}

app/vlselect/logsql/sort_writer_test.go

@@ -0,0 +1,39 @@
+package logsql
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+)
+
+func TestSortWriter(t *testing.T) {
+	f := func(maxBufLen int, data string, expectedResult string) {
+		t.Helper()
+
+		var bb bytes.Buffer
+		sw := getSortWriter()
+		sw.Init(&bb, maxBufLen)
+
+		for _, s := range strings.Split(data, "\n") {
+			sw.MustWrite([]byte(s + "\n"))
+		}
+		sw.FinalFlush()
+		putSortWriter(sw)
+
+		result := bb.String()
+		if result != expectedResult {
+			t.Fatalf("unexpected result;\ngot\n%s\nwant\n%s", result, expectedResult)
+		}
+	}
+
+	f(100, "", "")
+	f(100, "{}", "{}\n")
+
+	data := `{"_time":"def","_msg":"xxx"}
+{"_time":"abc","_msg":"foo"}`
+	resultExpected := `{"_time":"abc","_msg":"foo"}
+{"_time":"def","_msg":"xxx"}
+`
+	f(100, data, resultExpected)
+	f(10, data, data+"\n")
+}

app/vlselect/main.go

@@ -0,0 +1,162 @@
+package vlselect
+
+import (
+	"embed"
+	"flag"
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vlselect/logsql"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/httputils"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/timerpool"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+var (
+	maxConcurrentRequests = flag.Int("search.maxConcurrentRequests", getDefaultMaxConcurrentRequests(), "The maximum number of concurrent search requests. "+
+		"It shouldn't be high, since a single request can saturate all the CPU cores, while many concurrently executed requests may require high amounts of memory. "+
+		"See also -search.maxQueueDuration")
+	maxQueueDuration = flag.Duration("search.maxQueueDuration", 10*time.Second, "The maximum time the search request waits for execution when -search.maxConcurrentRequests "+
+		"limit is reached; see also -search.maxQueryDuration")
+	maxQueryDuration = flag.Duration("search.maxQueryDuration", time.Second*30, "The maximum duration for query execution")
+)
+
+func getDefaultMaxConcurrentRequests() int {
+	n := cgroup.AvailableCPUs()
+	if n <= 4 {
+		n *= 2
+	}
+	if n > 16 {
+		// A single request can saturate all the CPU cores, so there is no sense
+		// in allowing higher number of concurrent requests - they will just contend
+		// for unavailable CPU time.
+		n = 16
+	}
+	return n
+}
+
+// Init initializes vlselect
+func Init() {
+	concurrencyLimitCh = make(chan struct{}, *maxConcurrentRequests)
+}
+
+// Stop stops vlselect
+func Stop() {
+}
+
+var concurrencyLimitCh chan struct{}
+
+var (
+	concurrencyLimitReached = metrics.NewCounter(`vl_concurrent_select_limit_reached_total`)
+	concurrencyLimitTimeout = metrics.NewCounter(`vl_concurrent_select_limit_timeout_total`)
+
+	_ = metrics.NewGauge(`vl_concurrent_select_capacity`, func() float64 {
+		return float64(cap(concurrencyLimitCh))
+	})
+	_ = metrics.NewGauge(`vl_concurrent_select_current`, func() float64 {
+		return float64(len(concurrencyLimitCh))
+	})
+)
+
+//go:embed vmui
+var vmuiFiles embed.FS
+
+var vmuiFileServer = http.FileServer(http.FS(vmuiFiles))
+
+// RequestHandler handles select requests for VictoriaLogs
+func RequestHandler(w http.ResponseWriter, r *http.Request) bool {
+	path := r.URL.Path
+	if !strings.HasPrefix(path, "/select/") {
+		// Skip requests, which do not start with /select/, since these aren't our requests.
+		return false
+	}
+	path = strings.TrimPrefix(path, "/select")
+	path = strings.ReplaceAll(path, "//", "/")
+
+	if path == "/vmui" {
+		// VMUI access via incomplete url without `/` in the end. Redirect to complete url.
+		// Use relative redirect, since the hostname and path prefix may be incorrect if VictoriaMetrics
+		// is hidden behind vmauth or similar proxy.
+		_ = r.ParseForm()
+		newURL := "vmui/?" + r.Form.Encode()
+		httpserver.Redirect(w, newURL)
+		return true
+	}
+	if strings.HasPrefix(path, "/vmui/") {
+		r.URL.Path = path
+		vmuiFileServer.ServeHTTP(w, r)
+		return true
+	}
+
+	// Limit the number of concurrent queries, which can consume big amounts of CPU.
+	startTime := time.Now()
+	stopCh := r.Context().Done()
+	select {
+	case concurrencyLimitCh <- struct{}{}:
+		defer func() { <-concurrencyLimitCh }()
+	default:
+		// Sleep for a while until giving up. This should resolve short bursts in requests.
+		concurrencyLimitReached.Inc()
+		d := getMaxQueryDuration(r)
+		if d > *maxQueueDuration {
+			d = *maxQueueDuration
+		}
+		t := timerpool.Get(d)
+		select {
+		case concurrencyLimitCh <- struct{}{}:
+			timerpool.Put(t)
+			defer func() { <-concurrencyLimitCh }()
+		case <-stopCh:
+			timerpool.Put(t)
+			remoteAddr := httpserver.GetQuotedRemoteAddr(r)
+			requestURI := httpserver.GetRequestURI(r)
+			logger.Infof("client has cancelled the request after %.3f seconds: remoteAddr=%s, requestURI: %q",
+				time.Since(startTime).Seconds(), remoteAddr, requestURI)
+			return true
+		case <-t.C:
+			timerpool.Put(t)
+			concurrencyLimitTimeout.Inc()
+			err := &httpserver.ErrorWithStatusCode{
+				Err: fmt.Errorf("couldn't start executing the request in %.3f seconds, since -search.maxConcurrentRequests=%d concurrent requests "+
+					"are executed. Possible solutions: to reduce query load; to add more compute resources to the server; "+
+					"to increase -search.maxQueueDuration=%s; to increase -search.maxQueryDuration; to increase -search.maxConcurrentRequests",
+					d.Seconds(), *maxConcurrentRequests, maxQueueDuration),
+				StatusCode: http.StatusServiceUnavailable,
+			}
+			httpserver.Errorf(w, r, "%s", err)
+			return true
+		}
+	}
+
+	switch {
+	case path == "/logsql/query":
+		logsqlQueryRequests.Inc()
+		httpserver.EnableCORS(w, r)
+		logsql.ProcessQueryRequest(w, r, stopCh)
+		return true
+	default:
+		return false
+	}
+}
+
+// getMaxQueryDuration returns the maximum duration for query from r.
+func getMaxQueryDuration(r *http.Request) time.Duration {
+	dms, err := httputils.GetDuration(r, "timeout", 0)
+	if err != nil {
+		dms = 0
+	}
+	d := time.Duration(dms) * time.Millisecond
+	if d <= 0 || d > *maxQueryDuration {
+		d = *maxQueryDuration
+	}
+	return d
+}
+
+var (
+	logsqlQueryRequests = metrics.NewCounter(`vl_http_requests_total{path="/select/logsql/query"}`)
+)

app/vlselect/vmui/asset-manifest.json

@@ -0,0 +1,14 @@
+{
+  "files": {
+    "main.css": "./static/css/main.5f461a27.css",
+    "main.js": "./static/js/main.7566144a.js",
+    "static/js/522.b5ae4365.chunk.js": "./static/js/522.b5ae4365.chunk.js",
+    "static/media/Lato-Regular.ttf": "./static/media/Lato-Regular.d714fec1633b69a9c2e9.ttf",
+    "static/media/Lato-Bold.ttf": "./static/media/Lato-Bold.32360ba4b57802daa4d6.ttf",
+    "index.html": "./index.html"
+  },
+  "entrypoints": [
+    "static/css/main.5f461a27.css",
+    "static/js/main.7566144a.js"
+  ]
+}

app/vlselect/vmui/index.html

@@ -0,0 +1 @@
+<!doctype html><html lang="en"><head><meta charset="utf-8"/><link rel="icon" href="./favicon.ico"/><meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=1,user-scalable=no"/><meta name="theme-color" content="#000000"/><meta name="description" content="UI for VictoriaMetrics"/><link rel="apple-touch-icon" href="./apple-touch-icon.png"/><link rel="icon" type="image/png" sizes="32x32" href="./favicon-32x32.png"><link rel="manifest" href="./manifest.json"/><title>VM UI</title><script src="./dashboards/index.js" type="module"></script><meta name="twitter:card" content="summary_large_image"><meta name="twitter:image" content="./preview.jpg"><meta name="twitter:title" content="UI for VictoriaMetrics"><meta name="twitter:description" content="Explore and troubleshoot your VictoriaMetrics data"><meta name="twitter:site" content="@VictoriaMetrics"><meta property="og:title" content="Metric explorer for VictoriaMetrics"><meta property="og:description" content="Explore and troubleshoot your VictoriaMetrics data"><meta property="og:image" content="./preview.jpg"><meta property="og:type" content="website"><script defer="defer" src="./static/js/main.7566144a.js"></script><link href="./static/css/main.5f461a27.css" rel="stylesheet"></head><body><noscript>You need to enable JavaScript to run this app.</noscript><div id="root"></div></body></html>

app/vlselect/vmui/manifest.json

@@ -0,0 +1,20 @@
+{
+  "short_name": "Victoria Metrics UI",
+  "name": "Victoria Metrics UI is a metric explorer for Victoria Metrics",
+  "icons": [
+    {
+      "src": "favicon-32x32.png",
+      "sizes": "32x32",
+      "type": "image/png"
+    },
+    {
+      "src": "apple-touch-icon.png",
+      "type": "image/png",
+      "sizes": "192x192"
+    }
+  ],
+  "start_url": ".",
+  "display": "standalone",
+  "theme_color": "#000000",
+  "background_color": "#ffffff"
+}

app/vlselect/vmui/robots.txt

@@ -0,0 +1,3 @@
+# https://www.robotstxt.org/robotstxt.html
+User-agent: *
+Disallow:

app/vlselect/vmui/static/js/main.7566144a.js.LICENSE.txt

@@ -7,7 +7,7 @@
 /*! regenerator-runtime -- Copyright (c) 2014-present, Facebook, Inc. -- license (MIT): https://github.com/facebook/regenerator/blob/main/LICENSE */
 
 /**
- * @remix-run/router v1.3.0
+ * @remix-run/router v1.7.2
  *
  * Copyright (c) Remix Software Inc.
  *
@@ -18,7 +18,7 @@
  */
 
 /**
- * React Router DOM v6.7.0
+ * React Router DOM v6.14.2
  *
  * Copyright (c) Remix Software Inc.
  *
@@ -29,7 +29,7 @@
  */
 
 /**
- * React Router v6.7.0
+ * React Router v6.14.2
  *
  * Copyright (c) Remix Software Inc.
  *

app/vlstorage/main.go

@@ -0,0 +1,170 @@
+package vlstorage
+
+import (
+	"flag"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/fs"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logstorage"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+var (
+	retentionPeriod = flagutil.NewDuration("retentionPeriod", "7d", "Log entries with timestamps older than now-retentionPeriod are automatically deleted; "+
+		"log entries with timestamps outside the retention are also rejected during data ingestion; the minimum supported retention is 1d (one day); "+
+		"see https://docs.victoriametrics.com/VictoriaLogs/#retention")
+	futureRetention = flagutil.NewDuration("futureRetention", "2d", "Log entries with timestamps bigger than now+futureRetention are rejected during data ingestion; "+
+		"see https://docs.victoriametrics.com/VictoriaLogs/#retention")
+	storageDataPath = flag.String("storageDataPath", "victoria-logs-data", "Path to directory with the VictoriaLogs data; "+
+		"see https://docs.victoriametrics.com/VictoriaLogs/#storage")
+	inmemoryDataFlushInterval = flag.Duration("inmemoryDataFlushInterval", 5*time.Second, "The interval for guaranteed saving of in-memory data to disk. "+
+		"The saved data survives unclean shutdowns such as OOM crash, hardware reset, SIGKILL, etc. "+
+		"Bigger intervals may help increase the lifetime of flash storage with limited write cycles (e.g. Raspberry PI). "+
+		"Smaller intervals increase disk IO load. Minimum supported value is 1s")
+	logNewStreams = flag.Bool("logNewStreams", false, "Whether to log creation of new streams; this can be useful for debugging of high cardinality issues with log streams; "+
+		"see https://docs.victoriametrics.com/VictoriaLogs/keyConcepts.html#stream-fields ; see also -logIngestedRows")
+	logIngestedRows = flag.Bool("logIngestedRows", false, "Whether to log all the ingested log entries; this can be useful for debugging of data ingestion; "+
+		"see https://docs.victoriametrics.com/VictoriaLogs/data-ingestion/ ; see also -logNewStreams")
+)
+
+// Init initializes vlstorage.
+//
+// Stop must be called when vlstorage is no longer needed
+func Init() {
+	if strg != nil {
+		logger.Panicf("BUG: Init() has been already called")
+	}
+
+	if retentionPeriod.Msecs < 24*3600*1000 {
+		logger.Fatalf("-retentionPeriod cannot be smaller than a day; got %s", retentionPeriod)
+	}
+	cfg := &logstorage.StorageConfig{
+		Retention:       time.Millisecond * time.Duration(retentionPeriod.Msecs),
+		FlushInterval:   *inmemoryDataFlushInterval,
+		FutureRetention: time.Millisecond * time.Duration(futureRetention.Msecs),
+		LogNewStreams:   *logNewStreams,
+		LogIngestedRows: *logIngestedRows,
+	}
+	logger.Infof("opening storage at -storageDataPath=%s", *storageDataPath)
+	startTime := time.Now()
+	strg = logstorage.MustOpenStorage(*storageDataPath, cfg)
+
+	var ss logstorage.StorageStats
+	strg.UpdateStats(&ss)
+	logger.Infof("successfully opened storage in %.3f seconds; partsCount: %d; blocksCount: %d; rowsCount: %d; sizeBytes: %d",
+		time.Since(startTime).Seconds(), ss.FileParts, ss.FileBlocks, ss.FileRowsCount, ss.CompressedFileSize)
+	storageMetrics = initStorageMetrics(strg)
+
+	metrics.RegisterSet(storageMetrics)
+}
+
+// Stop stops vlstorage.
+func Stop() {
+	metrics.UnregisterSet(storageMetrics)
+	storageMetrics = nil
+
+	strg.MustClose()
+	strg = nil
+}
+
+var strg *logstorage.Storage
+var storageMetrics *metrics.Set
+
+// MustAddRows adds lr to vlstorage
+func MustAddRows(lr *logstorage.LogRows) {
+	strg.MustAddRows(lr)
+}
+
+// RunQuery runs the given q and calls processBlock for the returned data blocks
+func RunQuery(tenantIDs []logstorage.TenantID, q *logstorage.Query, stopCh <-chan struct{}, processBlock func(columns []logstorage.BlockColumn)) {
+	strg.RunQuery(tenantIDs, q, stopCh, processBlock)
+}
+
+func initStorageMetrics(strg *logstorage.Storage) *metrics.Set {
+	ssCache := &logstorage.StorageStats{}
+	var ssCacheLock sync.Mutex
+	var lastUpdateTime time.Time
+
+	m := func() *logstorage.StorageStats {
+		ssCacheLock.Lock()
+		defer ssCacheLock.Unlock()
+		if time.Since(lastUpdateTime) < time.Second {
+			return ssCache
+		}
+		var ss logstorage.StorageStats
+		strg.UpdateStats(&ss)
+		ssCache = &ss
+		lastUpdateTime = time.Now()
+		return ssCache
+	}
+
+	ms := metrics.NewSet()
+
+	ms.NewGauge(fmt.Sprintf(`vl_free_disk_space_bytes{path=%q}`, *storageDataPath), func() float64 {
+		return float64(fs.MustGetFreeSpace(*storageDataPath))
+	})
+
+	ms.NewGauge(`vl_active_merges{type="inmemory"}`, func() float64 {
+		return float64(m().InmemoryActiveMerges)
+	})
+	ms.NewGauge(`vl_merges_total{type="inmemory"}`, func() float64 {
+		return float64(m().InmemoryMergesTotal)
+	})
+	ms.NewGauge(`vl_active_merges{type="file"}`, func() float64 {
+		return float64(m().FileActiveMerges)
+	})
+	ms.NewGauge(`vl_merges_total{type="file"}`, func() float64 {
+		return float64(m().FileMergesTotal)
+	})
+
+	ms.NewGauge(`vl_rows{type="inmemory"}`, func() float64 {
+		return float64(m().InmemoryRowsCount)
+	})
+	ms.NewGauge(`vl_rows{type="file"}`, func() float64 {
+		return float64(m().FileRowsCount)
+	})
+	ms.NewGauge(`vl_parts{type="inmemory"}`, func() float64 {
+		return float64(m().InmemoryParts)
+	})
+	ms.NewGauge(`vl_parts{type="file"}`, func() float64 {
+		return float64(m().FileParts)
+	})
+	ms.NewGauge(`vl_blocks{type="inmemory"}`, func() float64 {
+		return float64(m().InmemoryBlocks)
+	})
+	ms.NewGauge(`vl_blocks{type="file"}`, func() float64 {
+		return float64(m().FileBlocks)
+	})
+	ms.NewGauge(`vl_partitions`, func() float64 {
+		return float64(m().PartitionsCount)
+	})
+	ms.NewGauge(`vl_streams_created_total`, func() float64 {
+		return float64(m().StreamsCreatedTotal)
+	})
+
+	ms.NewGauge(`vl_compressed_data_size_bytes{type="inmemory"}`, func() float64 {
+		return float64(m().CompressedInmemorySize)
+	})
+	ms.NewGauge(`vl_compressed_data_size_bytes{type="file"}`, func() float64 {
+		return float64(m().CompressedFileSize)
+	})
+	ms.NewGauge(`vl_uncompressed_data_size_bytes{type="inmemory"}`, func() float64 {
+		return float64(m().UncompressedInmemorySize)
+	})
+	ms.NewGauge(`vl_uncompressed_data_size_bytes{type="file"}`, func() float64 {
+		return float64(m().UncompressedFileSize)
+	})
+
+	ms.NewGauge(`vl_rows_dropped_total{reason="too_big_timestamp"}`, func() float64 {
+		return float64(m().RowsDroppedTooBigTimestamp)
+	})
+	ms.NewGauge(`vl_rows_dropped_total{reason="too_small_timestamp"}`, func() float64 {
+		return float64(m().RowsDroppedTooSmallTimestamp)
+	})
+
+	return ms
+}

app/vmagent/Makefile

@@ -85,6 +85,9 @@ vmagent-linux-arm64:
 vmagent-linux-ppc64le:
 	APP_NAME=vmagent CGO_ENABLED=0 GOOS=linux GOARCH=ppc64le $(MAKE) app-local-goos-goarch
 
+vmagent-linux-s390x:
+	APP_NAME=vmagent CGO_ENABLED=0 GOOS=linux GOARCH=s390x $(MAKE) app-local-goos-goarch
+
 vmagent-linux-386:
 	APP_NAME=vmagent CGO_ENABLED=0 GOOS=linux GOARCH=386 $(MAKE) app-local-goos-goarch
 

app/vmagent/README.md

@@ -13,7 +13,7 @@ See [Quick Start](#quick-start) for details.
 
 While VictoriaMetrics provides an efficient solution to store and observe metrics, our users needed something fast
 and RAM friendly to scrape metrics from Prometheus-compatible exporters into VictoriaMetrics.
-Also, we found that our user's infrastructure are like snowflakes in that no two are alike. Therefore we decided to add more flexibility
+Also, we found that our user's infrastructure are like snowflakes in that no two are alike. Therefore, we decided to add more flexibility
 to `vmagent` such as the ability to [accept metrics via popular push protocols](#how-to-push-data-to-vmagent)
 additionally to [discovering Prometheus-compatible targets and scraping metrics from them](#how-to-collect-metrics-in-prometheus-format).
 
@@ -25,7 +25,9 @@ additionally to [discovering Prometheus-compatible targets and scraping metrics
 * Can add, remove and modify labels (aka tags) via Prometheus relabeling. Can filter data before sending it to remote storage. See [these docs](#relabeling) for details.
 * Can accept data via all the ingestion protocols supported by VictoriaMetrics - see [these docs](#how-to-push-data-to-vmagent).
 * Can aggregate incoming samples by time and by labels before sending them to remote storage - see [these docs](https://docs.victoriametrics.com/stream-aggregation.html).
-* Can replicate collected metrics simultaneously to multiple remote storage systems - see [these docs](#replication-and-high-availability).
+* Can replicate collected metrics simultaneously to multiple Prometheus-compatible remote storage systems - see [these docs](#replication-and-high-availability).
+* Can save egress network bandwidth usage costs when [VictoriaMetrics remote write protocol](#victoriametrics-remote-write-protocol)
+  is used for sending the data to VictoriaMetrics.
 * Works smoothly in environments with unstable connections to remote storage. If the remote storage is unavailable, the collected metrics
   are buffered at `-remoteWrite.tmpDataPath`. The buffered metrics are sent to remote storage as soon as the connection
   to the remote storage is repaired. The maximum disk usage for the buffer can be limited with `-remoteWrite.maxDiskUsagePerURL`.
@@ -45,38 +47,42 @@ additionally to [discovering Prometheus-compatible targets and scraping metrics
 
 Please download `vmutils-*` archive from [releases page](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) (
 `vmagent` is also available in [docker images](https://hub.docker.com/r/victoriametrics/vmagent/tags)),
-unpack it and pass the following flags to the `vmagent` binary in order to start scraping Prometheus-compatible targets:
+unpack it and pass the following flags to the `vmagent` binary in order to start scraping Prometheus-compatible targets
+and sending the data to the Prometheus-compatible remote storage:
 
-* `-promscrape.config` with the path to Prometheus config file (usually located at `/etc/prometheus/prometheus.yml`).
+* `-promscrape.config` with the path to [Prometheus config file](https://docs.victoriametrics.com/sd_configs.html) (usually located at `/etc/prometheus/prometheus.yml`).
   The path can point either to local file or to http url. `vmagent` doesn't support some sections of Prometheus config file,
   so you may need either to delete these sections or to run `vmagent` with `-promscrape.config.strictParse=false` command-line flag.
   In this case `vmagent` ignores unsupported sections. See [the list of unsupported sections](#unsupported-prometheus-config-sections).
-* `-remoteWrite.url` with the remote storage endpoint such as VictoriaMetrics, the `-remoteWrite.url` argument can be specified
-  multiple times to replicate data concurrently to an arbitrary number of remote storage systems. See [various use cases](#use-cases).
+* `-remoteWrite.url` with Prometheus-compatible remote storage endpoint such as VictoriaMetrics, where to send the data to.
 
-Example command line:
+Example command for writing the data received via [supported push-based protocols](#how-to-push-data-to-vmagent)
+to [single-node VictoriaMetrics](https://docs.victoriametrics.com/) located at `victoria-metrics-host:8428`:
+
+```console
+/path/to/vmagent -remoteWrite.url=https://victoria-metrics-host:8428/api/v1/write
+```
+
+See [these docs](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#url-format) if you need writing
+the data to [VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html).
+
+Example command for scraping Prometheus targets and writing the data to single-node VictoriaMetrics:
 
 ```console
 /path/to/vmagent -promscrape.config=/path/to/prometheus.yml -remoteWrite.url=https://victoria-metrics-host:8428/api/v1/write
 ```
 
-Example of scrape configuration for `-promscrape.config` argument you can find [here](https://github.com/VictoriaMetrics/VictoriaMetrics/blob/master/deployment/docker/prometheus.yml)
-
 See [how to scrape Prometheus-compatible targets](#how-to-collect-metrics-in-prometheus-format) for more details.
 
 If you use single-node VictoriaMetrics, then you can discover and scrape Prometheus-compatible targets directly from VictoriaMetrics
 without the need to use `vmagent` - see [these docs](https://docs.victoriametrics.com/#how-to-scrape-prometheus-exporters-such-as-node-exporter).
 
-If you don't need to scrape Prometheus-compatible targets, then the `-promscrape.config` option isn't needed.
-For example, the following command is sufficient for accepting data via [supported push-based protocols](#how-to-push-data-to-vmagent)
-and sending it to the provided `-remoteWrite.url`:
-
-```console
-/path/to/vmagent -remoteWrite.url=https://victoria-metrics-host:8428/api/v1/write
-```
+`vmagent` can save network bandwidth usage costs under high load when [VictoriaMetrics remote write protocol is used](#victoriametrics-remote-write-protocol).
 
 See [troubleshooting docs](#troubleshooting) if you encounter common issues with `vmagent`.
 
+See [various use cases](#use-cases) for vmagent.
+
 Pass `-help` to `vmagent` in order to see [the full list of supported command-line flags with their descriptions](#advanced-usage).
 
 ## How to push data to vmagent
@@ -87,6 +93,7 @@ additionally to pull-based Prometheus-compatible targets' scraping:
 * DataDog "submit metrics" API. See [these docs](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html#how-to-send-data-from-datadog-agent).
 * InfluxDB line protocol via `http://<vmagent>:8429/write`. See [these docs](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html#how-to-send-data-from-influxdb-compatible-agents-such-as-telegraf).
 * Graphite plaintext protocol if `-graphiteListenAddr` command-line flag is set. See [these docs](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html#how-to-send-data-from-graphite-compatible-agents-such-as-statsd).
+* OpenTelemetry http API. See [these docs](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html#sending-data-via-opentelemetry).
 * OpenTSDB telnet and http protocols if `-opentsdbListenAddr` command-line flag is set. See [these docs](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html#how-to-send-data-from-opentsdb-compatible-agents).
 * Prometheus remote write protocol via `http://<vmagent>:8429/api/v1/write`.
 * JSON lines import protocol via `http://<vmagent>:8429/api/v1/import`. See [these docs](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html#how-to-import-data-in-json-line-format).
@@ -98,7 +105,7 @@ additionally to pull-based Prometheus-compatible targets' scraping:
 
 `vmagent` should be restarted in order to update config options set via command-line args.
 `vmagent` supports multiple approaches for reloading configs from updated config files such as
-`-promscrape.config`, `-remoteWrite.relabelConfig` and `-remoteWrite.urlRelabelConfig`:
+`-promscrape.config`, `-remoteWrite.relabelConfig`, `-remoteWrite.urlRelabelConfig` and `-remoteWrite.streamAggr.config`:
 
 * Sending `SIGHUP` signal to `vmagent` process:
 
@@ -120,7 +127,8 @@ data to the remote storage. It re-tries sending the data to remote storage until
 The maximum on-disk size for the buffered metrics can be limited with `-remoteWrite.maxDiskUsagePerURL`.
 
 `vmagent` works on various architectures from the IoT world - 32-bit arm, 64-bit arm, ppc64, 386, amd64.
-See [the corresponding Makefile rules](https://github.com/VictoriaMetrics/VictoriaMetrics/blob/master/app/vmagent/Makefile) for details.
+
+The `vmagent` can save network bandwidth usage costs by using [VictoriaMetrics remote write protocol](#victoriametrics-remote-write-protocol).
 
 ### Drop-in replacement for Prometheus
 
@@ -144,9 +152,28 @@ to other remote storage systems, which support Prometheus `remote_write` protoco
 
 `vmagent` replicates the collected metrics among multiple remote storage instances configured via `-remoteWrite.url` args.
 If a single remote storage instance temporarily is out of service, then the collected data remains available in another remote storage instance.
-`vmagent` buffers the collected data in files at `-remoteWrite.tmpDataPath` until the remote storage becomes available again
+`vmagent` buffers the collected data in files at `-remoteWrite.tmpDataPath` until the remote storage becomes available again,
 and then it sends the buffered data to the remote storage in order to prevent data gaps.
 
+[VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html) already supports replication,
+so there is no need in specifying multiple `-remoteWrite.url` flags when writing data to the same cluster.
+See [these docs](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#replication-and-data-safety).
+
+### Sharding among remote storages
+
+By default `vmagent` replicates data among remote storage systems enumerated via `-remoteWrite.url` command-line flag.
+If the `-remoteWrite.shardByURL` command-line flag is set, then `vmagent` spreads evenly
+the outgoing [time series](https://docs.victoriametrics.com/keyConcepts.html#time-series)
+among all the remote storage systems enumerated via `-remoteWrite.url`. Note that samples for the same
+time series are routed to the same remote storage system if `-remoteWrite.shardByURL` flag is specified.
+This allows building scalable data processing pipelines when a single remote storage cannot keep up with the data ingestion workload.
+For example, this allows building horizontally scalable [stream aggregation](https://docs.victoriametrics.com/stream-aggregation.html)
+by routing outgoing samples for the same time series of [counter](https://docs.victoriametrics.com/keyConcepts.html#counter)
+and [histogram](https://docs.victoriametrics.com/keyConcepts.html#histogram) types from top-level `vmagent` instances
+to the same second-level `vmagent` instance, so they are aggregated properly.
+
+See also [how to scrape big number of targets](#scraping-big-number-of-targets).
+
 ### Relabeling and filtering
 
 `vmagent` can add, remove or update labels on the collected data before sending it to the remote storage. Additionally,
@@ -158,7 +185,7 @@ Please see [these docs](#relabeling) for details.
 `vmagent` supports splitting the collected data between multiple destinations with the help of `-remoteWrite.urlRelabelConfig`,
 which is applied independently for each configured `-remoteWrite.url` destination. For example, it is possible to replicate or split
 data among long-term remote storage, short-term remote storage and a real-time analytical system [built on top of Kafka](https://github.com/Telefonica/prometheus-kafka-adapter).
-Note that each destination can receive it's own subset of the collected data due to per-destination relabeling via `-remoteWrite.urlRelabelConfig`.
+Note that each destination can receive its own subset of the collected data due to per-destination relabeling via `-remoteWrite.urlRelabelConfig`.
 
 ### Prometheus remote_write proxy
 
@@ -170,11 +197,37 @@ Also, Basic Auth can be enabled for the incoming `remote_write` requests with `-
 ### remote_write for clustered version
 
 While `vmagent` can accept data in several supported protocols (OpenTSDB, Influx, Prometheus, Graphite) and scrape data from various targets,
-writes are always performed in Promethes remote_write protocol. Therefore for the [clustered version](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html),
+writes are always performed in Prometheus remote_write protocol. Therefore, for the [clustered version](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html),
 the `-remoteWrite.url` command-line flag should be configured as `<schema>://<vminsert-host>:8480/insert/<accountID>/prometheus/api/v1/write`
 according to [these docs](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#url-format).
 There is also support for multitenant writes. See [these docs](#multitenancy).
 
+## VictoriaMetrics remote write protocol
+
+`vmagent` supports sending data to the configured `-remoteWrite.url` either via Prometheus remote write protocol
+or via VictoriaMetrics remote write protocol.
+
+VictoriaMetrics remote write protocol provides the following benefits comparing to Prometheus remote write protocol:
+
+- Reduced network bandwidth usage by 2x-5x. This allows saving network bandwidth usage costs when `vmagent` and
+  the configured remote storage systems are located in different datacenters, availability zones or regions.
+
+- Reduced disk read/write IO and disk space usage at `vmagent` when the remote storage is temporarily unavailable.
+  In this case `vmagent` buffers the incoming data to disk using the VictoriaMetrics remote write format.
+  This reduces disk read/write IO and disk space usage by 2x-5x comparing to Prometheus remote write format.
+
+`vmagent` automatically switches to VictoriaMetrics remote write protocol when it sends data to VictoriaMetrics components such as other `vmagent` instances,
+[single-node VictoriaMetrics](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html)
+or `vminsert` at [cluster version](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html).
+It is possible to force switch to VictoriaMetrics remote write protocol by specifying `-remoteWrite.forceVMProto`
+command-line flag for the corresponding `-remoteWrite.url`.
+It is possible to tune the compression level for VictoriaMetrics remote write protocol with `-remoteWrite.vmProtoCompressLevel` command-line flag.
+Bigger values reduce network usage at the cost of higher CPU usage. Negative values reduce CPU usage at the cost of higher network usage.
+
+`vmagent` automatically switches to Prometheus remote write protocol when it sends data to old versions of VictoriaMetrics components
+or to other Prometheus-compatible remote storage systems. It is possible to force switch to Prometheus remote write protocol
+by specifying `-remoteWrite.forcePromProto` command-line flag for the corresponding `-remoteWrite.url`.
+
 ## Multitenancy
 
 By default `vmagent` collects the data without tenant identifiers and routes it to the configured `-remoteWrite.url`.
@@ -198,7 +251,7 @@ This allows using a single `vmagent` instance in front of multiple VictoriaMetri
 If `-remoteWrite.multitenantURL` command-line flag is set and `vmagent` is configured to scrape Prometheus-compatible targets
 (e.g. if `-promscrape.config` command-line flag is set) then `vmagent` reads tenantID from `__tenant_id__` label
 for the discovered targets and routes all the metrics from this target to the given `__tenant_id__`,
-e.g. to the url `<-remoteWrite.multitnenatURL>/insert/<__tenant_id__>/prometheus/api/v1/write`.
+e.g. to the url `<-remoteWrite.multitenantURL>/insert/<__tenant_id__>/prometheus/api/v1/write`.
 
 For example, the following relabeling rule instructs sending metrics to tenantID defined in the `prometheus.io/tenant` annotation of Kubernetes pod deployment:
 
@@ -244,14 +297,14 @@ scrape_configs:
   - "My-Auth: TopSecret"
 ```
 
-* `disable_compression: true` for disabling response compression on a per-job basis. By default `vmagent` requests compressed responses
+* `disable_compression: true` for disabling response compression on a per-job basis. By default, `vmagent` requests compressed responses
   from scrape targets for saving network bandwidth.
 * `disable_keepalive: true` for disabling [HTTP keep-alive connections](https://en.wikipedia.org/wiki/HTTP_persistent_connection)
-  on a per-job basis. By default `vmagent` uses keep-alive connections to scrape targets for reducing overhead on connection re-establishing.
+  on a per-job basis. By default, `vmagent` uses keep-alive connections to scrape targets for reducing overhead on connection re-establishing.
 * `series_limit: N` for limiting the number of unique time series a single scrape target can expose. See [these docs](#cardinality-limiter).
 * `stream_parse: true` for scraping targets in a streaming manner. This may be useful when targets export big number of metrics. See [these docs](#stream-parsing-mode).
 * `scrape_align_interval: duration` for aligning scrapes to the given interval instead of using random offset
-  in the range `[0 ... scrape_interval]` for scraping each target. The random offset helps spreading scrapes evenly in time.
+  in the range `[0 ... scrape_interval]` for scraping each target. The random offset helps to spread scrapes evenly in time.
 * `scrape_offset: duration` for specifying the exact offset for scraping instead of using random offset in the range `[0 ... scrape_interval]`.
 
 See [scrape_configs docs](https://docs.victoriametrics.com/sd_configs.html#scrape_configs) for more details on all the supported options.
@@ -300,7 +353,7 @@ There is no need in specifying top-level `scrape_configs` section in these files
 
 The list of supported service discovery types is available [here](#how-to-collect-metrics-in-prometheus-format).
 
-Additionally `vmagent` doesn't support `refresh_interval` option at service discovery sections.
+Additionally, `vmagent` doesn't support `refresh_interval` option at service discovery sections.
 This option is substituted with `-promscrape.*CheckInterval` command-line options, which are specific per each service discovery type.
 See [the full list of command-line flags for vmagent](#advanced-usage).
 
@@ -422,11 +475,12 @@ VictoriaMetrics components support [Prometheus-compatible relabeling](https://pr
 with [additional enhancements](#relabeling-enhancements). The relabeling can be defined in the following places processed by `vmagent`:
 
 * At the `scrape_config -> relabel_configs` section in `-promscrape.config` file.
-  This relabeling is used for modifying labels in discovered targets and for dropping unneded targets.
+  This relabeling is used for modifying labels in discovered targets and for dropping unneeded targets.
   See [relabeling cookbook](https://docs.victoriametrics.com/relabeling.html) for details.
 
   This relabeling can be debugged by clicking the `debug` link at the corresponding target on the `http://vmagent:8429/targets` page
   or on the `http://vmagent:8429/service-discovery` page. See [these docs](#relabel-debug) for details.
+  The link is unavailable if `vmagent` runs with `-promscrape.dropOriginalLabels` command-line flag.
 
 * At the `scrape_config -> metric_relabel_configs` section in `-promscrape.config` file.
   This relabeling is used for modifying labels in scraped metrics and for dropping unneeded metrics.
@@ -474,8 +528,9 @@ The following articles contain useful information about Prometheus relabeling:
   {% endraw %}
 
 * An optional `if` filter can be used for conditional relabeling. The `if` filter may contain
-  arbitrary [time series selector](https://prometheus.io/docs/prometheus/latest/querying/basics/#time-series-selectors).
-  For example, the following relabeling rule drops metrics, which don't match `foo{bar="baz"}` series selector, while leaving the rest of metrics:
+  arbitrary [time series selector](https://docs.victoriametrics.com/keyConcepts.html#filtering).
+  The `action` is performed only for [samples](https://docs.victoriametrics.com/keyConcepts.html#raw-samples), which match the provided `if` filter.
+  For example, the following relabeling rule keeps metrics matching `foo{bar="baz"}` series selector, while dropping the rest of metrics:
 
   ```yaml
   - if: 'foo{bar="baz"}'
@@ -490,6 +545,18 @@ The following articles contain useful information about Prometheus relabeling:
     regex: 'foo;baz'
   ```
 
+  The `if` option may contain more than one filter. In this case the `action` is performed if at least a single filter
+  matches the given [sample](https://docs.victoriametrics.com/keyConcepts.html#raw-samples).
+  For example, the following relabeling rule adds `foo="bar"` label to samples with `job="foo"` or `instance="bar"` labels:
+
+  ```yaml
+  - target_label: foo
+    replacement: bar
+    if:
+    - '{job="foo"}'
+    - '{instance="bar"}'
+  ```
+
 * The `regex` value can be split into multiple lines for improved readability and maintainability.
   These lines are automatically joined with `|` char when parsed. For example, the following configs are equivalent:
 
@@ -509,7 +576,7 @@ The following articles contain useful information about Prometheus relabeling:
 * VictoriaMetrics provides the following additional relabeling actions on top of standard actions
   from the [Prometheus relabeling](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#relabel_config):
 
-  * `replace_all` replaces all of the occurrences of `regex` in the values of `source_labels` with the `replacement`
+  * `replace_all` replaces all the occurrences of `regex` in the values of `source_labels` with the `replacement`
     and stores the results in the `target_label`. For example, the following relabeling config replaces all the occurrences
     of `-` char in metric names with `_` char (e.g. `foo-bar-baz` metric name is transformed into `foo_bar_baz`):
 
@@ -521,7 +588,7 @@ The following articles contain useful information about Prometheus relabeling:
       replacement: "_"
     ```
 
-  * `labelmap_all` replaces all of the occurrences of `regex` in all the label names with the `replacement`.
+  * `labelmap_all` replaces all the occurrences of `regex` in all the label names with the `replacement`.
     For example, the following relabeling config replaces all the occurrences of `-` char in all the label names
     with `_` char (e.g. `foo-bar-baz` label name is transformed into `foo_bar_baz`):
 
@@ -607,18 +674,21 @@ provide the following tools for debugging target-level and metric-level relabeli
 - Target-level debugging (e.g. `relabel_configs` section at [scrape_configs](https://docs.victoriametrics.com/sd_configs.html#scrape_configs))
   can be performed by navigating to `http://vmagent:8429/targets` page (`http://victoriametrics:8428/targets` page for single-node VictoriaMetrics)
   and clicking the `debug target relabeling` link at the target, which must be debugged.
-  The opened page will show step-by-step results for the actual target relabeling rules applied to the discovered target labels.
+  The link is unavailable if `vmagent` runs with `-promscrape.dropOriginalLabels` command-line flag.
+  The opened page shows step-by-step results for the actual target relabeling rules applied to the discovered target labels.
+  The page shows also the target URL generated after applying all the relabeling rules.
 
   The `http://vmagent:8429/targets` page shows only active targets. If you need to understand why some target
   is dropped during the relabeling, then navigate to `http://vmagent:8428/service-discovery` page
   (`http://victoriametrics:8428/service-discovery` for single-node VictoriaMetrics), find the dropped target
-  and click the `debug` link there. The opened page will show step-by-step results for the actual relabeling rules,
-  which result to target drop.
+  and click the `debug` link there. The link is unavailable if `vmagent` runs with `-promscrape.dropOriginalLabels` command-line flag.
+  The opened page shows step-by-step results for the actual relabeling rules, which result to target drop.
 
 - Metric-level debugging (e.g. `metric_relabel_configs` section at [scrape_configs](https://docs.victoriametrics.com/sd_configs.html#scrape_configs)
   can be performed by navigating to `http://vmagent:8429/targets` page (`http://victoriametrics:8428/targets` page for single-node VictoriaMetrics)
   and clicking the `debug metrics relabeling` link at the target, which must be debugged.
-  The opened page will show step-by-step results for the actual metric relabeling rules applied to the given target labels.
+  The link is unavailable if `vmagent` runs with `-promscrape.dropOriginalLabels` command-line flag.
+  The opened page shows step-by-step results for the actual metric relabeling rules applied to the given target labels.
 
 ## Prometheus staleness markers
 
@@ -640,7 +710,7 @@ e.g. it sets `scrape_series_added` metric to zero. See [these docs](#automatical
 
 ## Stream parsing mode
 
-By default `vmagent` reads the full response body from scrape target into memory, then parses it, applies [relabeling](#relabeling)
+By default, `vmagent` reads the full response body from scrape target into memory, then parses it, applies [relabeling](#relabeling)
 and then pushes the resulting metrics to the configured `-remoteWrite.url`. This mode works good for the majority of cases
 when the scrape target exposes small number of metrics (e.g. less than 10 thousand). But this mode may take big amounts of memory
 when the scrape target exposes big number of metrics. In this case it is recommended enabling stream parsing mode.
@@ -668,8 +738,8 @@ scrape_configs:
   stream_parse: true
   static_configs:
   - targets:
-    - big-prometeus1
-    - big-prometeus2
+    - big-prometheus1
+    - big-prometheus2
   honor_labels: true
   metrics_path: /federate
   params:
@@ -677,7 +747,7 @@ scrape_configs:
 ```
 
 Note that `vmagent` in stream parsing mode stores up to `sample_limit` samples to the configured `-remoteStorage.url`
-instead of droping all the samples read from the target, because the parsed data is sent to the remote storage
+instead of dropping all the samples read from the target, because the parsed data is sent to the remote storage
 as soon as it is parsed in stream parsing mode.
 
 ## Scraping big number of targets
@@ -697,7 +767,7 @@ spread scrape targets among a cluster of two `vmagent` instances:
 The `-promscrape.cluster.memberNum` can be set to a StatefulSet pod name when `vmagent` runs in Kubernetes.
 The pod name must end with a number in the range `0 ... promscrape.cluster.memberNum-1`. For example, `-promscrape.cluster.memberNum=vmagent-0`.
 
-By default each scrape target is scraped only by a single `vmagent` instance in the cluster. If there is a need for replicating scrape targets among multiple `vmagent` instances,
+By default, each scrape target is scraped only by a single `vmagent` instance in the cluster. If there is a need for replicating scrape targets among multiple `vmagent` instances,
 then `-promscrape.cluster.replicationFactor` command-line flag must be set to the desired number of replicas. For example, the following commands
 start a cluster of three `vmagent` instances, where each target is scraped by two `vmagent` instances:
 
@@ -711,16 +781,23 @@ If each target is scraped by multiple `vmagent` instances, then data deduplicati
 The `-dedup.minScrapeInterval` must be set to the `scrape_interval` configured at `-promscrape.config`.
 See [these docs](https://docs.victoriametrics.com/#deduplication) for details.
 
+See also [how to shard data among multiple remote storage systems](#sharding-among-remote-storages).
+
+
 ## High availability
 
-It is possible to run multiple identically configured `vmagent` instances or `vmagent` [clusters](#scraping-big-number-of-targets),
-so they [scrape](#how-to-collect-metrics-in-prometheus-format) the same set of targets and push the collected data to the same set of VictoriaMetrics remote storage systems.
+It is possible to run multiple **identically configured** `vmagent` instances or `vmagent` 
+[clusters](#scraping-big-number-of-targets), so they [scrape](#how-to-collect-metrics-in-prometheus-format) 
+the same set of targets and push the collected data to the same set of VictoriaMetrics remote storage systems. 
+Two **identically configured** vmagent instances or clusters is usually called an HA pair.
 
-In this case the deduplication must be configured at VictoriaMetrics in order to de-duplicate samples received from multiple identically configured `vmagent` instances or clusters.
+When running HA pairs, [deduplication](https://docs.victoriametrics.com/#deduplication) must be configured 
+at VictoriaMetrics side in order to de-duplicate received samples.
 See [these docs](https://docs.victoriametrics.com/#deduplication) for details.
 
-It is also recommended passing different values to `-promscrape.cluster.name` command-line flag per each `vmagent` instance or per each `vmagent` cluster in HA setup.
-This is needed for proper data de-duplication. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2679) for details.
+It is also recommended passing different values to `-promscrape.cluster.name` command-line flag per each `vmagent` 
+instance or per each `vmagent` cluster in HA setup. This is needed for proper data de-duplication. 
+See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2679) for details.
 
 ## Scraping targets via a proxy
 
@@ -763,7 +840,7 @@ scrape_configs:
 
 ## Cardinality limiter
 
-By default `vmagent` doesn't limit the number of time series each scrape target can expose. 
+By default, `vmagent` doesn't limit the number of time series each scrape target can expose.
 The limit can be enforced in the following places:
 
 * Via `-promscrape.seriesLimitPerTarget` command-line option. This limit is applied individually
@@ -791,7 +868,7 @@ These metrics allow building the following alerting rules:
 
 See also `sample_limit` option at [scrape_config section](https://docs.victoriametrics.com/sd_configs.html#scrape_configs).
 
-By default `vmagent` doesn't limit the number of time series written to remote storage systems specified at `-remoteWrite.url`.
+By default, `vmagent` doesn't limit the number of time series written to remote storage systems specified at `-remoteWrite.url`.
 The limit can be enforced by setting the following command-line flags:
 
 * `-remoteWrite.maxHourlySeries` - limits the number of unique time series `vmagent` can write to remote storage systems during the last hour.
@@ -834,7 +911,7 @@ If you have suggestions for improvements or have found a bug - please open an is
 * `http://vmagent-host:8429/api/v1/targets`. This handler returns JSON response
   compatible with [the corresponding page from Prometheus API](https://prometheus.io/docs/prometheus/latest/querying/api/#targets).
 * `http://vmagent-host:8429/ready`. This handler returns http 200 status code when `vmagent` finishes
-  it's initialization for all the [service_discovery configs](https://docs.victoriametrics.com/sd_configs.html).
+  its initialization for all the [service_discovery configs](https://docs.victoriametrics.com/sd_configs.html).
   It may be useful to perform `vmagent` rolling update without any scrape loss.
 
 ## Troubleshooting
@@ -862,9 +939,9 @@ If you have suggestions for improvements or have found a bug - please open an is
 
 * The `/service-discovery` page could be useful for debugging relabeling process for scrape targets.
   This page contains original labels for targets dropped during relabeling.
-  By default the `-promscrape.maxDroppedTargets` targets are shown here. If your setup drops more targets during relabeling,
+  By default, the `-promscrape.maxDroppedTargets` targets are shown here. If your setup drops more targets during relabeling,
   then increase `-promscrape.maxDroppedTargets` command-line flag value to see all the dropped targets.
-  Note that tracking each dropped target requires up to 10Kb of RAM. Therefore big values for `-promscrape.maxDroppedTargets`
+  Note that tracking each dropped target requires up to 10Kb of RAM. Therefore, big values for `-promscrape.maxDroppedTargets`
   may result in increased memory usage if a big number of scrape targets are dropped during relabeling.
 
 * We recommend you increase `-remoteWrite.queues` if `vmagent_remotewrite_pending_data_bytes` metric exported
@@ -874,13 +951,13 @@ If you have suggestions for improvements or have found a bug - please open an is
 
 * If you see gaps in the data pushed by `vmagent` to remote storage when `-remoteWrite.maxDiskUsagePerURL` is set,
   try increasing `-remoteWrite.queues`. Such gaps may appear because `vmagent` cannot keep up with sending the collected data to remote storage.
-  Therefore it starts dropping the buffered data if the on-disk buffer size exceeds `-remoteWrite.maxDiskUsagePerURL`.
+  Therefore, it starts dropping the buffered data if the on-disk buffer size exceeds `-remoteWrite.maxDiskUsagePerURL`.
 
 * `vmagent` drops data blocks if remote storage replies with `400 Bad Request` and `409 Conflict` HTTP responses.
   The number of dropped blocks can be monitored via `vmagent_remotewrite_packets_dropped_total` metric exported at [/metrics page](#monitoring).
 
 * Use `-remoteWrite.queues=1` when `-remoteWrite.url` points to remote storage, which doesn't accept out-of-order samples (aka data backfilling).
-  Such storage systems include Prometheus, Cortex and Thanos, which typically emit `out of order sample` errors.
+  Such storage systems include Prometheus, Mimir, Cortex and Thanos, which typically emit `out of order sample` errors.
   The best solution is to use remote storage with [backfilling support](https://docs.victoriametrics.com/#backfilling) such as VictoriaMetrics.
 
 * `vmagent` buffers scraped data at the `-remoteWrite.tmpDataPath` directory until it is sent to `-remoteWrite.url`.
@@ -940,7 +1017,7 @@ See also [troubleshooting docs](https://docs.victoriametrics.com/Troubleshooting
 * [Writing metrics to Kafka](#writing-metrics-to-kafka)
 
 The enterprise version of vmagent is available for evaluation at [releases](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) page
-in `vmutils-...-enteprise.tar.gz` archives and in [docker images](https://hub.docker.com/r/victoriametrics/vmagent/tags) with tags containing `enterprise` suffix.
+in `vmutils-...-enterprise.tar.gz` archives and in [docker images](https://hub.docker.com/r/victoriametrics/vmagent/tags) with tags containing `enterprise` suffix.
 
 ### Reading metrics from Kafka
 
@@ -988,7 +1065,7 @@ data_format = "influx"
 
 These command-line flags are available only in [enterprise](https://docs.victoriametrics.com/enterprise.html) version of `vmagent`,
 which can be downloaded for evaluation from [releases](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) page
-(see `vmutils-...-enteprise.tar.gz` archives) and from [docker images](https://hub.docker.com/r/victoriametrics/vmagent/tags) with tags containing `enterprise` suffix.
+(see `vmutils-...-enterprise.tar.gz` archives) and from [docker images](https://hub.docker.com/r/victoriametrics/vmagent/tags) with tags containing `enterprise` suffix.
 
 ```
   -kafka.consumer.topic array
@@ -1054,13 +1131,13 @@ It may be needed to build `vmagent` from source code when developing or testing
 ### Development build
 
 1. [Install Go](https://golang.org/doc/install). The minimum supported version is Go 1.19.
-2. Run `make vmagent` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make vmagent` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds the `vmagent` binary and puts it into the `bin` folder.
 
 ### Production build
 
 1. [Install docker](https://docs.docker.com/install/).
-2. Run `make vmagent-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make vmagent-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `vmagent-prod` binary and puts it into the `bin` folder.
 
 ### Building docker images
@@ -1083,13 +1160,13 @@ ARM build may run on Raspberry Pi or on [energy-efficient ARM servers](https://b
 ### Development ARM build
 
 1. [Install Go](https://golang.org/doc/install). The minimum supported version is Go 1.19.
-2. Run `make vmagent-linux-arm` or `make vmagent-linux-arm64` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics)
+1. Run `make vmagent-linux-arm` or `make vmagent-linux-arm64` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics)
    It builds `vmagent-linux-arm` or `vmagent-linux-arm64` binary respectively and puts it into the `bin` folder.
 
 ### Production ARM build
 
 1. [Install docker](https://docs.docker.com/install/).
-2. Run `make vmagent-linux-arm-prod` or `make vmagent-linux-arm64-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make vmagent-linux-arm-prod` or `make vmagent-linux-arm64-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `vmagent-linux-arm-prod` or `vmagent-linux-arm64-prod` binary respectively and puts it into the `bin` folder.
 
 ## Profiling
@@ -1124,7 +1201,7 @@ It is safe sharing the collected profiles from security point of view, since the
 
 ## Advanced usage
 
-`vmagent` can be fine-tuned with various command-line flags. Run `./vmagent -help` in order to see the full list of these flags with their desciptions and default values:
+`vmagent` can be fine-tuned with various command-line flags. Run `./vmagent -help` in order to see the full list of these flags with their descriptions and default values:
 
 ```
 ./vmagent -help
@@ -1135,6 +1212,10 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
 
   -cacheExpireDuration duration
      Items are removed from in-memory caches after they aren't accessed for this duration. Lower values may reduce memory usage at the cost of higher CPU usage. See also -prevCacheRemovalPercent (default 30m0s)
+  -clients.docker
+     Decides whether a docker container be brought up automatically
+  -clients.semaphore
+     Tells if the job is running on Semaphore
   -configAuthKey string
      Authorization key for accessing /config page. It must be passed via authKey query arg
   -csvTrimTimestamp duration
@@ -1147,11 +1228,11 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -denyQueryTracing
      Whether to disable the ability to trace queries. See https://docs.victoriametrics.com/#query-tracing
   -dryRun
-     Whether to check only config files without running vmagent. The following files are checked: -promscrape.config, -remoteWrite.relabelConfig, -remoteWrite.urlRelabelConfig . Unknown config entries aren't allowed in -promscrape.config by default. This can be changed by passing -promscrape.config.strictParse=false command-line flag
+     Whether to check config files without running vmagent. The following files are checked: -promscrape.config, -remoteWrite.relabelConfig, -remoteWrite.urlRelabelConfig, -remoteWrite.streamAggr.config . Unknown config entries aren't allowed in -promscrape.config by default. This can be changed by passing -promscrape.config.strictParse=false command-line flag
   -enableTCP6
-     Whether to enable IPv6 for listening and dialing. By default only IPv4 TCP and UDP is used
+     Whether to enable IPv6 for listening and dialing. By default, only IPv4 TCP and UDP are used
   -envflag.enable
-     Whether to enable reading flags from environment variables additionally to command line. Command line flag values have priority over values from environment vars. Flags are read only from command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
+     Whether to enable reading flags from environment variables in addition to the command line. Command line flag values have priority over values from environment vars. Flags are read only from the command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
   -envflag.prefix string
      Prefix for environment variables if -envflag.enable is set
   -eula
@@ -1159,7 +1240,7 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -flagsAuthKey string
      Auth key for /flags endpoint. It must be passed via authKey query arg. It overrides httpAuth.* settings
   -fs.disableMmap
-     Whether to use pread() instead of mmap() for reading data files. By default mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
+     Whether to use pread() instead of mmap() for reading data files. By default, mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
   -graphiteListenAddr string
      TCP and UDP address to listen for Graphite plaintext data. Usually :2003 must be set. Doesn't work if empty. See also -graphiteListenAddr.useProxyProtocol
   -graphiteListenAddr.useProxyProtocol
@@ -1169,7 +1250,7 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -http.connTimeout duration
      Incoming http connections are closed after the configured timeout. This may help to spread the incoming load among a cluster of services behind a load balancer. Please note that the real timeout may be bigger by up to 10% as a protection against the thundering herd problem (default 2m0s)
   -http.disableResponseCompression
-     Disable compression of HTTP responses to save CPU resources. By default compression is enabled to save network bandwidth
+     Disable compression of HTTP responses to save CPU resources. By default, compression is enabled to save network bandwidth
   -http.idleConnTimeout duration
      Timeout for incoming idle http connections (default 1m0s)
   -http.maxGracefulShutdownDuration duration
@@ -1179,13 +1260,13 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -http.shutdownDelay duration
      Optional delay before http server shutdown. During this delay, the server returns non-OK responses from /health page, so load balancers can route new requests to other servers
   -httpAuth.password string
-     Password for HTTP Basic Auth. The authentication is disabled if -httpAuth.username is empty
+     Password for HTTP server's Basic Auth. The authentication is disabled if -httpAuth.username is empty
   -httpAuth.username string
-     Username for HTTP Basic Auth. The authentication is disabled if empty. See also -httpAuth.password
+     Username for HTTP server's Basic Auth. The authentication is disabled if empty. See also -httpAuth.password
   -httpListenAddr string
      TCP address to listen for http connections. Set this flag to empty value in order to disable listening on any port. This mode may be useful for running multiple vmagent instances on the same server. Note that /targets and /metrics pages aren't available if -httpListenAddr=''. See also -httpListenAddr.useProxyProtocol (default ":8429")
   -httpListenAddr.useProxyProtocol
-     Whether to use proxy protocol for connections accepted at -httpListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
+     Whether to use proxy protocol for connections accepted at -httpListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt . With enabled proxy protocol http server cannot serve regular /metrics endpoint. Use -pushmetrics.url for metrics pushing
   -import.maxLineLen size
      The maximum length in bytes of a single line accepted by /api/v1/import; the line length can be limited with 'max_rows_per_line' query arg passed to /api/v1/export
      Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 104857600)
@@ -1206,13 +1287,17 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -influxSkipMeasurement
      Uses '{field_name}' as a metric name while ignoring '{measurement}' and '-influxMeasurementFieldSeparator'
   -influxSkipSingleField
-     Uses '{measurement}' instead of '{measurement}{separator}{field_name}' for metic name if InfluxDB line contains only a single field
+     Uses '{measurement}' instead of '{measurement}{separator}{field_name}' for metric name if InfluxDB line contains only a single field
   -influxTrimTimestamp duration
      Trim timestamps for InfluxDB line protocol data to this duration. Minimum practical duration is 1ms. Higher duration (i.e. 1s) may be used for reducing disk space usage for timestamp data (default 1ms)
   -insert.maxQueueDuration duration
      The maximum duration to wait in the queue when -maxConcurrentInserts concurrent insert requests are executed (default 1m0s)
+  -internStringCacheExpireDuration duration
+     The expiry duration for caches for interned strings. See https://en.wikipedia.org/wiki/String_interning . See also -internStringMaxLen and -internStringDisableCache (default 6m0s)
+  -internStringDisableCache
+     Whether to disable caches for interned strings. This may reduce memory usage at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning . See also -internStringCacheExpireDuration and -internStringMaxLen
   -internStringMaxLen int
-     The maximum length for strings to intern. Lower limit may save memory at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning (default 300)
+     The maximum length for strings to intern. A lower limit may save memory at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning . See also -internStringDisableCache and -internStringCacheExpireDuration (default 500)
   -kafka.consumer.topic array
      Kafka topic names for data consumption. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
      Supports an array of values separated by comma or specified via multiple flags.
@@ -1225,6 +1310,9 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -kafka.consumer.topic.brokers array
      List of brokers to connect for given topic, e.g. -kafka.consumer.topic.broker=host-1:9092;host-2:9092 . This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
      Supports an array of values separated by comma or specified via multiple flags.
+  -kafka.consumer.topic.concurrency array
+     Configures consumer concurrency for topic specified via -kafka.consumer.topic flag.This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
+     Supports array of values separated by comma or specified via multiple flags.
   -kafka.consumer.topic.defaultFormat string
      Expected data format in the topic if -kafka.consumer.topic.format is skipped. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html (default "promremotewrite")
   -kafka.consumer.topic.format array
@@ -1256,23 +1344,23 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -loggerWarnsPerSecondLimit int
      Per-second limit on the number of WARN messages. If more than the given number of warns are emitted per second, then the remaining warns are suppressed. Zero values disable the rate limit
   -maxConcurrentInserts int
-     The maximum number of concurrent insert requests. Default value should work for most cases, since it minimizes the memory usage. The default value can be increased when clients send data over slow networks. See also -insert.maxQueueDuration (default 8)
+     The maximum number of concurrent insert requests. The default value should work for most cases, since it minimizes memory usage. The default value can be increased when clients send data over slow networks. See also -insert.maxQueueDuration (default 8)
   -maxInsertRequestSize size
      The maximum size in bytes of a single Prometheus remote_write API request
      Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 33554432)
   -memory.allowedBytes size
-     Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to a non-zero value. Too low a value may increase the cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache resulting in higher disk IO usage
+     Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to a non-zero value. Too low a value may increase the cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from the OS page cache resulting in higher disk IO usage
      Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 0)
   -memory.allowedPercent float
-     Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low a value may increase cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from OS page cache which will result in higher disk IO usage (default 60)
+     Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low a value may increase cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from the OS page cache which will result in higher disk IO usage (default 60)
   -metricsAuthKey string
      Auth key for /metrics endpoint. It must be passed via authKey query arg. It overrides httpAuth.* settings
   -opentsdbHTTPListenAddr string
-     TCP address to listen for OpentTSDB HTTP put requests. Usually :4242 must be set. Doesn't work if empty. See also -opentsdbHTTPListenAddr.useProxyProtocol
+     TCP address to listen for OpenTSDB HTTP put requests. Usually :4242 must be set. Doesn't work if empty. See also -opentsdbHTTPListenAddr.useProxyProtocol
   -opentsdbHTTPListenAddr.useProxyProtocol
      Whether to use proxy protocol for connections accepted at -opentsdbHTTPListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
   -opentsdbListenAddr string
-     TCP and UDP address to listen for OpentTSDB metrics. Telnet put messages and HTTP /api/put messages are simultaneously served on TCP port. Usually :4242 must be set. Doesn't work if empty. See also -opentsdbListenAddr.useProxyProtocol
+     TCP and UDP address to listen for OpenTSDB metrics. Telnet put messages and HTTP /api/put messages are simultaneously served on TCP port. Usually :4242 must be set. Doesn't work if empty. See also -opentsdbListenAddr.useProxyProtocol
   -opentsdbListenAddr.useProxyProtocol
      Whether to use proxy protocol for connections accepted at -opentsdbListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
   -opentsdbTrimTimestamp duration
@@ -1289,9 +1377,9 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -promscrape.azureSDCheckInterval duration
      Interval for checking for changes in Azure. This works only if azure_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#azure_sd_configs for details (default 1m0s)
   -promscrape.cluster.memberNum string
-     The number of number in the cluster of scrapers. It must be an unique value in the range 0 ... promscrape.cluster.membersCount-1 across scrapers in the cluster. Can be specified as pod name of Kubernetes StatefulSet - pod-name-Num, where Num is a numeric part of pod name (default "0")
+     The number of number in the cluster of scrapers. It must be a unique value in the range 0 ... promscrape.cluster.membersCount-1 across scrapers in the cluster. Can be specified as pod name of Kubernetes StatefulSet - pod-name-Num, where Num is a numeric part of pod name (default "0")
   -promscrape.cluster.membersCount int
-     The number of members in a cluster of scrapers. Each member must have an unique -promscrape.cluster.memberNum in the range 0 ... promscrape.cluster.membersCount-1 . Each member then scrapes roughly 1/N of all the targets. By default cluster scraping is disabled, i.e. a single scraper scrapes all the targets
+     The number of members in a cluster of scrapers. Each member must have a unique -promscrape.cluster.memberNum in the range 0 ... promscrape.cluster.membersCount-1 . Each member then scrapes roughly 1/N of all the targets. By default, cluster scraping is disabled, i.e. a single scraper scrapes all the targets
   -promscrape.cluster.name string
      Optional name of the cluster. If multiple vmagent clusters scrape the same targets, then each cluster must have unique name in order to properly de-duplicate samples received from these clusters. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2679
   -promscrape.cluster.replicationFactor int
@@ -1303,17 +1391,19 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -promscrape.config.strictParse
      Whether to deny unsupported fields in -promscrape.config . Set to false in order to silently skip unsupported fields (default true)
   -promscrape.configCheckInterval duration
-     Interval for checking for changes in '-promscrape.config' file. By default the checking is disabled. Send SIGHUP signal in order to force config check for changes
+     Interval for checking for changes in '-promscrape.config' file. By default, the checking is disabled. Send SIGHUP signal in order to force config check for changes
   -promscrape.consul.waitTime duration
      Wait time used by Consul service discovery. Default value is used if not set
   -promscrape.consulSDCheckInterval duration
      Interval for checking for changes in Consul. This works only if consul_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#consul_sd_configs for details (default 30s)
+  -promscrape.consulagentSDCheckInterval duration
+     Interval for checking for changes in Consul Agent. This works only if consulagent_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#consulagent_sd_configs for details (default 30s)
   -promscrape.digitaloceanSDCheckInterval duration
      Interval for checking for changes in digital ocean. This works only if digitalocean_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#digitalocean_sd_configs for details (default 1m0s)
   -promscrape.disableCompression
-     Whether to disable sending 'Accept-Encoding: gzip' request headers to all the scrape targets. This may reduce CPU usage on scrape targets at the cost of higher network bandwidth utilization. It is possible to set 'disable_compression: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control
+     Whether to disable sending 'Accept-Encoding: gzip' request headers to all the scrape targets. This may reduce CPU usage on scrape targets at the cost of higher network bandwidth utilization. It is possible to set 'disable_compression: true' individually per each 'scrape_config' section in '-promscrape.config' for fine-grained control
   -promscrape.disableKeepAlive
-     Whether to disable HTTP keep-alive connections when scraping all the targets. This may be useful when targets has no support for HTTP keep-alive connection. It is possible to set 'disable_keepalive: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control. Note that disabling HTTP keep-alive may increase load on both vmagent and scrape targets
+     Whether to disable HTTP keep-alive connections when scraping all the targets. This may be useful when targets has no support for HTTP keep-alive connection. It is possible to set 'disable_keepalive: true' individually per each 'scrape_config' section in '-promscrape.config' for fine-grained control. Note that disabling HTTP keep-alive may increase load on both vmagent and scrape targets
   -promscrape.discovery.concurrency int
      The maximum number of concurrent requests to Prometheus autodiscovery API (Consul, Kubernetes, etc.) (default 100)
   -promscrape.discovery.concurrentWaitTime duration
@@ -1340,6 +1430,8 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
      How frequently to reload the full state from Kubernetes API server (default 30m0s)
   -promscrape.kubernetesSDCheckInterval duration
      Interval for checking for changes in Kubernetes API server. This works only if kubernetes_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#kubernetes_sd_configs for details (default 30s)
+  -promscrape.kumaSDCheckInterval duration
+     Interval for checking for changes in kuma service discovery. This works only if kuma_sd_configs is configured in '-promscrape.config' file. See https://docs.victoriametrics.com/sd_configs.html#kuma_sd_configs for details (default 30s)
   -promscrape.maxDroppedTargets int
      The maximum number of droppedTargets to show at /api/v1/targets page. Increase this value if your setup drops more scrape targets during relabeling and you need investigating labels for all the dropped targets. Note that the increased number of tracked dropped targets may result in increased memory usage (default 1000)
   -promscrape.maxResponseHeadersSize size
@@ -1362,7 +1454,7 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -promscrape.seriesLimitPerTarget int
      Optional limit on the number of unique time series a single scrape target can expose. See https://docs.victoriametrics.com/vmagent.html#cardinality-limiter for more info
   -promscrape.streamParse
-     Whether to enable stream parsing for metrics obtained from scrape targets. This may be useful for reducing memory usage when millions of metrics are exposed per each scrape target. It is posible to set 'stream_parse: true' individually per each 'scrape_config' section in '-promscrape.config' for fine grained control
+     Whether to enable stream parsing for metrics obtained from scrape targets. This may be useful for reducing memory usage when millions of metrics are exposed per each scrape target. It is possible to set 'stream_parse: true' individually per each 'scrape_config' section in '-promscrape.config' for fine-grained control
   -promscrape.suppressDuplicateScrapeTargetErrors
      Whether to suppress 'duplicate scrape target' errors; see https://docs.victoriametrics.com/vmagent.html#troubleshooting for details
   -promscrape.suppressScrapeErrors
@@ -1377,7 +1469,7 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -pushmetrics.interval duration
      Interval for pushing metrics to -pushmetrics.url (default 10s)
   -pushmetrics.url array
-     Optional URL to push metrics exposed at /metrics page. See https://docs.victoriametrics.com/#push-metrics . By default metrics exposed at /metrics page aren't pushed to any remote storage
+     Optional URL to push metrics exposed at /metrics page. See https://docs.victoriametrics.com/#push-metrics . By default, metrics exposed at /metrics page aren't pushed to any remote storage
      Supports an array of values separated by comma or specified via multiple flags.
   -remoteWrite.aws.accessKey array
      Optional AWS AccessKey to use for the corresponding -remoteWrite.url if -remoteWrite.aws.useSigv4 is set
@@ -1420,9 +1512,17 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
      Supports an array of values separated by comma or specified via multiple flags.
   -remoteWrite.flushInterval duration
      Interval for flushing the data to remote storage. This option takes effect only when less than 10K data points per second are pushed to -remoteWrite.url (default 1s)
+  -remoteWrite.forcePromProto array
+     Whether to force Prometheus remote write protocol for sending data to the corresponding -remoteWrite.url . See https://docs.victoriametrics.com/vmagent.html#victoriametrics-remote-write-protocol
+     Supports array of values separated by comma or specified via multiple flags.
+  -remoteWrite.forceVMProto array
+     Whether to force VictoriaMetrics remote write protocol for sending data to the corresponding -remoteWrite.url . See https://docs.victoriametrics.com/vmagent.html#victoriametrics-remote-write-protocol
+     Supports array of values separated by comma or specified via multiple flags.
   -remoteWrite.headers array
      Optional HTTP headers to send with each request to the corresponding -remoteWrite.url. For example, -remoteWrite.headers='My-Auth:foobar' would send 'My-Auth: foobar' HTTP header with every request to the corresponding -remoteWrite.url. Multiple headers must be delimited by '^^': -remoteWrite.headers='header1:value1^^header2:value2'
      Supports an array of values separated by comma or specified via multiple flags.
+  -remoteWrite.keepDanglingQueues
+     Keep persistent queues contents at -remoteWrite.tmpDataPath in case there are no matching -remoteWrite.url. Useful when -remoteWrite.url is changed temporarily and persistent queue files will be needed later on.
   -remoteWrite.label array
      Optional label in the form 'name=value' to add to all the metrics before sending them to -remoteWrite.url. Pass multiple -remoteWrite.label flags in order to add multiple labels to metrics before sending them to remote storage
      Supports an array of values separated by comma or specified via multiple flags.
@@ -1432,7 +1532,7 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -remoteWrite.maxDailySeries int
      The maximum number of unique series vmagent can send to remote storage systems during the last 24 hours. Excess series are logged and dropped. This can be useful for limiting series churn rate. See https://docs.victoriametrics.com/vmagent.html#cardinality-limiter
   -remoteWrite.maxDiskUsagePerURL array
-     The maximum file-based buffer size in bytes at -remoteWrite.tmpDataPath for each -remoteWrite.url. When buffer size reaches the configured maximum, then old data is dropped when adding new data to the buffer. Buffered data is stored in ~500MB chunks, so the minimum practical value for this flag is 500MB. Disk usage is unlimited if the value is set to 0
+     The maximum file-based buffer size in bytes at -remoteWrite.tmpDataPath for each -remoteWrite.url. When buffer size reaches the configured maximum, then old data is dropped when adding new data to the buffer. Buffered data is stored in ~500MB chunks. It is recommended to set the value for this flag to a multiple of the block size 500MB. Disk usage is unlimited if the value is set to 0
      Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB.
      Supports array of values separated by comma or specified via multiple flags.
   -remoteWrite.maxHourlySeries int
@@ -1463,32 +1563,37 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
   -remoteWrite.queues int
      The number of concurrent queues to each -remoteWrite.url. Set more queues if default number of queues isn't enough for sending high volume of collected data to remote storage. Default value is 2 * numberOfAvailableCPUs (default 8)
   -remoteWrite.rateLimit array
-     Optional rate limit in bytes per second for data sent to the corresponding -remoteWrite.url. By default the rate limit is disabled. It can be useful for limiting load on remote storage when big amounts of buffered data is sent after temporary unavailability of the remote storage
+     Optional rate limit in bytes per second for data sent to the corresponding -remoteWrite.url. By default, the rate limit is disabled. It can be useful for limiting load on remote storage when big amounts of buffered data is sent after temporary unavailability of the remote storage
      Supports array of values separated by comma or specified via multiple flags.
   -remoteWrite.relabelConfig string
      Optional path to file with relabeling configs, which are applied to all the metrics before sending them to -remoteWrite.url. See also -remoteWrite.urlRelabelConfig. The path can point either to local file or to http url. See https://docs.victoriametrics.com/vmagent.html#relabeling
   -remoteWrite.roundDigits array
-     Round metric values to this number of decimal digits after the point before writing them to remote storage. Examples: -remoteWrite.roundDigits=2 would round 1.236 to 1.24, while -remoteWrite.roundDigits=-1 would round 126.78 to 130. By default digits rounding is disabled. Set it to 100 for disabling it for a particular remote storage. This option may be used for improving data compression for the stored metrics
+     Round metric values to this number of decimal digits after the point before writing them to remote storage. Examples: -remoteWrite.roundDigits=2 would round 1.236 to 1.24, while -remoteWrite.roundDigits=-1 would round 126.78 to 130. By default, digits rounding is disabled. Set it to 100 for disabling it for a particular remote storage. This option may be used for improving data compression for the stored metrics
      Supports array of values separated by comma or specified via multiple flags.
   -remoteWrite.sendTimeout array
      Timeout for sending a single block of data to the corresponding -remoteWrite.url
      Supports array of values separated by comma or specified via multiple flags.
+  -remoteWrite.shardByURL
+     Whether to shard outgoing series across all the remote storage systems enumerated via -remoteWrite.url . By default the data is replicated across all the -remoteWrite.url . See https://docs.victoriametrics.com/vmagent.html#sharding-among-remote-storages
   -remoteWrite.showURL
      Whether to show -remoteWrite.url in the exported metrics. It is hidden by default, since it can contain sensitive info such as auth key
   -remoteWrite.significantFigures array
      The number of significant figures to leave in metric values before writing them to remote storage. See https://en.wikipedia.org/wiki/Significant_figures . Zero value saves all the significant figures. This option may be used for improving data compression for the stored metrics. See also -remoteWrite.roundDigits
      Supports array of values separated by comma or specified via multiple flags.
   -remoteWrite.streamAggr.config array
-     Optional path to file with stream aggregation config. See https://docs.victoriametrics.com/stream-aggregation.html . See also -remoteWrite.streamAggr.keepInput and -remoteWrite.streamAggr.dedupInterval
+     Optional path to file with stream aggregation config. See https://docs.victoriametrics.com/stream-aggregation.html . See also -remoteWrite.streamAggr.keepInput, -remoteWrite.streamAggr.dropInput and -remoteWrite.streamAggr.dedupInterval
      Supports an array of values separated by comma or specified via multiple flags.
   -remoteWrite.streamAggr.dedupInterval array
      Input samples are de-duplicated with this interval before being aggregated. Only the last sample per each time series per each interval is aggregated if the interval is greater than zero
      Supports array of values separated by comma or specified via multiple flags.
+  -remoteWrite.streamAggr.dropInput array
+     Whether to drop all the input samples after the aggregation with -remoteWrite.streamAggr.config. By default, only aggregates samples are dropped, while the remaining samples are written to the corresponding -remoteWrite.url . See also -remoteWrite.streamAggr.keepInput and https://docs.victoriametrics.com/stream-aggregation.html
+     Supports array of values separated by comma or specified via multiple flags.
   -remoteWrite.streamAggr.keepInput array
-     Whether to keep input samples after the aggregation with -remoteWrite.streamAggr.config. By default the input is dropped after the aggregation, so only the aggregate data is sent to the -remoteWrite.url. See https://docs.victoriametrics.com/stream-aggregation.html
+     Whether to keep all the input samples after the aggregation with -remoteWrite.streamAggr.config. By default, only aggregates samples are dropped, while the remaining samples are written to the corresponding -remoteWrite.url . See also -remoteWrite.streamAggr.dropInput and https://docs.victoriametrics.com/stream-aggregation.html
      Supports array of values separated by comma or specified via multiple flags.
   -remoteWrite.tlsCAFile array
-     Optional path to TLS CA file to use for verifying connections to the corresponding -remoteWrite.url. By default system CA is used
+     Optional path to TLS CA file to use for verifying connections to the corresponding -remoteWrite.url. By default, system CA is used
      Supports an array of values separated by comma or specified via multiple flags.
   -remoteWrite.tlsCertFile array
      Optional path to client-side TLS certificate file to use when connecting to the corresponding -remoteWrite.url
@@ -1500,16 +1605,18 @@ See the docs at https://docs.victoriametrics.com/vmagent.html .
      Optional path to client-side TLS certificate key to use when connecting to the corresponding -remoteWrite.url
      Supports an array of values separated by comma or specified via multiple flags.
   -remoteWrite.tlsServerName array
-     Optional TLS server name to use for connections to the corresponding -remoteWrite.url. By default the server name from -remoteWrite.url is used
+     Optional TLS server name to use for connections to the corresponding -remoteWrite.url. By default, the server name from -remoteWrite.url is used
      Supports an array of values separated by comma or specified via multiple flags.
   -remoteWrite.tmpDataPath string
      Path to directory where temporary data for remote write component is stored. See also -remoteWrite.maxDiskUsagePerURL (default "vmagent-remotewrite-data")
   -remoteWrite.url array
-     Remote storage URL to write data to. It must support Prometheus remote_write API. It is recommended using VictoriaMetrics as remote storage. Example url: http://<victoriametrics-host>:8428/api/v1/write . Pass multiple -remoteWrite.url flags in order to replicate data to multiple remote storage systems. See also -remoteWrite.multitenantURL
+     Remote storage URL to write data to. It must support either VictoriaMetrics remote write protocol or Prometheus remote_write protocol. Example url: http://<victoriametrics-host>:8428/api/v1/write . Pass multiple -remoteWrite.url options in order to replicate the collected data to multiple remote storage systems. The data can be sharded among the configured remote storage systems if -remoteWrite.shardByURL flag is set. See also -remoteWrite.multitenantURL
      Supports an array of values separated by comma or specified via multiple flags.
   -remoteWrite.urlRelabelConfig array
      Optional path to relabel configs for the corresponding -remoteWrite.url. See also -remoteWrite.relabelConfig. The path can point either to local file or to http url. See https://docs.victoriametrics.com/vmagent.html#relabeling
      Supports an array of values separated by comma or specified via multiple flags.
+  -remoteWrite.vmProtoCompressLevel int
+     The compression level for VictoriaMetrics remote write protocol. Higher values reduce network traffic at the cost of higher CPU usage. Negative values reduce CPU usage at the cost of increased network traffic. See https://docs.victoriametrics.com/vmagent.html#victoriametrics-remote-write-protocol
   -sortLabels
      Whether to sort labels for incoming samples before writing them to all the configured remote storage systems. This may be needed for reducing memory usage at remote storage when the order of labels in incoming samples is random. For example, if m{k1="v1",k2="v2"} may be sent as m{k2="v2",k1="v1"}Enabled sorting for labels can slow down ingestion performance a bit
   -tls

app/vmagent/csvimport/request_handler.go

@@ -9,6 +9,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	parserCommon "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
 	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/csvimport"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/csvimport/stream"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/tenantmetrics"
 	"github.com/VictoriaMetrics/metrics"
 )
@@ -25,7 +26,7 @@ func InsertHandler(at *auth.Token, req *http.Request) error {
 	if err != nil {
 		return err
 	}
-	return parser.ParseStream(req, func(rows []parser.Row) error {
+	return stream.Parse(req, func(rows []parser.Row) error {
 		return insertRows(at, rows, extraLabels)
 	})
 }

app/vmagent/datadog/request_handler.go

@@ -9,6 +9,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	parserCommon "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
 	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/datadog"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/datadog/stream"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/tenantmetrics"
 	"github.com/VictoriaMetrics/metrics"
 )
@@ -28,7 +29,7 @@ func InsertHandlerForHTTP(at *auth.Token, req *http.Request) error {
 		return err
 	}
 	ce := req.Header.Get("Content-Encoding")
-	return parser.ParseStream(req.Body, ce, func(series []parser.Series) error {
+	return stream.Parse(req.Body, ce, func(series []parser.Series) error {
 		return insertRows(at, series, extraLabels)
 	})
 }

app/vmagent/graphite/request_handler.go

@@ -7,6 +7,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/remotewrite"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/graphite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/graphite/stream"
 	"github.com/VictoriaMetrics/metrics"
 )
 
@@ -19,7 +20,7 @@ var (
 //
 // See https://graphite.readthedocs.io/en/latest/feeding-carbon.html#the-plaintext-protocol
 func InsertHandler(r io.Reader) error {
-	return parser.ParseStream(r, insertRows)
+	return stream.Parse(r, insertRows)
 }
 
 func insertRows(rows []parser.Row) error {

app/vmagent/influx/request_handler.go

@@ -15,13 +15,14 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promrelabel"
 	parserCommon "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
 	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/influx"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/influx/stream"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/tenantmetrics"
 	"github.com/VictoriaMetrics/metrics"
 )
 
 var (
 	measurementFieldSeparator = flag.String("influxMeasurementFieldSeparator", "_", "Separator for '{measurement}{separator}{field_name}' metric name when inserted via InfluxDB line protocol")
-	skipSingleField           = flag.Bool("influxSkipSingleField", false, "Uses '{measurement}' instead of '{measurement}{separator}{field_name}' for metic name if InfluxDB line contains only a single field")
+	skipSingleField           = flag.Bool("influxSkipSingleField", false, "Uses '{measurement}' instead of '{measurement}{separator}{field_name}' for metric name if InfluxDB line contains only a single field")
 	skipMeasurement           = flag.Bool("influxSkipMeasurement", false, "Uses '{field_name}' as a metric name while ignoring '{measurement}' and '-influxMeasurementFieldSeparator'")
 	dbLabel                   = flag.String("influxDBLabel", "db", "Default label for the DB name sent over '?db={db_name}' query parameter")
 )
@@ -36,7 +37,7 @@ var (
 //
 // See https://github.com/influxdata/telegraf/tree/master/plugins/inputs/socket_listener/
 func InsertHandlerForReader(r io.Reader, isGzipped bool) error {
-	return parser.ParseStream(r, isGzipped, "", "", func(db string, rows []parser.Row) error {
+	return stream.Parse(r, isGzipped, "", "", func(db string, rows []parser.Row) error {
 		return insertRows(nil, db, rows, nil)
 	})
 }
@@ -54,7 +55,7 @@ func InsertHandlerForHTTP(at *auth.Token, req *http.Request) error {
 	precision := q.Get("precision")
 	// Read db tag from https://docs.influxdata.com/influxdb/v1.7/tools/api/#write-http-endpoint
 	db := q.Get("db")
-	return parser.ParseStream(req.Body, isGzipped, precision, db, func(db string, rows []parser.Row) error {
+	return stream.Parse(req.Body, isGzipped, precision, db, func(db string, rows []parser.Row) error {
 		return insertRows(at, db, rows, extraLabels)
 	})
 }

app/vmagent/main.go

@@ -16,6 +16,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/graphite"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/influx"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/native"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/opentelemetry"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/opentsdb"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/opentsdbhttp"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/prometheusimport"
@@ -46,7 +47,8 @@ var (
 		"Set this flag to empty value in order to disable listening on any port. This mode may be useful for running multiple vmagent instances on the same server. "+
 		"Note that /targets and /metrics pages aren't available if -httpListenAddr=''. See also -httpListenAddr.useProxyProtocol")
 	useProxyProtocol = flag.Bool("httpListenAddr.useProxyProtocol", false, "Whether to use proxy protocol for connections accepted at -httpListenAddr . "+
-		"See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt")
+		"See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt . "+
+		"With enabled proxy protocol http server cannot serve regular /metrics endpoint. Use -pushmetrics.url for metrics pushing")
 	influxListenAddr = flag.String("influxListenAddr", "", "TCP and UDP address to listen for InfluxDB line protocol data. Usually :8089 must be set. Doesn't work if empty. "+
 		"This flag isn't needed when ingesting data over HTTP - just send it to http://<vmagent>:8429/write . "+
 		"See also -influxListenAddr.useProxyProtocol")
@@ -56,18 +58,18 @@ var (
 		"See also -graphiteListenAddr.useProxyProtocol")
 	graphiteUseProxyProtocol = flag.Bool("graphiteListenAddr.useProxyProtocol", false, "Whether to use proxy protocol for connections accepted at -graphiteListenAddr . "+
 		"See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt")
-	opentsdbListenAddr = flag.String("opentsdbListenAddr", "", "TCP and UDP address to listen for OpentTSDB metrics. "+
+	opentsdbListenAddr = flag.String("opentsdbListenAddr", "", "TCP and UDP address to listen for OpenTSDB metrics. "+
 		"Telnet put messages and HTTP /api/put messages are simultaneously served on TCP port. "+
 		"Usually :4242 must be set. Doesn't work if empty. See also -opentsdbListenAddr.useProxyProtocol")
 	opentsdbUseProxyProtocol = flag.Bool("opentsdbListenAddr.useProxyProtocol", false, "Whether to use proxy protocol for connections accepted at -opentsdbListenAddr . "+
 		"See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt")
-	opentsdbHTTPListenAddr = flag.String("opentsdbHTTPListenAddr", "", "TCP address to listen for OpentTSDB HTTP put requests. Usually :4242 must be set. Doesn't work if empty. "+
+	opentsdbHTTPListenAddr = flag.String("opentsdbHTTPListenAddr", "", "TCP address to listen for OpenTSDB HTTP put requests. Usually :4242 must be set. Doesn't work if empty. "+
 		"See also -opentsdbHTTPListenAddr.useProxyProtocol")
 	opentsdbHTTPUseProxyProtocol = flag.Bool("opentsdbHTTPListenAddr.useProxyProtocol", false, "Whether to use proxy protocol for connections accepted "+
 		"at -opentsdbHTTPListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt")
 	configAuthKey = flag.String("configAuthKey", "", "Authorization key for accessing /config page. It must be passed via authKey query arg")
-	dryRun        = flag.Bool("dryRun", false, "Whether to check only config files without running vmagent. The following files are checked: "+
-		"-promscrape.config, -remoteWrite.relabelConfig, -remoteWrite.urlRelabelConfig . "+
+	dryRun        = flag.Bool("dryRun", false, "Whether to check config files without running vmagent. The following files are checked: "+
+		"-promscrape.config, -remoteWrite.relabelConfig, -remoteWrite.urlRelabelConfig, -remoteWrite.streamAggr.config . "+
 		"Unknown config entries aren't allowed in -promscrape.config by default. This can be changed by passing -promscrape.config.strictParse=false command-line flag")
 )
 
@@ -98,17 +100,20 @@ func main() {
 		if err := promscrape.CheckConfig(); err != nil {
 			logger.Fatalf("error when checking -promscrape.config: %s", err)
 		}
-		logger.Infof("-promscrape.config is ok; exitting with 0 status code")
+		logger.Infof("-promscrape.config is ok; exiting with 0 status code")
 		return
 	}
 	if *dryRun {
-		if err := remotewrite.CheckRelabelConfigs(); err != nil {
-			logger.Fatalf("error when checking relabel configs: %s", err)
-		}
 		if err := promscrape.CheckConfig(); err != nil {
 			logger.Fatalf("error when checking -promscrape.config: %s", err)
 		}
-		logger.Infof("all the configs are ok; exitting with 0 status code")
+		if err := remotewrite.CheckRelabelConfigs(); err != nil {
+			logger.Fatalf("error when checking relabel configs: %s", err)
+		}
+		if err := remotewrite.CheckStreamAggrConfigs(); err != nil {
+			logger.Fatalf("error when checking -remoteWrite.streamAggr.config: %s", err)
+		}
+		logger.Infof("all the configs are ok; exiting with 0 status code")
 		return
 	}
 
@@ -208,7 +213,7 @@ func getAuthTokenFromPath(path string) (*auth.Token, error) {
 
 func requestHandler(w http.ResponseWriter, r *http.Request) bool {
 	if r.URL.Path == "/" {
-		if r.Method != "GET" {
+		if r.Method != http.MethodGet {
 			return false
 		}
 		w.Header().Add("Content-Type", "text/html; charset=utf-8")
@@ -253,6 +258,9 @@ func requestHandler(w http.ResponseWriter, r *http.Request) bool {
 	}
 	switch path {
 	case "/prometheus/api/v1/write", "/api/v1/write":
+		if common.HandleVMProtoServerHandshake(w, r) {
+			return true
+		}
 		prometheusWriteRequests.Inc()
 		if err := promremotewrite.InsertHandler(nil, r); err != nil {
 			prometheusWriteErrors.Inc()
@@ -301,6 +309,15 @@ func requestHandler(w http.ResponseWriter, r *http.Request) bool {
 		influxQueryRequests.Inc()
 		influxutils.WriteDatabaseNames(w)
 		return true
+	case "/opentelemetry/api/v1/push":
+		opentelemetryPushRequests.Inc()
+		if err := opentelemetry.InsertHandler(nil, r); err != nil {
+			opentelemetryPushErrors.Inc()
+			httpserver.Errorf(w, r, "%s", err)
+			return true
+		}
+		w.WriteHeader(http.StatusOK)
+		return true
 	case "/datadog/api/v1/series":
 		datadogWriteRequests.Inc()
 		if err := datadog.InsertHandlerForHTTP(nil, r); err != nil {
@@ -492,6 +509,15 @@ func processMultitenantRequest(w http.ResponseWriter, r *http.Request, path stri
 		influxQueryRequests.Inc()
 		influxutils.WriteDatabaseNames(w)
 		return true
+	case "opentelemetry/api/v1/push":
+		opentelemetryPushRequests.Inc()
+		if err := opentelemetry.InsertHandler(at, r); err != nil {
+			opentelemetryPushErrors.Inc()
+			httpserver.Errorf(w, r, "%s", err)
+			return true
+		}
+		w.WriteHeader(http.StatusOK)
+		return true
 	case "datadog/api/v1/series":
 		datadogWriteRequests.Inc()
 		if err := datadog.InsertHandlerForHTTP(at, r); err != nil {
@@ -561,6 +587,9 @@ var (
 	datadogIntakeRequests   = metrics.NewCounter(`vmagent_http_requests_total{path="/datadog/intake", protocol="datadog"}`)
 	datadogMetadataRequests = metrics.NewCounter(`vmagent_http_requests_total{path="/datadog/api/v1/metadata", protocol="datadog"}`)
 
+	opentelemetryPushRequests = metrics.NewCounter(`vmagent_http_requests_total{path="/opentelemetry/api/v1/push", protocol="opentelemetry"}`)
+	opentelemetryPushErrors   = metrics.NewCounter(`vmagent_http_request_errors_total{path="/opentelemetry/api/v1/push", protocol="opentelemetry"}`)
+
 	promscrapeTargetsRequests          = metrics.NewCounter(`vmagent_http_requests_total{path="/targets"}`)
 	promscrapeServiceDiscoveryRequests = metrics.NewCounter(`vmagent_http_requests_total{path="/service-discovery"}`)
 

app/vmagent/native/request_handler.go

@@ -10,7 +10,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	parserCommon "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
-	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/native"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/native/stream"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/tenantmetrics"
 	"github.com/VictoriaMetrics/metrics"
 )
@@ -30,12 +30,12 @@ func InsertHandler(at *auth.Token, req *http.Request) error {
 		return err
 	}
 	isGzip := req.Header.Get("Content-Encoding") == "gzip"
-	return parser.ParseStream(req.Body, isGzip, func(block *parser.Block) error {
+	return stream.Parse(req.Body, isGzip, func(block *stream.Block) error {
 		return insertRows(at, block, extraLabels)
 	})
 }
 
-func insertRows(at *auth.Token, block *parser.Block, extraLabels []prompbmarshal.Label) error {
+func insertRows(at *auth.Token, block *stream.Block, extraLabels []prompbmarshal.Label) error {
 	ctx := common.GetPushCtx()
 	defer common.PutPushCtx(ctx)
 

app/vmagent/opentelemetry/request_handler.go

@@ -0,0 +1,65 @@
+package opentelemetry
+
+import (
+	"net/http"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/common"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/remotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/auth"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
+	parserCommon "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/opentelemetry/stream"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/tenantmetrics"
+	"github.com/VictoriaMetrics/metrics"
+)
+
+var (
+	rowsInserted       = metrics.NewCounter(`vmagent_rows_inserted_total{type="opentelemetry"}`)
+	rowsTenantInserted = tenantmetrics.NewCounterMap(`vmagent_tenant_inserted_rows_total{type="opentelemetry"}`)
+	rowsPerInsert      = metrics.NewHistogram(`vmagent_rows_per_insert{type="opentelemetry"}`)
+)
+
+// InsertHandler processes opentelemetry metrics.
+func InsertHandler(at *auth.Token, req *http.Request) error {
+	extraLabels, err := parserCommon.GetExtraLabels(req)
+	if err != nil {
+		return err
+	}
+	isGzipped := req.Header.Get("Content-Encoding") == "gzip"
+	return stream.ParseStream(req.Body, isGzipped, func(tss []prompbmarshal.TimeSeries) error {
+		return insertRows(at, tss, extraLabels)
+	})
+}
+
+func insertRows(at *auth.Token, tss []prompbmarshal.TimeSeries, extraLabels []prompbmarshal.Label) error {
+	ctx := common.GetPushCtx()
+	defer common.PutPushCtx(ctx)
+
+	rowsTotal := 0
+	tssDst := ctx.WriteRequest.Timeseries[:0]
+	labels := ctx.Labels[:0]
+	samples := ctx.Samples[:0]
+	for i := range tss {
+		ts := &tss[i]
+		rowsTotal += len(ts.Samples)
+		labelsLen := len(labels)
+		labels = append(labels, ts.Labels...)
+		labels = append(labels, extraLabels...)
+		samplesLen := len(samples)
+		samples = append(samples, ts.Samples...)
+		tssDst = append(tssDst, prompbmarshal.TimeSeries{
+			Labels:  labels[labelsLen:],
+			Samples: samples[samplesLen:],
+		})
+	}
+	ctx.WriteRequest.Timeseries = tssDst
+	ctx.Labels = labels
+	ctx.Samples = samples
+	remotewrite.Push(at, &ctx.WriteRequest)
+	rowsInserted.Add(rowsTotal)
+	if at != nil {
+		rowsTenantInserted.Get(at).Add(rowsTotal)
+	}
+	rowsPerInsert.Update(float64(rowsTotal))
+	return nil
+}

app/vmagent/opentsdb/request_handler.go

@@ -7,6 +7,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/remotewrite"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/opentsdb"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/opentsdb/stream"
 	"github.com/VictoriaMetrics/metrics"
 )
 
@@ -19,7 +20,7 @@ var (
 //
 // See http://opentsdb.net/docs/build/html/api_telnet/put.html
 func InsertHandler(r io.Reader) error {
-	return parser.ParseStream(r, insertRows)
+	return stream.Parse(r, insertRows)
 }
 
 func insertRows(rows []parser.Row) error {

app/vmagent/opentsdbhttp/request_handler.go

@@ -9,6 +9,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	parserCommon "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
 	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/opentsdbhttp"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/opentsdbhttp/stream"
 	"github.com/VictoriaMetrics/metrics"
 )
 
@@ -24,7 +25,7 @@ func InsertHandler(at *auth.Token, req *http.Request) error {
 	if err != nil {
 		return err
 	}
-	return parser.ParseStream(req, func(rows []parser.Row) error {
+	return stream.Parse(req, func(rows []parser.Row) error {
 		return insertRows(at, rows, extraLabels)
 	})
 }

app/vmagent/prometheusimport/request_handler.go

@@ -10,6 +10,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	parserCommon "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
 	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/prometheus"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/prometheus/stream"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/tenantmetrics"
 	"github.com/VictoriaMetrics/metrics"
 )
@@ -31,7 +32,7 @@ func InsertHandler(at *auth.Token, req *http.Request) error {
 		return err
 	}
 	isGzipped := req.Header.Get("Content-Encoding") == "gzip"
-	return parser.ParseStream(req.Body, defaultTimestamp, isGzipped, func(rows []parser.Row) error {
+	return stream.Parse(req.Body, defaultTimestamp, isGzipped, func(rows []parser.Row) error {
 		return insertRows(at, rows, extraLabels)
 	}, func(s string) {
 		httpserver.LogError(req, s)

app/vmagent/prometheusimport/request_handler_test.go

@@ -23,7 +23,7 @@ var (
 func TestInsertHandler(t *testing.T) {
 	setUp()
 	defer tearDown()
-	req := httptest.NewRequest("POST", "/insert/0/api/v1/import/prometheus", bytes.NewBufferString(`{"foo":"bar"}
+	req := httptest.NewRequest(http.MethodPost, "/insert/0/api/v1/import/prometheus", bytes.NewBufferString(`{"foo":"bar"}
 go_memstats_alloc_bytes_total 1`))
 	if err := InsertHandler(nil, req); err != nil {
 		t.Errorf("unxepected error %s", err)

app/vmagent/promremotewrite/request_handler.go

@@ -10,7 +10,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompb"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	parserCommon "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
-	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/promremotewrite"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/promremotewrite/stream"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/tenantmetrics"
 	"github.com/VictoriaMetrics/metrics"
 )
@@ -27,7 +27,8 @@ func InsertHandler(at *auth.Token, req *http.Request) error {
 	if err != nil {
 		return err
 	}
-	return parser.ParseStream(req.Body, func(tss []prompb.TimeSeries) error {
+	isVMRemoteWrite := req.Header.Get("Content-Encoding") == "zstd"
+	return stream.Parse(req.Body, isVMRemoteWrite, func(tss []prompb.TimeSeries) error {
 		return insertRows(at, tss, extraLabels)
 	})
 }

app/vmagent/remotewrite/client.go

@@ -15,13 +15,19 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/persistentqueue"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promauth"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/timerpool"
 	"github.com/VictoriaMetrics/metrics"
 )
 
 var (
+	forcePromProto = flagutil.NewArrayBool("remoteWrite.forcePromProto", "Whether to force Prometheus remote write protocol for sending data "+
+		"to the corresponding -remoteWrite.url . See https://docs.victoriametrics.com/vmagent.html#victoriametrics-remote-write-protocol")
+	forceVMProto = flagutil.NewArrayBool("remoteWrite.forceVMProto", "Whether to force VictoriaMetrics remote write protocol for sending data "+
+		"to the corresponding -remoteWrite.url . See https://docs.victoriametrics.com/vmagent.html#victoriametrics-remote-write-protocol")
+
 	rateLimit = flagutil.NewArrayInt("remoteWrite.rateLimit", "Optional rate limit in bytes per second for data sent to the corresponding -remoteWrite.url. "+
-		"By default the rate limit is disabled. It can be useful for limiting load on remote storage when big amounts of buffered data "+
+		"By default, the rate limit is disabled. It can be useful for limiting load on remote storage when big amounts of buffered data "+
 		"is sent after temporary unavailability of the remote storage")
 	sendTimeout = flagutil.NewArrayDuration("remoteWrite.sendTimeout", "Timeout for sending a single block of data to the corresponding -remoteWrite.url")
 	proxyURL    = flagutil.NewArrayString("remoteWrite.proxyURL", "Optional proxy URL for writing data to the corresponding -remoteWrite.url. "+
@@ -32,9 +38,9 @@ var (
 		"to the corresponding -remoteWrite.url")
 	tlsKeyFile = flagutil.NewArrayString("remoteWrite.tlsKeyFile", "Optional path to client-side TLS certificate key to use when connecting to the corresponding -remoteWrite.url")
 	tlsCAFile  = flagutil.NewArrayString("remoteWrite.tlsCAFile", "Optional path to TLS CA file to use for verifying connections to the corresponding -remoteWrite.url. "+
-		"By default system CA is used")
+		"By default, system CA is used")
 	tlsServerName = flagutil.NewArrayString("remoteWrite.tlsServerName", "Optional TLS server name to use for connections to the corresponding -remoteWrite.url. "+
-		"By default the server name from -remoteWrite.url is used")
+		"By default, the server name from -remoteWrite.url is used")
 
 	headers = flagutil.NewArrayString("remoteWrite.headers", "Optional HTTP headers to send with each request to the corresponding -remoteWrite.url. "+
 		"For example, -remoteWrite.headers='My-Auth:foobar' would send 'My-Auth: foobar' HTTP header with every request to the corresponding -remoteWrite.url. "+
@@ -69,8 +75,12 @@ var (
 type client struct {
 	sanitizedURL   string
 	remoteWriteURL string
-	fq             *persistentqueue.FastQueue
-	hc             *http.Client
+
+	// Whether to use VictoriaMetrics remote write protocol for sending the data to remoteWriteURL
+	useVMProto bool
+
+	fq *persistentqueue.FastQueue
+	hc *http.Client
 
 	sendBlock func(block []byte) bool
 	authCfg   *promauth.Config
@@ -122,19 +132,39 @@ func newHTTPClient(argIdx int, remoteWriteURL, sanitizedURL string, fq *persiste
 		}
 		tr.Proxy = http.ProxyURL(pu)
 	}
+	hc := &http.Client{
+		Transport: tr,
+		Timeout:   sendTimeout.GetOptionalArgOrDefault(argIdx, time.Minute),
+	}
 	c := &client{
 		sanitizedURL:   sanitizedURL,
 		remoteWriteURL: remoteWriteURL,
 		authCfg:        authCfg,
 		awsCfg:         awsCfg,
 		fq:             fq,
-		hc: &http.Client{
-			Transport: tr,
-			Timeout:   sendTimeout.GetOptionalArgOrDefault(argIdx, time.Minute),
-		},
-		stopCh: make(chan struct{}),
+		hc:             hc,
+		stopCh:         make(chan struct{}),
 	}
 	c.sendBlock = c.sendBlockHTTP
+
+	useVMProto := forceVMProto.GetOptionalArg(argIdx)
+	usePromProto := forcePromProto.GetOptionalArg(argIdx)
+	if useVMProto && usePromProto {
+		logger.Fatalf("-remoteWrite.useVMProto and -remoteWrite.usePromProto cannot be set simultaneously for -remoteWrite.url=%s", sanitizedURL)
+	}
+	if !useVMProto && !usePromProto {
+		// Auto-detect whether the remote storage supports VictoriaMetrics remote write protocol.
+		doRequest := func(url string) (*http.Response, error) {
+			return c.doRequest(url, nil)
+		}
+		useVMProto = common.HandleVMProtoClientHandshake(c.remoteWriteURL, doRequest)
+		if !useVMProto {
+			logger.Infof("the remote storage at %q doesn't support VictoriaMetrics remote write protocol. Switching to Prometheus remote write protocol. "+
+				"See https://docs.victoriametrics.com/vmagent.html#victoriametrics-remote-write-protocol", sanitizedURL)
+		}
+	}
+	c.useVMProto = useVMProto
+
 	return c
 }
 
@@ -227,7 +257,7 @@ func getAuthConfig(argIdx int) (*promauth.Config, error) {
 	}
 	authCfg, err := opts.NewConfig()
 	if err != nil {
-		return nil, fmt.Errorf("cannot populate OAuth2 config for remoteWrite idx: %d, err: %w", argIdx, err)
+		return nil, fmt.Errorf("cannot populate auth config for remoteWrite idx: %d, err: %w", argIdx, err)
 	}
 	return authCfg, nil
 }
@@ -291,38 +321,45 @@ func (c *client) runWorker() {
 	}
 }
 
-// sendBlockHTTP returns false only if c.stopCh is closed.
-// Otherwise it tries sending the block to remote storage indefinitely.
-func (c *client) sendBlockHTTP(block []byte) bool {
-	c.rl.register(len(block), c.stopCh)
-	retryDuration := time.Second
-	retriesCount := 0
-	c.bytesSent.Add(len(block))
-	c.blocksSent.Inc()
-	sigv4Hash := ""
-	if c.awsCfg != nil {
-		sigv4Hash = awsapi.HashHex(block)
-	}
-
-again:
-	req, err := http.NewRequest("POST", c.remoteWriteURL, bytes.NewBuffer(block))
+func (c *client) doRequest(url string, body []byte) (*http.Response, error) {
+	reqBody := bytes.NewBuffer(body)
+	req, err := http.NewRequest(http.MethodPost, url, reqBody)
 	if err != nil {
-		logger.Panicf("BUG: unexpected error from http.NewRequest(%q): %s", c.sanitizedURL, err)
+		logger.Panicf("BUG: unexpected error from http.NewRequest(%q): %s", url, err)
 	}
 	c.authCfg.SetHeaders(req, true)
 	h := req.Header
 	h.Set("User-Agent", "vmagent")
 	h.Set("Content-Type", "application/x-protobuf")
-	h.Set("Content-Encoding", "snappy")
-	h.Set("X-Prometheus-Remote-Write-Version", "0.1.0")
+	if c.useVMProto {
+		h.Set("Content-Encoding", "zstd")
+		h.Set("X-VictoriaMetrics-Remote-Write-Version", "1")
+	} else {
+		h.Set("Content-Encoding", "snappy")
+		h.Set("X-Prometheus-Remote-Write-Version", "0.1.0")
+	}
 	if c.awsCfg != nil {
+		sigv4Hash := awsapi.HashHex(body)
 		if err := c.awsCfg.SignRequest(req, sigv4Hash); err != nil {
 			// there is no need in retry, request will be rejected by client.Do and retried by code below
 			logger.Warnf("cannot sign remoteWrite request with AWS sigv4: %s", err)
 		}
 	}
+	return c.hc.Do(req)
+}
+
+// sendBlockHTTP sends the given block to c.remoteWriteURL.
+//
+// The function returns false only if c.stopCh is closed.
+// Otherwise it tries sending the block to remote storage indefinitely.
+func (c *client) sendBlockHTTP(block []byte) bool {
+	c.rl.register(len(block), c.stopCh)
+	retryDuration := time.Second
+	retriesCount := 0
+
+again:
 	startTime := time.Now()
-	resp, err := c.hc.Do(req)
+	resp, err := c.doRequest(c.remoteWriteURL, block)
 	c.requestDuration.UpdateDuration(startTime)
 	if err != nil {
 		c.errorsCount.Inc()
@@ -347,6 +384,8 @@ again:
 	if statusCode/100 == 2 {
 		_ = resp.Body.Close()
 		c.requestsOKCount.Inc()
+		c.bytesSent.Add(len(block))
+		c.blocksSent.Inc()
 		return true
 	}
 	metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_remotewrite_requests_total{url=%q, status_code="%d"}`, c.sanitizedURL, statusCode)).Inc()

app/vmagent/remotewrite/pendingseries.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/decimal"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding/zstd"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/fasttime"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
@@ -23,6 +24,9 @@ var (
 		"This option takes effect only when less than 10K data points per second are pushed to -remoteWrite.url")
 	maxUnpackedBlockSize = flagutil.NewBytes("remoteWrite.maxBlockSize", 8*1024*1024, "The maximum block size to send to remote storage. Bigger blocks may improve performance at the cost of the increased memory usage. See also -remoteWrite.maxRowsPerBlock")
 	maxRowsPerBlock      = flag.Int("remoteWrite.maxRowsPerBlock", 10000, "The maximum number of samples to send in each block to remote storage. Higher number may improve performance at the cost of the increased memory usage. See also -remoteWrite.maxBlockSize")
+	vmProtoCompressLevel = flag.Int("remoteWrite.vmProtoCompressLevel", 0, "The compression level for VictoriaMetrics remote write protocol. "+
+		"Higher values reduce network traffic at the cost of higher CPU usage. Negative values reduce CPU usage at the cost of increased network traffic. "+
+		"See https://docs.victoriametrics.com/vmagent.html#victoriametrics-remote-write-protocol")
 )
 
 type pendingSeries struct {
@@ -33,9 +37,10 @@ type pendingSeries struct {
 	periodicFlusherWG sync.WaitGroup
 }
 
-func newPendingSeries(pushBlock func(block []byte), significantFigures, roundDigits int) *pendingSeries {
+func newPendingSeries(pushBlock func(block []byte), isVMRemoteWrite bool, significantFigures, roundDigits int) *pendingSeries {
 	var ps pendingSeries
 	ps.wr.pushBlock = pushBlock
+	ps.wr.isVMRemoteWrite = isVMRemoteWrite
 	ps.wr.significantFigures = significantFigures
 	ps.wr.roundDigits = roundDigits
 	ps.stopCh = make(chan struct{})
@@ -88,6 +93,9 @@ type writeRequest struct {
 	// pushBlock is called when whe write request is ready to be sent.
 	pushBlock func(block []byte)
 
+	// Whether to encode the write request with VictoriaMetrics remote write protocol.
+	isVMRemoteWrite bool
+
 	// How many significant figures must be left before sending the writeRequest to pushBlock.
 	significantFigures int
 
@@ -104,7 +112,7 @@ type writeRequest struct {
 }
 
 func (wr *writeRequest) reset() {
-	// Do not reset pushBlock, significantFigures and roundDigits, since they are re-used.
+	// Do not reset lastFlushTime, pushBlock, isVMRemoteWrite, significantFigures and roundDigits, since they are re-used.
 
 	wr.wr.Timeseries = nil
 
@@ -126,7 +134,7 @@ func (wr *writeRequest) flush() {
 	wr.wr.Timeseries = wr.tss
 	wr.adjustSampleValues()
 	atomic.StoreUint64(&wr.lastFlushTime, fasttime.UnixTimestamp())
-	pushWriteRequest(&wr.wr, wr.pushBlock)
+	pushWriteRequest(&wr.wr, wr.pushBlock, wr.isVMRemoteWrite)
 	wr.reset()
 }
 
@@ -188,7 +196,7 @@ func (wr *writeRequest) copyTimeSeries(dst, src *prompbmarshal.TimeSeries) {
 	wr.buf = buf
 }
 
-func pushWriteRequest(wr *prompbmarshal.WriteRequest, pushBlock func(block []byte)) {
+func pushWriteRequest(wr *prompbmarshal.WriteRequest, pushBlock func(block []byte), isVMRemoteWrite bool) {
 	if len(wr.Timeseries) == 0 {
 		// Nothing to push
 		return
@@ -197,7 +205,11 @@ func pushWriteRequest(wr *prompbmarshal.WriteRequest, pushBlock func(block []byt
 	bb.B = prompbmarshal.MarshalWriteRequest(bb.B[:0], wr)
 	if len(bb.B) <= maxUnpackedBlockSize.IntN() {
 		zb := snappyBufPool.Get()
-		zb.B = snappy.Encode(zb.B[:cap(zb.B)], bb.B)
+		if isVMRemoteWrite {
+			zb.B = zstd.CompressLevel(zb.B[:0], bb.B, *vmProtoCompressLevel)
+		} else {
+			zb.B = snappy.Encode(zb.B[:cap(zb.B)], bb.B)
+		}
 		writeRequestBufPool.Put(bb)
 		if len(zb.B) <= persistentqueue.MaxBlockSize {
 			pushBlock(zb.B)
@@ -221,18 +233,18 @@ func pushWriteRequest(wr *prompbmarshal.WriteRequest, pushBlock func(block []byt
 		}
 		n := len(samples) / 2
 		wr.Timeseries[0].Samples = samples[:n]
-		pushWriteRequest(wr, pushBlock)
+		pushWriteRequest(wr, pushBlock, isVMRemoteWrite)
 		wr.Timeseries[0].Samples = samples[n:]
-		pushWriteRequest(wr, pushBlock)
+		pushWriteRequest(wr, pushBlock, isVMRemoteWrite)
 		wr.Timeseries[0].Samples = samples
 		return
 	}
 	timeseries := wr.Timeseries
 	n := len(timeseries) / 2
 	wr.Timeseries = timeseries[:n]
-	pushWriteRequest(wr, pushBlock)
+	pushWriteRequest(wr, pushBlock, isVMRemoteWrite)
 	wr.Timeseries = timeseries[n:]
-	pushWriteRequest(wr, pushBlock)
+	pushWriteRequest(wr, pushBlock, isVMRemoteWrite)
 	wr.Timeseries = timeseries
 }
 

app/vmagent/remotewrite/pendingseries_test.go

@@ -2,40 +2,48 @@ package remotewrite
 
 import (
 	"fmt"
+	"math"
 	"testing"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
-	"github.com/golang/snappy"
 )
 
 func TestPushWriteRequest(t *testing.T) {
-	for _, rowsCount := range []int{1, 10, 100, 1e3, 1e4} {
+	rowsCounts := []int{1, 10, 100, 1e3, 1e4}
+	expectedBlockLensProm := []int{216, 1848, 16424, 169882, 1757876}
+	expectedBlockLensVM := []int{138, 492, 3927, 34995, 288476}
+	for i, rowsCount := range rowsCounts {
+		expectedBlockLenProm := expectedBlockLensProm[i]
+		expectedBlockLenVM := expectedBlockLensVM[i]
 		t.Run(fmt.Sprintf("%d", rowsCount), func(t *testing.T) {
-			testPushWriteRequest(t, rowsCount)
+			testPushWriteRequest(t, rowsCount, expectedBlockLenProm, expectedBlockLenVM)
 		})
 	}
 }
 
-func testPushWriteRequest(t *testing.T, rowsCount int) {
-	wr := newTestWriteRequest(rowsCount, 10)
-	pushBlockLen := 0
-	pushBlock := func(block []byte) {
-		if pushBlockLen > 0 {
-			panic(fmt.Errorf("BUG: pushBlock called multiple times; pushBlockLen=%d at first call, len(block)=%d at second call", pushBlockLen, len(block)))
+func testPushWriteRequest(t *testing.T, rowsCount, expectedBlockLenProm, expectedBlockLenVM int) {
+	f := func(isVMRemoteWrite bool, expectedBlockLen int, tolerancePrc float64) {
+		t.Helper()
+		wr := newTestWriteRequest(rowsCount, 20)
+		pushBlockLen := 0
+		pushBlock := func(block []byte) {
+			if pushBlockLen > 0 {
+				panic(fmt.Errorf("BUG: pushBlock called multiple times; pushBlockLen=%d at first call, len(block)=%d at second call", pushBlockLen, len(block)))
+			}
+			pushBlockLen = len(block)
+		}
+		pushWriteRequest(wr, pushBlock, isVMRemoteWrite)
+		if math.Abs(float64(pushBlockLen-expectedBlockLen)/float64(expectedBlockLen)*100) > tolerancePrc {
+			t.Fatalf("unexpected block len for rowsCount=%d, isVMRemoteWrite=%v; got %d bytes; expecting %d bytes +- %.0f%%",
+				rowsCount, isVMRemoteWrite, pushBlockLen, expectedBlockLen, tolerancePrc)
 		}
-		pushBlockLen = len(block)
-	}
-	pushWriteRequest(wr, pushBlock)
-	b := prompbmarshal.MarshalWriteRequest(nil, wr)
-	zb := snappy.Encode(nil, b)
-	maxPushBlockLen := len(zb)
-	minPushBlockLen := maxPushBlockLen / 2
-	if pushBlockLen < minPushBlockLen {
-		t.Fatalf("unexpected block len after pushWriteRequest; got %d bytes; must be at least %d bytes", pushBlockLen, minPushBlockLen)
-	}
-	if pushBlockLen > maxPushBlockLen {
-		t.Fatalf("unexpected block len after pushWriteRequest; got %d bytes; must be smaller or equal to %d bytes", pushBlockLen, maxPushBlockLen)
 	}
+
+	// Check Prometheus remote write
+	f(false, expectedBlockLenProm, 0)
+
+	// Check VictoriaMetrics remote write
+	f(true, expectedBlockLenVM, 15)
 }
 
 func newTestWriteRequest(seriesCount, labelsCount int) *prompbmarshal.WriteRequest {

app/vmagent/remotewrite/remotewrite.go

@@ -4,17 +4,21 @@ import (
 	"flag"
 	"fmt"
 	"net/url"
+	"path/filepath"
 	"strconv"
 	"sync"
 	"sync/atomic"
 	"time"
 
+	"github.com/cespare/xxhash/v2"
+
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/auth"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bloomfilter"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/fasttime"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/fs"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/memory"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/persistentqueue"
@@ -24,32 +28,37 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/streamaggr"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/tenantmetrics"
 	"github.com/VictoriaMetrics/metrics"
-	"github.com/cespare/xxhash/v2"
 )
 
 var (
-	remoteWriteURLs = flagutil.NewArrayString("remoteWrite.url", "Remote storage URL to write data to. It must support Prometheus remote_write API. "+
-		"It is recommended using VictoriaMetrics as remote storage. Example url: http://<victoriametrics-host>:8428/api/v1/write . "+
-		"Pass multiple -remoteWrite.url flags in order to replicate data to multiple remote storage systems. See also -remoteWrite.multitenantURL")
+	remoteWriteURLs = flagutil.NewArrayString("remoteWrite.url", "Remote storage URL to write data to. It must support either VictoriaMetrics remote write protocol "+
+		"or Prometheus remote_write protocol. Example url: http://<victoriametrics-host>:8428/api/v1/write . "+
+		"Pass multiple -remoteWrite.url options in order to replicate the collected data to multiple remote storage systems. "+
+		"The data can be sharded among the configured remote storage systems if -remoteWrite.shardByURL flag is set. "+
+		"See also -remoteWrite.multitenantURL")
 	remoteWriteMultitenantURLs = flagutil.NewArrayString("remoteWrite.multitenantURL", "Base path for multitenant remote storage URL to write data to. "+
 		"See https://docs.victoriametrics.com/vmagent.html#multitenancy for details. Example url: http://<vminsert>:8480 . "+
 		"Pass multiple -remoteWrite.multitenantURL flags in order to replicate data to multiple remote storage systems. See also -remoteWrite.url")
+	shardByURL = flag.Bool("remoteWrite.shardByURL", false, "Whether to shard outgoing series across all the remote storage systems enumerated via -remoteWrite.url . "+
+		"By default the data is replicated across all the -remoteWrite.url . See https://docs.victoriametrics.com/vmagent.html#sharding-among-remote-storages")
 	tmpDataPath = flag.String("remoteWrite.tmpDataPath", "vmagent-remotewrite-data", "Path to directory where temporary data for remote write component is stored. "+
 		"See also -remoteWrite.maxDiskUsagePerURL")
+	keepDanglingQueues = flag.Bool("remoteWrite.keepDanglingQueues", false, "Keep persistent queues contents at -remoteWrite.tmpDataPath in case there are no matching -remoteWrite.url. "+
+		"Useful when -remoteWrite.url is changed temporarily and persistent queue files will be needed later on.")
 	queues = flag.Int("remoteWrite.queues", cgroup.AvailableCPUs()*2, "The number of concurrent queues to each -remoteWrite.url. Set more queues if default number of queues "+
 		"isn't enough for sending high volume of collected data to remote storage. Default value is 2 * numberOfAvailableCPUs")
 	showRemoteWriteURL = flag.Bool("remoteWrite.showURL", false, "Whether to show -remoteWrite.url in the exported metrics. "+
 		"It is hidden by default, since it can contain sensitive info such as auth key")
 	maxPendingBytesPerURL = flagutil.NewArrayBytes("remoteWrite.maxDiskUsagePerURL", "The maximum file-based buffer size in bytes at -remoteWrite.tmpDataPath "+
 		"for each -remoteWrite.url. When buffer size reaches the configured maximum, then old data is dropped when adding new data to the buffer. "+
-		"Buffered data is stored in ~500MB chunks, so the minimum practical value for this flag is 500MB. "+
+		"Buffered data is stored in ~500MB chunks. It is recommended to set the value for this flag to a multiple of the block size 500MB. "+
 		"Disk usage is unlimited if the value is set to 0")
 	significantFigures = flagutil.NewArrayInt("remoteWrite.significantFigures", "The number of significant figures to leave in metric values before writing them "+
 		"to remote storage. See https://en.wikipedia.org/wiki/Significant_figures . Zero value saves all the significant figures. "+
 		"This option may be used for improving data compression for the stored metrics. See also -remoteWrite.roundDigits")
 	roundDigits = flagutil.NewArrayInt("remoteWrite.roundDigits", "Round metric values to this number of decimal digits after the point before writing them to remote storage. "+
 		"Examples: -remoteWrite.roundDigits=2 would round 1.236 to 1.24, while -remoteWrite.roundDigits=-1 would round 126.78 to 130. "+
-		"By default digits rounding is disabled. Set it to 100 for disabling it for a particular remote storage. "+
+		"By default, digits rounding is disabled. Set it to 100 for disabling it for a particular remote storage. "+
 		"This option may be used for improving data compression for the stored metrics")
 	sortLabels = flag.Bool("sortLabels", false, `Whether to sort labels for incoming samples before writing them to all the configured remote storage systems. `+
 		`This may be needed for reducing memory usage at remote storage when the order of labels in incoming samples is random. `+
@@ -62,10 +71,13 @@ var (
 
 	streamAggrConfig = flagutil.NewArrayString("remoteWrite.streamAggr.config", "Optional path to file with stream aggregation config. "+
 		"See https://docs.victoriametrics.com/stream-aggregation.html . "+
-		"See also -remoteWrite.streamAggr.keepInput and -remoteWrite.streamAggr.dedupInterval")
-	streamAggrKeepInput = flagutil.NewArrayBool("remoteWrite.streamAggr.keepInput", "Whether to keep input samples after the aggregation with -remoteWrite.streamAggr.config. "+
-		"By default the input is dropped after the aggregation, so only the aggregate data is sent to the -remoteWrite.url. "+
-		"See https://docs.victoriametrics.com/stream-aggregation.html")
+		"See also -remoteWrite.streamAggr.keepInput, -remoteWrite.streamAggr.dropInput and -remoteWrite.streamAggr.dedupInterval")
+	streamAggrKeepInput = flagutil.NewArrayBool("remoteWrite.streamAggr.keepInput", "Whether to keep all the input samples after the aggregation "+
+		"with -remoteWrite.streamAggr.config. By default, only aggregates samples are dropped, while the remaining samples "+
+		"are written to the corresponding -remoteWrite.url . See also -remoteWrite.streamAggr.dropInput and https://docs.victoriametrics.com/stream-aggregation.html")
+	streamAggrDropInput = flagutil.NewArrayBool("remoteWrite.streamAggr.dropInput", "Whether to drop all the input samples after the aggregation "+
+		"with -remoteWrite.streamAggr.config. By default, only aggregates samples are dropped, while the remaining samples "+
+		"are written to the corresponding -remoteWrite.url . See also -remoteWrite.streamAggr.keepInput and https://docs.victoriametrics.com/stream-aggregation.html")
 	streamAggrDedupInterval = flagutil.NewArrayDuration("remoteWrite.streamAggr.dedupInterval", "Input samples are de-duplicated with this interval before being aggregated. "+
 		"Only the last sample per each time series per each interval is aggregated if the interval is greater than zero")
 )
@@ -88,12 +100,14 @@ func MultitenancyEnabled() bool {
 }
 
 // Contains the current relabelConfigs.
-var allRelabelConfigs atomic.Value
+var allRelabelConfigs atomic.Pointer[relabelConfigs]
 
 // maxQueues limits the maximum value for `-remoteWrite.queues`. There is no sense in setting too high value,
 // since it may lead to high memory usage due to big number of buffers.
 var maxQueues = cgroup.AvailableCPUs() * 16
 
+const persistentQueueDirname = "persistent-queue"
+
 // InitSecretFlags must be called after flag.Parse and before any logging.
 func InitSecretFlags() {
 	if !*showRemoteWriteURL {
@@ -150,9 +164,8 @@ func Init() {
 		logger.Fatalf("cannot load relabel configs: %s", err)
 	}
 	allRelabelConfigs.Store(rcs)
-
-	configSuccess.Set(1)
-	configTimestamp.Set(fasttime.UnixTimestamp())
+	relabelConfigSuccess.Set(1)
+	relabelConfigTimestamp.Set(fasttime.UnixTimestamp())
 
 	if len(*remoteWriteURLs) > 0 {
 		rwctxsDefault = newRemoteWriteCtxs(nil, *remoteWriteURLs)
@@ -165,34 +178,56 @@ func Init() {
 		for {
 			select {
 			case <-sighupCh:
-			case <-stopCh:
+			case <-configReloaderStopCh:
 				return
 			}
-			configReloads.Inc()
-			logger.Infof("SIGHUP received; reloading relabel configs pointed by -remoteWrite.relabelConfig and -remoteWrite.urlRelabelConfig")
-			rcs, err := loadRelabelConfigs()
-			if err != nil {
-				configReloadErrors.Inc()
-				configSuccess.Set(0)
-				logger.Errorf("cannot reload relabel configs; preserving the previous configs; error: %s", err)
-				continue
-			}
-
-			allRelabelConfigs.Store(rcs)
-			configSuccess.Set(1)
-			configTimestamp.Set(fasttime.UnixTimestamp())
-			logger.Infof("Successfully reloaded relabel configs")
+			reloadRelabelConfigs()
+			reloadStreamAggrConfigs()
 		}
 	}()
 }
 
+func reloadRelabelConfigs() {
+	relabelConfigReloads.Inc()
+	logger.Infof("reloading relabel configs pointed by -remoteWrite.relabelConfig and -remoteWrite.urlRelabelConfig")
+	rcs, err := loadRelabelConfigs()
+	if err != nil {
+		relabelConfigReloadErrors.Inc()
+		relabelConfigSuccess.Set(0)
+		logger.Errorf("cannot reload relabel configs; preserving the previous configs; error: %s", err)
+		return
+	}
+	allRelabelConfigs.Store(rcs)
+	relabelConfigSuccess.Set(1)
+	relabelConfigTimestamp.Set(fasttime.UnixTimestamp())
+	logger.Infof("successfully reloaded relabel configs")
+}
+
 var (
-	configReloads      = metrics.NewCounter(`vmagent_relabel_config_reloads_total`)
-	configReloadErrors = metrics.NewCounter(`vmagent_relabel_config_reloads_errors_total`)
-	configSuccess      = metrics.NewCounter(`vmagent_relabel_config_last_reload_successful`)
-	configTimestamp    = metrics.NewCounter(`vmagent_relabel_config_last_reload_success_timestamp_seconds`)
+	relabelConfigReloads      = metrics.NewCounter(`vmagent_relabel_config_reloads_total`)
+	relabelConfigReloadErrors = metrics.NewCounter(`vmagent_relabel_config_reloads_errors_total`)
+	relabelConfigSuccess      = metrics.NewCounter(`vmagent_relabel_config_last_reload_successful`)
+	relabelConfigTimestamp    = metrics.NewCounter(`vmagent_relabel_config_last_reload_success_timestamp_seconds`)
 )
 
+func reloadStreamAggrConfigs() {
+	if len(*remoteWriteMultitenantURLs) > 0 {
+		rwctxsMapLock.Lock()
+		for _, rwctxs := range rwctxsMap {
+			reinitStreamAggr(rwctxs)
+		}
+		rwctxsMapLock.Unlock()
+	} else {
+		reinitStreamAggr(rwctxsDefault)
+	}
+}
+
+func reinitStreamAggr(rwctxs []*remoteWriteCtx) {
+	for _, rwctx := range rwctxs {
+		rwctx.reinitStreamAggr()
+	}
+}
+
 func newRemoteWriteCtxs(at *auth.Token, urls []string) []*remoteWriteCtx {
 	if len(urls) == 0 {
 		logger.Panicf("BUG: urls must be non-empty")
@@ -225,17 +260,44 @@ func newRemoteWriteCtxs(at *auth.Token, urls []string) []*remoteWriteCtx {
 		}
 		rwctxs[i] = newRemoteWriteCtx(i, at, remoteWriteURL, maxInmemoryBlocks, sanitizedURL)
 	}
+
+	if !*keepDanglingQueues {
+		// Remove dangling queues, if any.
+		// This is required for the case when the number of queues has been changed or URL have been changed.
+		// See: https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4014
+		existingQueues := make(map[string]struct{}, len(rwctxs))
+		for _, rwctx := range rwctxs {
+			existingQueues[rwctx.fq.Dirname()] = struct{}{}
+		}
+
+		queuesDir := filepath.Join(*tmpDataPath, persistentQueueDirname)
+		files := fs.MustReadDir(queuesDir)
+		removed := 0
+		for _, f := range files {
+			dirname := f.Name()
+			if _, ok := existingQueues[dirname]; !ok {
+				logger.Infof("removing dangling queue %q", dirname)
+				fullPath := filepath.Join(queuesDir, dirname)
+				fs.MustRemoveAll(fullPath)
+				removed++
+			}
+		}
+		if removed > 0 {
+			logger.Infof("removed %d dangling queues from %q, active queues: %d", removed, *tmpDataPath, len(rwctxs))
+		}
+	}
+
 	return rwctxs
 }
 
-var stopCh = make(chan struct{})
+var configReloaderStopCh = make(chan struct{})
 var configReloaderWG sync.WaitGroup
 
 // Stop stops remotewrite.
 //
 // It is expected that nobody calls Push during and after the call to this func.
 func Stop() {
-	close(stopCh)
+	close(configReloaderStopCh)
 	configReloaderWG.Wait()
 
 	for _, rwctx := range rwctxsDefault {
@@ -264,7 +326,7 @@ func Stop() {
 // If at is nil, then the data is pushed to the configured `-remoteWrite.url`.
 // If at isn't nil, the data is pushed to the configured `-remoteWrite.multitenantURL`.
 //
-// Note that wr may be modified by Push due to relabeling and rounding.
+// Note that wr may be modified by Push because of relabeling and rounding.
 func Push(at *auth.Token, wr *prompbmarshal.WriteRequest) {
 	if at == nil && len(*remoteWriteMultitenantURLs) > 0 {
 		// Write data to default tenant if at isn't set while -remoteWrite.multitenantURL is set.
@@ -291,7 +353,7 @@ func Push(at *auth.Token, wr *prompbmarshal.WriteRequest) {
 	}
 
 	var rctx *relabelCtx
-	rcs := allRelabelConfigs.Load().(*relabelConfigs)
+	rcs := allRelabelConfigs.Load()
 	pcsGlobal := rcs.global
 	if pcsGlobal.Len() > 0 || len(labelsGlobal) > 0 {
 		rctx = getRelabelCtx()
@@ -345,10 +407,46 @@ func pushBlockToRemoteStorages(rwctxs []*remoteWriteCtx, tssBlock []prompbmarsha
 		// Nothing to push
 		return
 	}
-	// Push block to remote storages in parallel in order to reduce the time needed for sending the data to multiple remote storage systems.
+	if len(rwctxs) == 1 {
+		// Fast path - just push data to the configured single remote storage
+		rwctxs[0].Push(tssBlock)
+		return
+	}
+
+	// We need to push tssBlock to multiple remote storages.
+	// This is either sharding or replication depending on -remoteWrite.shardByURL command-line flag value.
+	if *shardByURL {
+		// Shard the data among rwctxs
+		tssByURL := make([][]prompbmarshal.TimeSeries, len(rwctxs))
+		for _, ts := range tssBlock {
+			h := getLabelsHash(ts.Labels)
+			idx := h % uint64(len(tssByURL))
+			tssByURL[idx] = append(tssByURL[idx], ts)
+		}
+		// Push sharded data to remote storages in parallel in order to reduce
+		// the time needed for sending the data to multiple remote storage systems.
+		var wg sync.WaitGroup
+		wg.Add(len(rwctxs))
+		for i, rwctx := range rwctxs {
+			tssShard := tssByURL[i]
+			if len(tssShard) == 0 {
+				continue
+			}
+			go func(rwctx *remoteWriteCtx, tss []prompbmarshal.TimeSeries) {
+				defer wg.Done()
+				rwctx.Push(tss)
+			}(rwctx, tssShard)
+		}
+		wg.Wait()
+		return
+	}
+
+	// Replicate data among rwctxs.
+	// Push block to remote storages in parallel in order to reduce
+	// the time needed for sending the data to multiple remote storage systems.
 	var wg sync.WaitGroup
+	wg.Add(len(rwctxs))
 	for _, rwctx := range rwctxs {
-		wg.Add(1)
 		go func(rwctx *remoteWriteCtx) {
 			defer wg.Done()
 			rwctx.Push(tssBlock)
@@ -450,8 +548,9 @@ type remoteWriteCtx struct {
 	fq  *persistentqueue.FastQueue
 	c   *client
 
-	sas                 *streamaggr.Aggregators
+	sas                 atomic.Pointer[streamaggr.Aggregators]
 	streamAggrKeepInput bool
+	streamAggrDropInput bool
 
 	pss        []*pendingSeries
 	pssNextIdx uint64
@@ -466,8 +565,13 @@ func newRemoteWriteCtx(argIdx int, at *auth.Token, remoteWriteURL *url.URL, maxI
 	pqURL.RawQuery = ""
 	pqURL.Fragment = ""
 	h := xxhash.Sum64([]byte(pqURL.String()))
-	queuePath := fmt.Sprintf("%s/persistent-queue/%d_%016X", *tmpDataPath, argIdx+1, h)
+	queuePath := filepath.Join(*tmpDataPath, persistentQueueDirname, fmt.Sprintf("%d_%016X", argIdx+1, h))
 	maxPendingBytes := maxPendingBytesPerURL.GetOptionalArgOrDefault(argIdx, 0)
+	if maxPendingBytes != 0 && maxPendingBytes < persistentqueue.DefaultChunkFileSize {
+		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4195
+		logger.Warnf("rounding the -remoteWrite.maxDiskUsagePerURL=%d to the minimum supported value: %d", maxPendingBytes, persistentqueue.DefaultChunkFileSize)
+		maxPendingBytes = persistentqueue.DefaultChunkFileSize
+	}
 	fq := persistentqueue.MustOpenFastQueue(queuePath, sanitizedURL, maxInmemoryBlocks, maxPendingBytes)
 	_ = metrics.GetOrCreateGauge(fmt.Sprintf(`vmagent_remotewrite_pending_data_bytes{path=%q, url=%q}`, queuePath, sanitizedURL), func() float64 {
 		return float64(fq.GetPendingBytes())
@@ -475,6 +579,7 @@ func newRemoteWriteCtx(argIdx int, at *auth.Token, remoteWriteURL *url.URL, maxI
 	_ = metrics.GetOrCreateGauge(fmt.Sprintf(`vmagent_remotewrite_pending_inmemory_blocks{path=%q, url=%q}`, queuePath, sanitizedURL), func() float64 {
 		return float64(fq.GetInmemoryQueueLen())
 	})
+
 	var c *client
 	switch remoteWriteURL.Scheme {
 	case "http", "https":
@@ -495,7 +600,7 @@ func newRemoteWriteCtx(argIdx int, at *auth.Token, remoteWriteURL *url.URL, maxI
 	}
 	pss := make([]*pendingSeries, pssLen)
 	for i := range pss {
-		pss[i] = newPendingSeries(fq.MustWriteBlock, sf, rd)
+		pss[i] = newPendingSeries(fq.MustWriteBlock, c.useVMProto, sf, rd)
 	}
 
 	rwctx := &remoteWriteCtx{
@@ -514,16 +619,24 @@ func newRemoteWriteCtx(argIdx int, at *auth.Token, remoteWriteURL *url.URL, maxI
 		dedupInterval := streamAggrDedupInterval.GetOptionalArgOrDefault(argIdx, 0)
 		sas, err := streamaggr.LoadFromFile(sasFile, rwctx.pushInternal, dedupInterval)
 		if err != nil {
-			logger.Fatalf("cannot initialize stream aggregators from -remoteWrite.streamAggrFile=%q: %s", sasFile, err)
+			logger.Fatalf("cannot initialize stream aggregators from -remoteWrite.streamAggr.config=%q: %s", sasFile, err)
 		}
-		rwctx.sas = sas
+		rwctx.sas.Store(sas)
 		rwctx.streamAggrKeepInput = streamAggrKeepInput.GetOptionalArg(argIdx)
+		rwctx.streamAggrDropInput = streamAggrDropInput.GetOptionalArg(argIdx)
+		metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_streamaggr_config_reload_successful{path=%q}`, sasFile)).Set(1)
+		metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_streamaggr_config_reload_success_timestamp_seconds{path=%q}`, sasFile)).Set(fasttime.UnixTimestamp())
 	}
 
 	return rwctx
 }
 
 func (rwctx *remoteWriteCtx) MustStop() {
+	// sas must be stopped before rwctx is closed
+	// because sas can write pending series to rwctx.pss if there are any
+	sas := rwctx.sas.Swap(nil)
+	sas.MustStop()
+
 	for _, ps := range rwctx.pss {
 		ps.MustStop()
 	}
@@ -532,8 +645,7 @@ func (rwctx *remoteWriteCtx) MustStop() {
 	rwctx.fq.UnblockAllReaders()
 	rwctx.c.MustStop()
 	rwctx.c = nil
-	rwctx.sas.MustStop()
-	rwctx.sas = nil
+
 	rwctx.fq.MustClose()
 	rwctx.fq = nil
 
@@ -545,7 +657,7 @@ func (rwctx *remoteWriteCtx) Push(tss []prompbmarshal.TimeSeries) {
 	// Apply relabeling
 	var rctx *relabelCtx
 	var v *[]prompbmarshal.TimeSeries
-	rcs := allRelabelConfigs.Load().(*relabelConfigs)
+	rcs := allRelabelConfigs.Load()
 	pcs := rcs.perURL[rwctx.idx]
 	if pcs.Len() > 0 {
 		rctx = getRelabelCtx()
@@ -553,7 +665,7 @@ func (rwctx *remoteWriteCtx) Push(tss []prompbmarshal.TimeSeries) {
 		// from affecting time series for other remoteWrite.url configs.
 		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/467
 		// and https://github.com/VictoriaMetrics/VictoriaMetrics/issues/599
-		v = tssRelabelPool.Get().(*[]prompbmarshal.TimeSeries)
+		v = tssPool.Get().(*[]prompbmarshal.TimeSeries)
 		tss = append(*v, tss...)
 		rowsCountBeforeRelabel := getRowsCount(tss)
 		tss = rctx.applyRelabeling(tss, nil, pcs)
@@ -564,27 +676,83 @@ func (rwctx *remoteWriteCtx) Push(tss []prompbmarshal.TimeSeries) {
 	rwctx.rowsPushedAfterRelabel.Add(rowsCount)
 
 	// Apply stream aggregation if any
-	rwctx.sas.Push(tss)
-	if rwctx.sas == nil || rwctx.streamAggrKeepInput {
-		// Push samples to the remote storage
-		rwctx.pushInternal(tss)
+	sas := rwctx.sas.Load()
+	if sas != nil {
+		matchIdxs := matchIdxsPool.Get()
+		matchIdxs.B = sas.Push(tss, matchIdxs.B)
+		if !rwctx.streamAggrKeepInput {
+			if rctx == nil {
+				rctx = getRelabelCtx()
+				// Make a copy of tss before dropping aggregated series
+				v = tssPool.Get().(*[]prompbmarshal.TimeSeries)
+				tss = append(*v, tss...)
+			}
+			tss = dropAggregatedSeries(tss, matchIdxs.B, rwctx.streamAggrDropInput)
+		}
+		matchIdxsPool.Put(matchIdxs)
 	}
+	rwctx.pushInternal(tss)
 
 	// Return back relabeling contexts to the pool
 	if rctx != nil {
 		*v = prompbmarshal.ResetTimeSeries(tss)
-		tssRelabelPool.Put(v)
+		tssPool.Put(v)
 		putRelabelCtx(rctx)
 	}
 }
 
+var matchIdxsPool bytesutil.ByteBufferPool
+
+func dropAggregatedSeries(src []prompbmarshal.TimeSeries, matchIdxs []byte, dropInput bool) []prompbmarshal.TimeSeries {
+	dst := src[:0]
+	for i, match := range matchIdxs {
+		if match == 0 {
+			continue
+		}
+		dst = append(dst, src[i])
+	}
+	tail := src[len(dst):]
+	_ = prompbmarshal.ResetTimeSeries(tail)
+	return dst
+}
+
 func (rwctx *remoteWriteCtx) pushInternal(tss []prompbmarshal.TimeSeries) {
 	pss := rwctx.pss
 	idx := atomic.AddUint64(&rwctx.pssNextIdx, 1) % uint64(len(pss))
 	pss[idx].Push(tss)
 }
 
-var tssRelabelPool = &sync.Pool{
+func (rwctx *remoteWriteCtx) reinitStreamAggr() {
+	sas := rwctx.sas.Load()
+	if sas == nil {
+		// There is no stream aggregation for rwctx
+		return
+	}
+
+	sasFile := streamAggrConfig.GetOptionalArg(rwctx.idx)
+	logger.Infof("reloading stream aggregation configs pointed by -remoteWrite.streamAggr.config=%q", sasFile)
+	metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_streamaggr_config_reloads_total{path=%q}`, sasFile)).Inc()
+	dedupInterval := streamAggrDedupInterval.GetOptionalArgOrDefault(rwctx.idx, 0)
+	sasNew, err := streamaggr.LoadFromFile(sasFile, rwctx.pushInternal, dedupInterval)
+	if err != nil {
+		metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_streamaggr_config_reloads_errors_total{path=%q}`, sasFile)).Inc()
+		metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_streamaggr_config_reload_successful{path=%q}`, sasFile)).Set(0)
+		logger.Errorf("cannot reload stream aggregation config from -remoteWrite.streamAggr.config=%q; continue using the previously loaded config; error: %s", sasFile, err)
+		return
+	}
+	if !sasNew.Equal(sas) {
+		sasOld := rwctx.sas.Swap(sasNew)
+		sasOld.MustStop()
+		logger.Infof("successfully reloaded stream aggregation configs at -remoteWrite.streamAggr.config=%q", sasFile)
+	} else {
+		sasNew.MustStop()
+		logger.Infof("the config at -remoteWrite.streamAggr.config=%q wasn't changed", sasFile)
+	}
+	metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_streamaggr_config_reload_successful{path=%q}`, sasFile)).Set(1)
+	metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_streamaggr_config_reload_success_timestamp_seconds{path=%q}`, sasFile)).Set(fasttime.UnixTimestamp())
+}
+
+var tssPool = &sync.Pool{
 	New: func() interface{} {
 		a := []prompbmarshal.TimeSeries{}
 		return &a
@@ -598,3 +766,20 @@ func getRowsCount(tss []prompbmarshal.TimeSeries) int {
 	}
 	return rowsCount
 }
+
+// CheckStreamAggrConfigs checks configs pointed by -remoteWrite.streamAggr.config
+func CheckStreamAggrConfigs() error {
+	pushNoop := func(tss []prompbmarshal.TimeSeries) {}
+	for idx, sasFile := range *streamAggrConfig {
+		if sasFile == "" {
+			continue
+		}
+		dedupInterval := streamAggrDedupInterval.GetOptionalArgOrDefault(idx, 0)
+		sas, err := streamaggr.LoadFromFile(sasFile, pushNoop, dedupInterval)
+		if err != nil {
+			return fmt.Errorf("cannot load -remoteWrite.streamAggr.config=%q: %w", sasFile, err)
+		}
+		sas.MustStop()
+	}
+	return nil
+}

app/vmagent/vmimport/request_handler.go

@@ -11,6 +11,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
 	parserCommon "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/common"
 	parser "github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/vmimport"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/protoparser/vmimport/stream"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/tenantmetrics"
 	"github.com/VictoriaMetrics/metrics"
 )
@@ -30,7 +31,7 @@ func InsertHandler(at *auth.Token, req *http.Request) error {
 		return err
 	}
 	isGzipped := req.Header.Get("Content-Encoding") == "gzip"
-	return parser.ParseStream(req.Body, isGzipped, func(rows []parser.Row) error {
+	return stream.Parse(req.Body, isGzipped, func(rows []parser.Row) error {
 		return insertRows(at, rows, extraLabels)
 	})
 }

app/vmalert/Makefile

@@ -73,6 +73,8 @@ test-vmalert:
 	go test -v -race -cover ./app/vmalert/notifier
 	go test -v -race -cover ./app/vmalert/config
 	go test -v -race -cover ./app/vmalert/remotewrite
+	go test -v -race -cover ./app/vmalert/utils
+	go test -v -race -cover ./app/vmalert/unittest
 
 run-vmalert: vmalert
 	./bin/vmalert -rule=app/vmalert/config/testdata/rules/rules2-good.rules \
@@ -102,6 +104,10 @@ replay-vmalert: vmalert
 		-replay.timeFrom=2021-05-11T07:21:43Z \
 		-replay.timeTo=2021-05-29T18:40:43Z
 
+unittest-vmalert: vmalert
+	./bin/vmalert -unittestFile=app/vmalert/unittest/testdata/test1.yaml \
+ 		-unittestFile=app/vmalert/unittest/testdata/test2.yaml
+
 vmalert-linux-amd64:
 	APP_NAME=vmalert CGO_ENABLED=1 GOOS=linux GOARCH=amd64 $(MAKE) app-local-goos-goarch
 
@@ -114,6 +120,9 @@ vmalert-linux-arm64:
 vmalert-linux-ppc64le:
 	APP_NAME=vmalert CGO_ENABLED=0 GOOS=linux GOARCH=ppc64le $(MAKE) app-local-goos-goarch
 
+vmalert-linux-s390x:
+	APP_NAME=vmalert CGO_ENABLED=0 GOOS=linux GOARCH=s390x $(MAKE) app-local-goos-goarch
+
 vmalert-linux-386:
 	APP_NAME=vmalert CGO_ENABLED=0 GOOS=linux GOARCH=386 $(MAKE) app-local-goos-goarch
 

app/vmalert/README.md

@@ -14,7 +14,7 @@ or [cluster version](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.ht
 of VictoriaMetrics are capable of proxying requests to vmalert via `-vmalert.proxyURL` command-line flag. 
 Use this feature for the following cases:
 * for proxying requests from [Grafana Alerting UI](https://grafana.com/docs/grafana/latest/alerting/);
-* for accessing vmalert's UI through VictoriaMetrics Web interface.
+* for accessing vmalerts UI through VictoriaMetrics Web interface.
 
 ## Features
 
@@ -23,12 +23,14 @@ Use this feature for the following cases:
   support and expressions validation;
 * Prometheus [alerting rules definition format](https://prometheus.io/docs/prometheus/latest/configuration/alerting_rules/#defining-alerting-rules)
   support;
-* Integration with [Alertmanager](https://github.com/prometheus/alertmanager) starting from [Alertmanager v0.16.0-aplha](https://github.com/prometheus/alertmanager/releases/tag/v0.16.0-alpha.0);
+* Integration with [Alertmanager](https://github.com/prometheus/alertmanager) starting from [Alertmanager v0.16.0-alpha](https://github.com/prometheus/alertmanager/releases/tag/v0.16.0-alpha.0);
 * Keeps the alerts [state on restarts](#alerts-state-on-restarts);
 * Graphite datasource can be used for alerting and recording rules. See [these docs](#graphite);
 * Recording and Alerting rules backfilling (aka `replay`). See [these docs](#rules-backfilling);
 * Lightweight and without extra dependencies.
-* Supports [reusable templates](#reusable-templates) for annotations.
+* Supports [reusable templates](#reusable-templates) for annotations;
+* Load of recording and alerting rules from local filesystem, URL, GCS and S3;
+* Detect alerting rules which [don't match any series](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4039).
 
 ## Limitations
 
@@ -143,6 +145,15 @@ params:
 headers:
   [ <string>, ...]
 
+# Optional list of HTTP headers in form `header-name: value`
+# applied for all alert notifications sent to notifiers 
+# generated by rules of this group.
+# For example:
+#  notifier_headers:
+#    - "TenantID: foo"
+notifier_headers:
+        [ <string>, ...]
+
 # Optional list of labels added to every rule within a group.
 # It has priority over the external labels.
 # Labels are commonly used for adding environment
@@ -192,16 +203,22 @@ expr: <string>
 # as firing once they return.
 [ for: <duration> | default = 0s ]
 
+# Alert will continue firing for this long even when the alerting expression no longer has results.
+# This allows you to delay alert resolution.
+[ keep_firing_for: <duration> | default = 0s ]
+
 # Whether to print debug information into logs.
 # Information includes alerts state changes and requests sent to the datasource.
 # Please note, that if rule's query params contain sensitive
 # information - it will be printed to logs.
 # Is applicable to alerting rules only.
+# Available starting from https://docs.victoriametrics.com/CHANGELOG.html#v1820
 [ debug: <bool> | default = false ]
 
 # Defines the number of rule's updates entries stored in memory
 # and available for view on rule's Details page.
 # Overrides `rule.updateEntriesLimit` value for this specific rule.
+# Available starting from https://docs.victoriametrics.com/CHANGELOG.html#v1860
 [ update_entries_limit: <integer> | default 0 ]
 
 # Labels to add or overwrite for each alert.
@@ -260,7 +277,7 @@ Additionally, `vmalert` provides some extra templating functions listed [here](#
   query at `-datasource.url` and returns the first result.
 - `queryEscape` - escapes the input string, so it can be safely put inside [query arg](https://en.wikipedia.org/wiki/Percent-encoding) part of URL.
 - `quotesEscape` - escapes the input string, so it can be safely embedded into JSON string.
-- `reReplaceAll regex repl` - replaces all the occurences of the `regex` in input string with the `repl`.
+- `reReplaceAll regex repl` - replaces all the occurrences of the `regex` in input string with the `repl`.
 - `safeHtml` - marks the input string as safe to use in HTML context without the need to html-escape it.
 - `sortByLabel name` - sorts the input query results by the label with the given `name`.
 - `stripDomain` - leaves the first part of the domain. For example, `foo.bar.baz` is converted to `foo`.
@@ -344,19 +361,24 @@ For recording rules to work `-remoteWrite.url` must be specified.
 
 ### Alerts state on restarts
 
-`vmalert` has no local storage, so alerts state is stored in the process memory. Hence, after restart of `vmalert`
-the process alerts state will be lost. To avoid this situation, `vmalert` should be configured via the following flags:
+`vmalert` is stateless, it holds alerts state in the process memory. Restarting of `vmalert` process
+will reset alerts state in memory. To prevent `vmalert` from losing alerts state it should be configured
+to persist the state to the remote destination via the following flags:
 
 * `-remoteWrite.url` - URL to VictoriaMetrics (Single) or vminsert (Cluster). `vmalert` will persist alerts state
-  into the configured address in the form of time series named `ALERTS` and `ALERTS_FOR_STATE` via remote-write protocol.
-  These are regular time series and maybe queried from VM just as any other time series.
-  The state is stored to the configured address on every rule evaluation.
+  to the configured address in the form of [time series](https://docs.victoriametrics.com/keyConcepts.html#time-series)
+  `ALERTS` and `ALERTS_FOR_STATE` via remote-write protocol.
+  These time series can be queried from VictoriaMetrics just as any other time series.
+  The state will be persisted to the configured address on each evaluation.
 * `-remoteRead.url` - URL to VictoriaMetrics (Single) or vmselect (Cluster). `vmalert` will try to restore alerts state
-  from configured address by querying time series with name `ALERTS_FOR_STATE`.
+  from the configured address by querying time series with name `ALERTS_FOR_STATE`. The restore happens only once when
+  `vmalert` process starts, and only for the configured rules. Config [hot reload](#hot-config-reload) doesn't trigger 
+  state restore.
 
 Both flags are required for proper state restoration. Restore process may fail if time series are missing
 in configured `-remoteRead.url`, weren't updated in the last `1h` (controlled by `-remoteRead.lookback`)
-or received state doesn't match current `vmalert` rules configuration.
+or received state doesn't match current `vmalert` rules configuration. `vmalert` marks successfully restored rules
+with `restored` label in [web UI](#WEB).
 
 ### Multitenancy
 
@@ -404,6 +426,25 @@ The enterprise version of vmalert is available in `vmutils-*-enterprise.tar.gz`
 at [release page](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) and in `*-enterprise`
 tags at [Docker Hub](https://hub.docker.com/r/victoriametrics/vmalert/tags).
 
+### Reading rules from object storage
+
+[Enterprise version](https://docs.victoriametrics.com/enterprise.html) of `vmalert` may read alerting and recording rules
+from object storage:
+
+- `./bin/vmalert -rule=s3://bucket/dir/alert.rules` would read rules from the given path at S3 bucket
+- `./bin/vmalert -rule=gs://bucket/bir/alert.rules` would read rules from the given path at GCS bucket
+
+S3 and GCS paths support only matching by prefix, e.g. `s3://bucket/dir/rule_` matches
+all files with prefix `rule_` in the folder `dir`.
+
+The following [command-line flags](#flags) can be used for fine-tuning access to S3 and GCS:
+
+- `-s3.credsFilePath` - path to file with GCS or S3 credentials. Credentials are loaded from default locations if not set.
+- `-s3.configFilePath` - path to file with S3 configs. Configs are loaded from default location if not set.
+- `-s3.configProfile` - profile name for S3 configs. If no set, the value of the environment variable will be loaded (`AWS_PROFILE` or `AWS_DEFAULT_PROFILE`).
+- `-s3.customEndpoint` - custom S3 endpoint for use with S3-compatible storages (e.g. MinIO). S3 is used if not set.
+- `-s3.forcePathStyle` - prefixing endpoint with bucket name when set false, true by default.
+
 ### Topology examples
 
 The following sections are showing how `vmalert` may be used and configured
@@ -453,7 +494,7 @@ Cluster mode could have multiple `vminsert` and `vmselect` components.
 <img alt="vmalert cluster" src="vmalert_cluster.png">
 
 In case when you want to spread the load on these components - add balancers before them and configure
-`vmalert` with balancer's addresses. Please, see more about VM's cluster architecture
+`vmalert` with balancer addresses. Please, see more about VM's cluster architecture
 [here](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#architecture-overview).
 
 #### HA vmalert
@@ -478,7 +519,7 @@ Alertmanagers.
 
 To avoid recording rules results and alerts state duplication in VictoriaMetrics server
 don't forget to configure [deduplication](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html#deduplication).
-The recommended value for `-dedup.minScrapeInterval` must be greater or equal to vmalert's `evaluation_interval`.
+The recommended value for `-dedup.minScrapeInterval` must be greater or equal to vmalert `evaluation_interval`.
 If you observe inconsistent or "jumping" values in series produced by vmalert, try disabling `-datasource.queryTimeAlignment`
 command line flag. Because of alignment, two or more vmalert HA pairs will produce results with the same timestamps.
 But due of backfilling (data delivered to the datasource with some delay) values of such results may differ,
@@ -488,7 +529,7 @@ Alertmanager will automatically deduplicate alerts with identical labels, so ens
 all `vmalert`s are having the same config.
 
 Don't forget to configure [cluster mode](https://prometheus.io/docs/alerting/latest/alertmanager/)
-for Alertmanagers for better reliability. List all Alertmanager URLs in vmalert's `-notifier.url` 
+for Alertmanagers for better reliability. List all Alertmanager URLs in vmalert `-notifier.url`
 to ensure [high availability](https://github.com/prometheus/alertmanager#high-availability).
 
 This example uses single-node VM server for the sake of simplicity.
@@ -496,6 +537,9 @@ Check how to replace it with [cluster VictoriaMetrics](#cluster-victoriametrics)
 
 #### Downsampling and aggregation via vmalert
 
+_Please note, [stream aggregation](https://docs.victoriametrics.com/stream-aggregation.html) might be more efficient
+for cases when downsampling or aggregation need to be applied **before data gets into the TSDB.**_
+
 `vmalert` can't modify existing data. But it can run arbitrary PromQL/MetricsQL queries
 via [recording rules](#recording-rules) and backfill results to the configured `-remoteWrite.url`.
 This ability allows to aggregate data. For example, the following rule will calculate the average value for
@@ -580,7 +624,7 @@ or time series modification via [relabeling](https://docs.victoriametrics.com/vm
 
 `vmalert` web UI can be accessed from [single-node version of VictoriaMetrics](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html)
 and from [cluster version of VictoriaMetrics](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html).
-This may be used for better integraion with Grafana unified alerting system. See the following docs for details:
+This may be used for better integration with Grafana unified alerting system. See the following docs for details:
 
 * [How to query vmalert from single-node VictoriaMetrics](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html#vmalert)
 * [How to query vmalert from VictoriaMetrics cluster](https://docs.victoriametrics.com/Cluster-VictoriaMetrics.html#vmalert)
@@ -601,6 +645,12 @@ can read the same rules configuration as normal, evaluate them on the given time
 results via remote write to the configured storage. vmalert supports any PromQL/MetricsQL compatible
 data source for backfilling.
 
+Please note, that response caching may lead to unexpected results during and after backfilling process.
+In order to avoid this you need to reset cache contents or disable caching when using backfilling
+as described in [backfilling docs](https://docs.victoriametrics.com/Single-server-VictoriaMetrics.html#backfilling).
+
+See a blogpost about [Rules backfilling via vmalert](https://victoriametrics.com/blog/rules-replay/).
+
 ### How it works
 
 In `replay` mode vmalert works as a cli-tool and exits immediately after work is done.
@@ -690,6 +740,250 @@ See full description for these flags in `./vmalert -help`.
 * Graphite engine isn't supported yet;
 * `query` template function is disabled for performance reasons (might be changed in future);
 * `limit` group's param has no effect during replay (might be changed in future);
+* `keep_firing_for` alerting rule param has no effect during replay (might be changed in future).
+
+## Unit Testing for Rules
+
+> Unit testing is available from v1.92.0. 
+> Unit tests do not respect `-clusterMode` for now.
+
+You can use `vmalert` to run unit tests for alerting and recording rules.
+In unit test mode vmalert performs the following actions:
+* sets up an isolated VictoriaMetrics instance;
+* simulates the periodic ingestion of time series;
+* queries the ingested data for recording and alerting rules evaluation;
+* tests whether the firing alerts or resulting recording rules match the expected results. 
+
+See how to run vmalert in unit test mode below:
+```
+# Run vmalert with one or multiple test files via -unittestFile cmd-line flag
+./vmalert -unittestFile=test1.yaml -unittestFile=test2.yaml
+```
+
+vmalert is compatible with [Prometheus config format for tests](https://prometheus.io/docs/prometheus/latest/configuration/unit_testing_rules/#test-file-format)
+except `promql_expr_test` field. Use `metricsql_expr_test` field name instead. The name is different because vmalert 
+validates and executes [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html) expressions, 
+which aren't always backward compatible with [PromQL](https://prometheus.io/docs/prometheus/latest/querying/basics/).
+
+### Test file format
+
+The configuration format for files specified in `-unittestFile` cmd-line flag is the following:
+```
+# Path to the files or http url containing [rule groups](https://docs.victoriametrics.com/vmalert.html#groups) configuration.
+# Enterprise version of vmalert supports S3 and GCS paths to rules.
+rule_files:
+  [ - <string> ]
+
+# The evaluation interval for rules specified in `rule_files`
+[ evaluation_interval: <duration> | default = 1m ]
+
+# Groups listed below will be evaluated by order.
+# Not All the groups need not be mentioned, if not, they will be evaluated by define order in rule_files.
+group_eval_order:
+  [ - <string> ]
+
+# The list of unit test files to be checked during evaluation.
+tests:
+  [ - <test_group> ]
+```
+
+#### `<test_group>`
+
+```
+# Interval between samples for input series
+interval: <duration>
+# Time series to persist into the database according to configured <interval> before running tests.
+input_series:
+  [ - <series> ]
+
+# Name of the test group, optional
+[ name: <string> ]
+
+# Unit tests for alerting rules
+alert_rule_test:
+  [ - <alert_test_case> ]
+
+# Unit tests for Metricsql expressions.
+metricsql_expr_test:
+  [ - <metricsql_expr_test> ]
+
+# External labels accessible for templating.
+external_labels:
+  [ <labelname>: <string> ... ]
+
+```
+
+#### `<series>`
+
+```
+# series in the following format '<metric name>{<label name>=<label value>, ...}'
+# Examples:
+#      series_name{label1="value1", label2="value2"}
+#      go_goroutines{job="prometheus", instance="localhost:9090"}
+series: <string>
+
+# values support several special equations:
+#    'a+bxc' becomes 'a a+b a+(2*b) a+(3*b) … a+(c*b)'
+#     Read this as series starts at a, then c further samples incrementing by b.
+#    'a-bxc' becomes 'a a-b a-(2*b) a-(3*b) … a-(c*b)'
+#     Read this as series starts at a, then c further samples decrementing by b (or incrementing by negative b).
+#    '_' represents a missing sample from scrape
+#    'stale' indicates a stale sample
+# Examples:
+#     1. '-2+4x3' becomes '-2 2 6 10' - series starts at -2, then 3 further samples incrementing by 4.
+#     2. ' 1-2x4' becomes '1 -1 -3 -5 -7' - series starts at 1, then 4 further samples decrementing by 2.
+#     3. ' 1x4' becomes '1 1 1 1 1' - shorthand for '1+0x4', series starts at 1, then 4 further samples incrementing by 0.
+#     4. ' 1 _x3 stale' becomes '1 _ _ _ stale' - the missing sample cannot increment, so 3 missing samples are produced by the '_x3' expression.
+values: <string>
+```
+
+#### `<alert_test_case>`
+
+vmalert by default adds `alertgroup` and `alertname` to the generated alerts and time series. 
+So you will need to specify both `groupname` and `alertname` under a single `<alert_test_case>`, 
+but no need to add them under `exp_alerts`.
+You can also pass `--disableAlertgroupLabel` to prevent vmalert from adding `alertgroup` label.
+
+```
+# The time elapsed from time=0s when this alerting rule should be checked.
+# Means this rule should be firing at this point, or shouldn't be firing if 'exp_alerts' is empty.
+eval_time: <duration>
+
+# Name of the group name to be tested.
+groupname: <string>
+
+# Name of the alert to be tested.
+alertname: <string>
+
+# List of the expected alerts that are firing under the given alertname at
+# the given evaluation time. If you want to test if an alerting rule should
+# not be firing, then you can mention only the fields above and leave 'exp_alerts' empty.
+exp_alerts:
+  [ - <alert> ]
+```
+
+#### `<alert>`
+
+```
+# These are the expanded labels and annotations of the expected alert.
+# Note: labels also include the labels of the sample associated with the alert
+exp_labels:
+  [ <labelname>: <string> ]
+exp_annotations:
+  [ <labelname>: <string> ]
+```
+
+#### `<metricsql_expr_test>`
+
+```
+# Expression to evaluate
+expr: <string>
+
+# The time elapsed from time=0s when this expression be evaluated.
+eval_time: <duration>
+
+# Expected samples at the given evaluation time.
+exp_samples:
+  [ - <sample> ]
+```
+
+#### `<sample>`
+
+```
+# Labels of the sample in usual series notation '<metric name>{<label name>=<label value>, ...}'
+# Examples:
+#      series_name{label1="value1", label2="value2"}
+#      go_goroutines{job="prometheus", instance="localhost:9090"}
+labels: <string>
+
+# The expected value of the Metricsql expression.
+value: <number>
+```
+
+### Example
+
+This is an example input file for unit testing which will pass.
+`test.yaml` is the test file which follows the syntax above and `alerts.yaml` contains the alerting rules.
+
+With `rules.yaml` in the same directory, run `./vmalert -unittestFile=./unittest/testdata/test.yaml`.
+
+#### `test.yaml`
+
+```
+rule_files:
+  - rules.yaml
+
+evaluation_interval: 1m
+
+tests:
+  - interval: 1m
+    input_series:
+      - series: 'up{job="prometheus", instance="localhost:9090"}'
+        values: "0+0x1440"
+
+    metricsql_expr_test:
+      - expr: suquery_interval_test
+        eval_time: 4m
+        exp_samples:
+          - labels: '{__name__="suquery_interval_test", datacenter="dc-123", instance="localhost:9090", job="prometheus"}'
+            value: 1
+
+    alert_rule_test:
+      - eval_time: 2h
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts:
+          - exp_labels:
+              job: prometheus
+              severity: page
+              instance: localhost:9090
+              datacenter: dc-123
+            exp_annotations:
+              summary: "Instance localhost:9090 down"
+              description: "localhost:9090 of job prometheus has been down for more than 5 minutes."
+
+      - eval_time: 0
+        groupname: group1
+        alertname: AlwaysFiring
+        exp_alerts:
+          - exp_labels:
+              datacenter: dc-123
+
+      - eval_time: 0
+        groupname: group1
+        alertname: InstanceDown
+        exp_alerts: []
+
+    external_labels:
+      datacenter: dc-123
+```
+
+#### `alerts.yaml`
+
+```
+# This is the rules file.
+
+groups:
+  - name: group1
+    rules:
+      - alert: InstanceDown
+        expr: up == 0
+        for: 5m
+        labels:
+          severity: page
+        annotations:
+          summary: "Instance {{ $labels.instance }} down"
+          description: "{{ $labels.instance }} of job {{ $labels.job }} has been down for more than 5 minutes."
+      - alert: AlwaysFiring
+        expr: 1
+
+  - name: group2
+    rules:
+      - record: job:test:count_over_time1m
+        expr: sum without(instance) (count_over_time(test[1m]))
+      - record: suquery_interval_test
+        expr: count_over_time(up[5m:])
+```
 
 ## Monitoring
 
@@ -705,31 +999,42 @@ a review to the dashboard.
 
 ## Troubleshooting
 
-vmalert executes configured rules within certain intervals. It is expected that at the moment when rule is executed,
-the data is already present in configured `-datasource.url`:
+### Data delay
+
+Data delay is one of the most common issues with rules execution.
+vmalert executes configured rules within certain intervals at specifics timestamps. 
+It expects that the data is already present in configured `-datasource.url` at the moment of time when rule is executed:
 
 <img alt="vmalert expected evaluation" src="vmalert_ts_normal.gif">
 
 Usually, troubles start to appear when data in `-datasource.url` is delayed or absent. In such cases, evaluations
-may get empty response from datasource and produce empty recording rules or reset alerts state:
+may get empty response from the datasource and produce empty recording rules or reset alerts state:
 
 <img alt="vmalert evaluation when data is delayed" src="vmalert_ts_data_delay.gif">
 
-By default, recently written samples to VictoriaMetrics aren't visible for queries for up to 30s.
-This behavior is controlled by `-search.latencyOffset` command-line flag and the `latency_offset` query ag at `vmselect`.
-Usually, this results into a 30s shift for recording rules results.
-Note that too small value passed to `-search.latencyOffset` or to `latency_offest` query arg may lead to incomplete query results.
+Try the following recommendations to reduce the chance of hitting the data delay issue:
 
-Try the following recommendations in such cases:
+* Always configure group's `evaluationInterval` to be bigger or at least equal to 
+[time series resolution](https://docs.victoriametrics.com/keyConcepts.html#time-series-resolution);
+* Ensure that `[duration]` value is at least twice bigger than 
+[time series resolution](https://docs.victoriametrics.com/keyConcepts.html#time-series-resolution). For example,
+if expression is `rate(my_metric[2m]) > 0` then ensure that `my_metric` resolution is at least `1m` or better `30s`. 
+If you use VictoriaMetrics as datasource, `[duration]` can be omitted and VictoriaMetrics will adjust it automatically.
+* If you know in advance, that data in datasource is delayed - try changing vmalerts `-datasource.lookback`
+command-line flag to add a time shift for evaluations. Or extend `[duration]` to tolerate the delay.
+For example, `max_over_time(errors_total[10m]) > 0` will be active even if there is no data in datasource for last `9m`.
+* If [time series resolution](https://docs.victoriametrics.com/keyConcepts.html#time-series-resolution)
+in datasource is inconsistent or `>=5min` - try changing vmalerts `-datasource.queryStep` command-line flag to specify
+how far search query can lookback for the recent datapoint. The recommendation is to have the step 
+at least two times bigger than the resolution.
 
-* Always configure group's `evaluationInterval` to be bigger or equal to `scrape_interval` at which metrics
-are delivered to the datasource;
-* If you know in advance, that data in datasource is delayed - try changing vmalert's `-datasource.lookback`
-command-line flag to add a time shift for evaluations;
-* If time intervals between datapoints in datasource are irregular or `>=5min` - try changing vmalert's
-`-datasource.queryStep` command-line flag to specify how far search query can lookback for the recent datapoint. 
-The recommendation is to have the step at least two times bigger than `scrape_interval`, since
-there are no guarantees that scrape will not fail.
+> Please note, data delay is inevitable in distributed systems. And it is better to account for it instead of ignoring.
+
+By default, recently written samples to VictoriaMetrics aren't visible for queries for up to 30s
+(see `-search.latencyOffset` command-line flag at vmselect). Such delay is needed to eliminate risk of incomplete
+data on the moment of querying, since metrics collectors won't be able to deliver the data in time.
+
+### Alerts state
 
 Sometimes, it is not clear why some specific alert fired or didn't fire. It is very important to remember, that
 alerts with `for: 0` fire immediately when their expression becomes true. And alerts with `for > 0` will fire only
@@ -742,7 +1047,8 @@ If `-remoteWrite.url` command-line flag is configured, vmalert will persist aler
 changed in time.
 
 vmalert stores last `-rule.updateEntriesLimit` (or `update_entries_limit` [per-rule config](https://docs.victoriametrics.com/vmalert.html#alerting-rules)) 
-state updates for each rule. To check updates, click on `Details` link next to rule's name on `/vmalert/groups` page 
+state updates for each rule starting from [v1.86](https://docs.victoriametrics.com/CHANGELOG.html#v1860).
+To check updates, click on `Details` link next to rule's name on `/vmalert/groups` page 
 and check the `Last updates` section:
 
 <img alt="vmalert state" src="vmalert_state.png">
@@ -752,8 +1058,10 @@ HTTP request sent by vmalert to the `-datasource.url` during evaluation. If spec
 no samples returned and curl command returns data - then it is very likely there was no data in datasource on the
 moment when rule was evaluated.
 
-vmalert allows configuring more detailed logging for specific alerting rule. Just set `debug: true` in rule's configuration
-and vmalert will start printing additional log messages:
+### Debug mode
+
+vmalert allows configuring more detailed logging for specific alerting rule starting from [v1.82](https://docs.victoriametrics.com/CHANGELOG.html#v1820).
+Just set `debug: true` in rule's configuration and vmalert will start printing additional log messages:
 ```terminal
 2022-09-15T13:35:41.155Z  DEBUG rule "TestGroup":"Conns" (2601299393013563564) at 2022-09-15T15:35:41+02:00: query returned 0 samples (elapsed: 5.896041ms)
 2022-09-15T13:35:56.149Z  DEBUG datasource request: executing POST request with params "denyPartialResponse=true&query=sum%28vm_tcplistener_conns%7Binstance%3D%22localhost%3A8429%22%7D%29+by%28instance%29+%3E+0&step=15s&time=1663248945"
@@ -764,6 +1072,49 @@ and vmalert will start printing additional log messages:
 2022-09-15T13:36:56.153Z  DEBUG rule "TestGroup":"Conns" (2601299393013563564) at 2022-09-15T15:36:56+02:00: alert 10705778000901301787 {alertgroup="TestGroup",alertname="Conns",cluster="east-1",instance="localhost:8429",replica="a"} PENDING => FIRING: 1m0s since becoming active at 2022-09-15 15:35:56.126006 +0200 CEST m=+39.384575417
 ```
 
+### Never-firing alerts
+
+vmalert can detect if alert's expression doesn't match any time series in runtime 
+starting from [v1.91](https://docs.victoriametrics.com/CHANGELOG.html#v1910). This problem usually happens
+when alerting expression selects time series which aren't present in the datasource (i.e. wrong `job` label)
+or there is a typo in the series selector (i.e. `env=rpod`). Such alerting rules will be marked with special icon in 
+vmalerts UI and exposed via `vmalert_alerting_rules_last_evaluation_series_fetched` metric. The metric value will
+show how many time series were matched before the filtering by rule's expression. If metric value is `-1`, then
+this feature is not supported by the datasource (old versions of VictoriaMetrics). The following expression can be
+used to detect rules matching no series:
+```
+max(vmalert_alerting_rules_last_evaluation_series_fetched) by(group, alertname) == 0
+```
+
+See more details [here](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4039).
+This feature is available only if vmalert is using VictoriaMetrics v1.90 or higher as a datasource.
+
+### Series with the same labelset
+
+vmalert can produce the following error message during rules evaluation:
+```
+result contains metrics with the same labelset after applying rule labels
+```
+
+The error means there is a collision between [time series](https://docs.victoriametrics.com/keyConcepts.html#time-series)
+after applying extra labels to result.
+
+For example, a rule with `expr: foo > 0` returns two distinct time series in response:
+```
+foo{bar="baz"} 1
+foo{bar="qux"} 2
+```
+
+If user configures `-external.label=bar=baz` cmd-line flag to enforce
+adding `bar="baz"` label-value pair, then time series won't be distinct anymore:
+```
+foo{bar="baz"} 1
+foo{bar="baz"} 2 # 'bar' label was overriden by `-external.label=bar=baz
+```
+
+The same issue can be caused by collision of configured `labels` on [Group](#groups) or [Rule](#rules) levels.
+To fix it one should avoid collisions by carefully picking label overrides in configuration.
+
 
 ## Profiling
 
@@ -803,11 +1154,11 @@ command-line flags with their descriptions.
 
 The shortlist of configuration flags is the following:
 {% raw  %}
-```
+```console
   -clusterMode
      If clusterMode is enabled, then vmalert automatically adds the tenant specified in config groups to -datasource.url, -remoteWrite.url and -remoteRead.url. See https://docs.victoriametrics.com/vmalert.html#multitenancy . This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
   -configCheckInterval duration
-     Interval for checking for changes in '-rule' or '-notifier.config' files. By default the checking is disabled. Send SIGHUP signal in order to force config check for changes.
+     Interval for checking for changes in '-rule' or '-notifier.config' files. By default, the checking is disabled. Send SIGHUP signal in order to force config check for changes.
   -datasource.appendTypePrefix
      Whether to add type prefix to -datasource.url based on the query type. Set to true if sending different query types to the vmselect URL.
   -datasource.basicAuth.password string
@@ -822,6 +1173,8 @@ The shortlist of configuration flags is the following:
      Optional path to bearer token file to use for -datasource.url.
   -datasource.disableKeepAlive
      Whether to disable long-lived connections to the datasource. If true, disables HTTP keep-alives and will only use the connection to the server for a single HTTP request.
+  -datasource.disableStepParam
+     Whether to disable adding 'step' param to the issued instant queries. This might be useful when using vmalert with datasources that do not support 'step' param for instant queries, like Google Managed Prometheus. It is not recommended to enable this flag if you use vmalert with VictoriaMetrics.
   -datasource.headers string
      Optional HTTP extraHeaders to send with each request to the corresponding -datasource.url. For example, -datasource.headers='My-Auth:foobar' would send 'My-Auth: foobar' HTTP header with every request to the corresponding -datasource.url. Multiple headers must be delimited by '^^': -datasource.headers='header1:value1^^header2:value2'
   -datasource.lookback duration
@@ -841,7 +1194,7 @@ The shortlist of configuration flags is the following:
   -datasource.queryStep duration
      How far a value can fallback to when evaluating queries. For example, if -datasource.queryStep=15s then param "step" with value "15s" will be added to every query. If set to 0, rule's evaluation interval will be used instead. (default 5m0s)
   -datasource.queryTimeAlignment
-     Whether to align "time" parameter with evaluation interval.Alignment supposed to produce deterministic results despite of number of vmalert replicas or time they were started. See more details here https://github.com/VictoriaMetrics/VictoriaMetrics/pull/1257 (default true)
+     Whether to align "time" parameter with evaluation interval.Alignment supposed to produce deterministic results despite number of vmalert replicas or time they were started. See more details here https://github.com/VictoriaMetrics/VictoriaMetrics/pull/1257 (default true)
   -datasource.roundDigits int
      Adds "round_digits" GET param to datasource requests. In VM "round_digits" limits the number of digits after the decimal point in response values.
   -datasource.showURL
@@ -867,9 +1220,9 @@ The shortlist of configuration flags is the following:
   -dryRun
      Whether to check only config files without running vmalert. The rules file are validated. The -rule flag must be specified.
   -enableTCP6
-     Whether to enable IPv6 for listening and dialing. By default only IPv4 TCP and UDP is used
+     Whether to enable IPv6 for listening and dialing. By default, only IPv4 TCP and UDP are used
   -envflag.enable
-     Whether to enable reading flags from environment variables additionally to command line. Command line flag values have priority over values from environment vars. Flags are read only from command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
+     Whether to enable reading flags from environment variables in addition to the command line. Command line flag values have priority over values from environment vars. Flags are read only from the command line if this flag isn't set. See https://docs.victoriametrics.com/#environment-variables for more details
   -envflag.prefix string
      Prefix for environment variables if -envflag.enable is set
   -eula
@@ -877,20 +1230,20 @@ The shortlist of configuration flags is the following:
   -evaluationInterval duration
      How often to evaluate the rules (default 1m0s)
   -external.alert.source string
-     External Alert Source allows to override the Source link for alerts sent to AlertManager for cases where you want to build a custom link to Grafana, Prometheus or any other service. Supports templating - see https://docs.victoriametrics.com/vmalert.html#templating . For example, link to Grafana: -external.alert.source='explore?orgId=1&left=["now-1h","now","VictoriaMetrics",{"expr":{{$expr|jsonEscape|queryEscape}} },{"mode":"Metrics"},{"ui":[true,true,true,"none"]}]' . If empty 'vmalert/alert?group_id={{.GroupID}}&alert_id={{.AlertID}}' is used.
+     External Alert Source allows to override the Source link for alerts sent to AlertManager for cases where you want to build a custom link to Grafana, Prometheus or any other service. Supports templating - see https://docs.victoriametrics.com/vmalert.html#templating . For example, link to Grafana: -external.alert.source='explore?orgId=1&left={"datasource":"VictoriaMetrics","queries":[{"expr":{{$expr|jsonEscape|queryEscape}},"refId":"A"}],"range":{"from":"now-1h","to":"now"}}'. Link to VMUI: -external.alert.source='vmui/#/?g0.expr={{.Expr|queryEscape}}'. If empty 'vmalert/alert?group_id={{.GroupID}}&alert_id={{.AlertID}}' is used.
   -external.label array
      Optional label in the form 'Name=value' to add to all generated recording rules and alerts. Pass multiple -label flags in order to add multiple label sets.
      Supports an array of values separated by comma or specified via multiple flags.
   -external.url string
-     External URL is used as alert's source for sent alerts to the notifier
+     External URL is used as alert's source for sent alerts to the notifier. By default, hostname is used as address.
   -flagsAuthKey string
      Auth key for /flags endpoint. It must be passed via authKey query arg. It overrides httpAuth.* settings
   -fs.disableMmap
-     Whether to use pread() instead of mmap() for reading data files. By default mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
+     Whether to use pread() instead of mmap() for reading data files. By default, mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
   -http.connTimeout duration
      Incoming http connections are closed after the configured timeout. This may help to spread the incoming load among a cluster of services behind a load balancer. Please note that the real timeout may be bigger by up to 10% as a protection against the thundering herd problem (default 2m0s)
   -http.disableResponseCompression
-     Disable compression of HTTP responses to save CPU resources. By default compression is enabled to save network bandwidth
+     Disable compression of HTTP responses to save CPU resources. By default, compression is enabled to save network bandwidth
   -http.idleConnTimeout duration
      Timeout for incoming idle http connections (default 1m0s)
   -http.maxGracefulShutdownDuration duration
@@ -900,13 +1253,19 @@ The shortlist of configuration flags is the following:
   -http.shutdownDelay duration
      Optional delay before http server shutdown. During this delay, the server returns non-OK responses from /health page, so load balancers can route new requests to other servers
   -httpAuth.password string
-     Password for HTTP Basic Auth. The authentication is disabled if -httpAuth.username is empty
+     Password for HTTP server's Basic Auth. The authentication is disabled if -httpAuth.username is empty
   -httpAuth.username string
-     Username for HTTP Basic Auth. The authentication is disabled if empty. See also -httpAuth.password
+     Username for HTTP server's Basic Auth. The authentication is disabled if empty. See also -httpAuth.password
   -httpListenAddr string
      Address to listen for http connections. See also -httpListenAddr.useProxyProtocol (default ":8880")
   -httpListenAddr.useProxyProtocol
-     Whether to use proxy protocol for connections accepted at -httpListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt
+     Whether to use proxy protocol for connections accepted at -httpListenAddr . See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt . With enabled proxy protocol http server cannot serve regular /metrics endpoint. Use -pushmetrics.url for metrics pushing
+  -internStringCacheExpireDuration duration
+     The expiry duration for caches for interned strings. See https://en.wikipedia.org/wiki/String_interning . See also -internStringMaxLen and -internStringDisableCache (default 6m0s)
+  -internStringDisableCache
+     Whether to disable caches for interned strings. This may reduce memory usage at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning . See also -internStringCacheExpireDuration and -internStringMaxLen
+  -internStringMaxLen int
+     The maximum length for strings to intern. A lower limit may save memory at the cost of higher CPU usage. See https://en.wikipedia.org/wiki/String_interning . See also -internStringDisableCache and -internStringCacheExpireDuration (default 500)
   -loggerDisableTimestamps
      Whether to disable writing timestamps in logs
   -loggerErrorsPerSecondLimit int
@@ -923,6 +1282,11 @@ The shortlist of configuration flags is the following:
      Timezone to use for timestamps in logs. Timezone must be a valid IANA Time Zone. For example: America/New_York, Europe/Berlin, Etc/GMT+3 or Local (default "UTC")
   -loggerWarnsPerSecondLimit int
      Per-second limit on the number of WARN messages. If more than the given number of warns are emitted per second, then the remaining warns are suppressed. Zero values disable the rate limit
+  -memory.allowedBytes size
+     Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to a non-zero value. Too low a value may increase the cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from the OS page cache resulting in higher disk IO usage
+     Supports the following optional suffixes for size values: KB, MB, GB, TB, KiB, MiB, GiB, TiB (default 0)
+  -memory.allowedPercent float
+     Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low a value may increase cache miss rate usually resulting in higher CPU and disk IO usage. Too high a value may evict too much data from the OS page cache which will result in higher disk IO usage (default 60)
   -metricsAuthKey string
      Auth key for /metrics endpoint. It must be passed via authKey query arg. It overrides httpAuth.* settings
   -notifier.basicAuth.password array
@@ -960,7 +1324,7 @@ The shortlist of configuration flags is the following:
   -notifier.suppressDuplicateTargetErrors
      Whether to suppress 'duplicate target' errors during discovery
   -notifier.tlsCAFile array
-     Optional path to TLS CA file to use for verifying connections to -notifier.url. By default system CA is used
+     Optional path to TLS CA file to use for verifying connections to -notifier.url. By default, system CA is used
      Supports an array of values separated by comma or specified via multiple flags.
   -notifier.tlsCertFile array
      Optional path to client-side TLS certificate file to use when connecting to -notifier.url
@@ -972,11 +1336,13 @@ The shortlist of configuration flags is the following:
      Optional path to client-side TLS certificate key to use when connecting to -notifier.url
      Supports an array of values separated by comma or specified via multiple flags.
   -notifier.tlsServerName array
-     Optional TLS server name to use for connections to -notifier.url. By default the server name from -notifier.url is used
+     Optional TLS server name to use for connections to -notifier.url. By default, the server name from -notifier.url is used
      Supports an array of values separated by comma or specified via multiple flags.
   -notifier.url array
      Prometheus Alertmanager URL, e.g. http://127.0.0.1:9093. List all Alertmanager URLs if it runs in the cluster mode to ensure high availability.
      Supports an array of values separated by comma or specified via multiple flags.
+  -notifier.blackhole bool
+     Whether to blackhole alerting notifications. Enable this flag if you want vmalert to evaluate alerting rules without sending any notifications to external receivers (eg. alertmanager). `-notifier.url`, `-notifier.config` and `-notifier.blackhole` are mutually exclusive.
   -pprofAuthKey string
      Auth key for /debug/pprof/* endpoints. It must be passed via authKey query arg. It overrides httpAuth.* settings
   -promscrape.consul.waitTime duration
@@ -995,7 +1361,7 @@ The shortlist of configuration flags is the following:
   -pushmetrics.interval duration
      Interval for pushing metrics to -pushmetrics.url (default 10s)
   -pushmetrics.url array
-     Optional URL to push metrics exposed at /metrics page. See https://docs.victoriametrics.com/#push-metrics . By default metrics exposed at /metrics page aren't pushed to any remote storage
+     Optional URL to push metrics exposed at /metrics page. See https://docs.victoriametrics.com/#push-metrics . By default, metrics exposed at /metrics page aren't pushed to any remote storage
      Supports an array of values separated by comma or specified via multiple flags.
   -remoteRead.basicAuth.password string
      Optional basic auth password for -remoteRead.url
@@ -1028,7 +1394,7 @@ The shortlist of configuration flags is the following:
   -remoteRead.showURL
      Whether to show -remoteRead.url in the exported metrics. It is hidden by default, since it can contain sensitive info such as auth key
   -remoteRead.tlsCAFile string
-     Optional path to TLS CA file to use for verifying connections to -remoteRead.url. By default system CA is used
+     Optional path to TLS CA file to use for verifying connections to -remoteRead.url. By default, system CA is used
   -remoteRead.tlsCertFile string
      Optional path to client-side TLS certificate file to use when connecting to -remoteRead.url
   -remoteRead.tlsInsecureSkipVerify
@@ -1036,7 +1402,7 @@ The shortlist of configuration flags is the following:
   -remoteRead.tlsKeyFile string
      Optional path to client-side TLS certificate key to use when connecting to -remoteRead.url
   -remoteRead.tlsServerName string
-     Optional TLS server name to use for connections to -remoteRead.url. By default the server name from -remoteRead.url is used
+     Optional TLS server name to use for connections to -remoteRead.url. By default, the server name from -remoteRead.url is used
   -remoteRead.url vmalert
      Optional URL to datasource compatible with Prometheus HTTP API. It can be single node VictoriaMetrics or vmselect.Remote read is used to restore alerts state.This configuration makes sense only if vmalert was configured with `remoteWrite.url` before and has been successfully persisted its state. E.g. http://127.0.0.1:8428. See also '-remoteRead.disablePathAppend', '-remoteRead.showURL'.
   -remoteWrite.basicAuth.password string
@@ -1058,7 +1424,7 @@ The shortlist of configuration flags is the following:
   -remoteWrite.headers string
      Optional HTTP headers to send with each request to the corresponding -remoteWrite.url. For example, -remoteWrite.headers='My-Auth:foobar' would send 'My-Auth: foobar' HTTP header with every request to the corresponding -remoteWrite.url. Multiple headers must be delimited by '^^': -remoteWrite.headers='header1:value1^^header2:value2'
   -remoteWrite.maxBatchSize int
-     Defines defines max number of timeseries to be flushed at once (default 1000)
+     Defines max number of timeseries to be flushed at once (default 1000)
   -remoteWrite.maxQueueSize int
      Defines the max number of pending datapoints to remote write endpoint (default 100000)
   -remoteWrite.oauth2.clientID string
@@ -1071,12 +1437,16 @@ The shortlist of configuration flags is the following:
      Optional OAuth2 scopes to use for -notifier.url. Scopes must be delimited by ';'.
   -remoteWrite.oauth2.tokenUrl string
      Optional OAuth2 tokenURL to use for -notifier.url.
+  -remoteWrite.retryMaxTime duration
+     The max time spent on retry attempts for the failed remote-write request. Change this value if it is expected for remoteWrite.url to be unreachable for more than -remoteWrite.retryMaxTime. See also -remoteWrite.retryMinInterval (default 30s)
+  -remoteWrite.retryMinInterval duration
+     The minimum delay between retry attempts. Every next retry attempt will double the delay to prevent hammering of remote database. See also -remoteWrite.retryMaxInterval (default 1s)
   -remoteWrite.sendTimeout duration
      Timeout for sending data to the configured -remoteWrite.url. (default 30s)
   -remoteWrite.showURL
      Whether to show -remoteWrite.url in the exported metrics. It is hidden by default, since it can contain sensitive info such as auth key
   -remoteWrite.tlsCAFile string
-     Optional path to TLS CA file to use for verifying connections to -remoteWrite.url. By default system CA is used
+     Optional path to TLS CA file to use for verifying connections to -remoteWrite.url. By default, system CA is used
   -remoteWrite.tlsCertFile string
      Optional path to client-side TLS certificate file to use when connecting to -remoteWrite.url
   -remoteWrite.tlsInsecureSkipVerify
@@ -1084,50 +1454,76 @@ The shortlist of configuration flags is the following:
   -remoteWrite.tlsKeyFile string
      Optional path to client-side TLS certificate key to use when connecting to -remoteWrite.url
   -remoteWrite.tlsServerName string
-     Optional TLS server name to use for connections to -remoteWrite.url. By default the server name from -remoteWrite.url is used
+     Optional TLS server name to use for connections to -remoteWrite.url. By default, the server name from -remoteWrite.url is used
   -remoteWrite.url string
      Optional URL to VictoriaMetrics or vminsert where to persist alerts state and recording rules results in form of timeseries. For example, if -remoteWrite.url=http://127.0.0.1:8428 is specified, then the alerts state will be written to http://127.0.0.1:8428/api/v1/write . See also -remoteWrite.disablePathAppend, '-remoteWrite.showURL'.
   -replay.disableProgressBar
      Whether to disable rendering progress bars during the replay. Progress bar rendering might be verbose or break the logs parsing, so it is recommended to be disabled when not used in interactive mode.
-  -replay.maxDatapointsPerQuery int
-     Max number of data points expected in one request. It affects the max time range for every `/query_range` request during the replay. The higher the value, the less requests will be made during replay. (default 1000)
+  -replay.maxDatapointsPerQuery /query_range
+     Max number of data points expected in one request. It affects the max time range for every /query_range request during the replay. The higher the value, the less requests will be made during replay. (default 1000)
   -replay.ruleRetryAttempts int
      Defines how many retries to make before giving up on rule if request for it returns an error. (default 5)
   -replay.rulesDelay duration
-     Delay between rules evaluation within the group. Could be important if there are chained rules inside of the groupand processing need to wait for previous rule results to be persisted by remote storage before evaluating the next rule.Keep it equal or bigger than -remoteWrite.flushInterval. (default 1s)
+     Delay between rules evaluation within the group. Could be important if there are chained rules inside the group and processing need to wait for previous rule results to be persisted by remote storage before evaluating the next rule.Keep it equal or bigger than -remoteWrite.flushInterval. (default 1s)
   -replay.timeFrom string
      The time filter in RFC3339 format to select time series with timestamp equal or higher than provided value. E.g. '2020-01-01T20:07:00Z'
   -replay.timeTo string
      The time filter in RFC3339 format to select timeseries with timestamp equal or lower than provided value. E.g. '2020-01-01T20:07:00Z'
   -rule array
-     Path to the file with alert rules.
-     Supports patterns. Flag can be specified multiple times.
+     Path to the files or http url with alerting and/or recording rules.
+     Supports hierarchical patterns and regexpes.
      Examples:
-      -rule="/path/to/file". Path to a single file with alerting rules
-      -rule="dir/*.yaml" -rule="/*.yaml". Relative path to all .yaml files in "dir" folder,
-     absolute path to all .yaml files in root.
+      -rule="/path/to/file". Path to a single file with alerting rules.
+      -rule="http://<some-server-addr>/path/to/rules". HTTP URL to a page with alerting rules.
+      -rule="dir/*.yaml" -rule="/*.yaml" -rule="gcs://vmalert-rules/tenant_%{TENANT_ID}/prod". 
+      -rule="dir/**/*.yaml". Includes all the .yaml files in "dir" subfolders recursively.
      Rule files may contain %{ENV_VAR} placeholders, which are substituted by the corresponding env vars.
+     
+     Enterprise version of vmalert supports S3 and GCS paths to rules.
+     For example: gs://bucket/path/to/rules, s3://bucket/path/to/rules
+     S3 and GCS paths support only matching by prefix, e.g. s3://bucket/dir/rule_ matches
+     all files with prefix rule_ in folder dir.
+     See https://docs.victoriametrics.com/vmalert.html#reading-rules-from-object-storage
+     
      Supports an array of values separated by comma or specified via multiple flags.
   -rule.configCheckInterval duration
-     Interval for checking for changes in '-rule' files. By default the checking is disabled. Send SIGHUP signal in order to force config check for changes. DEPRECATED - see '-configCheckInterval' instead
+     Interval for checking for changes in '-rule' files. By default, the checking is disabled. Send SIGHUP signal in order to force config check for changes. DEPRECATED - see '-configCheckInterval' instead
   -rule.maxResolveDuration duration
-     Limits the maximum duration for automatic alert expiration, which is by default equal to 3 evaluation intervals of the parent group.
+     Limits the maximum duration for automatic alert expiration, which by default is 4 times evaluationInterval of the parent group.
   -rule.resendDelay duration
      Minimum amount of time to wait before resending an alert to notifier
   -rule.templates array
      Path or glob pattern to location with go template definitions
-      for rules annotations templating. Flag can be specified multiple times.
+     	for rules annotations templating. Flag can be specified multiple times.
      Examples:
       -rule.templates="/path/to/file". Path to a single file with go templates
       -rule.templates="dir/*.tpl" -rule.templates="/*.tpl". Relative path to all .tpl files in "dir" folder,
      absolute path to all .tpl files in root.
+      -rule.templates="dir/**/*.tpl". Includes all the .tpl files in "dir" subfolders recursively.
+     
      Supports an array of values separated by comma or specified via multiple flags.
   -rule.updateEntriesLimit int
-     Defines the max number of rule's state updates stored in-memory. Rule's updates are available on rule's Details page and are used for debugging purposes. The number of stored updates can be overriden per rule via update_entries_limit param. (default 20)
+     Defines the max number of rule's state updates stored in-memory. Rule's updates are available on rule's Details page and are used for debugging purposes. The number of stored updates can be overridden per rule via update_entries_limit param. (default 20)
   -rule.validateExpressions
      Whether to validate rules expressions via MetricsQL engine (default true)
   -rule.validateTemplates
      Whether to validate annotation and label templates (default true)
+  -s2a_enable_appengine_dialer
+     If true, opportunistically use AppEngine-specific dialer to call S2A.
+  -s2a_timeout duration
+     Timeout enforced on the connection to the S2A service for handshake. (default 3s)
+  -s3.configFilePath string
+     Path to file with S3 configs. Configs are loaded from default location if not set.
+     See https://docs.aws.amazon.com/general/latest/gr/aws-security-credentials.html . This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
+  -s3.configProfile string
+     Profile name for S3 configs. If no set, the value of the environment variable will be loaded (AWS_PROFILE or AWS_DEFAULT_PROFILE), or if both not set, DefaultSharedConfigProfile is used. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
+  -s3.credsFilePath string
+     Path to file with GCS or S3 credentials. Credentials are loaded from default locations if not set.
+     See https://cloud.google.com/iam/docs/creating-managing-service-account-keys and https://docs.aws.amazon.com/general/latest/gr/aws-security-credentials.html . This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
+  -s3.customEndpoint string
+     Custom S3 endpoint for use with S3-compatible storages (e.g. MinIO). S3 is used if not set. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html
+  -s3.forcePathStyle
+     Prefixing endpoint with bucket name when set false, true by default. This flag is available only in VictoriaMetrics enterprise. See https://docs.victoriametrics.com/enterprise.html (default true)
   -tls
      Whether to enable TLS for incoming HTTP requests at -httpListenAddr (aka https). -tlsCertFile and -tlsKeyFile must be set if -tls is set
   -tlsCertFile string
@@ -1139,6 +1535,11 @@ The shortlist of configuration flags is the following:
      Path to file with TLS key if -tls is set. The provided key file is automatically re-read every second, so it can be dynamically updated
   -tlsMinVersion string
      Optional minimum TLS version to use for incoming requests over HTTPS if -tls is set. Supported values: TLS10, TLS11, TLS12, TLS13
+  -unittestFile array
+     Path to the unit test files. When set, vmalert starts in unit test mode and performs only tests on configured files.
+     Examples:
+      -unittestFile="./unittest/testdata/test1.yaml,./unittest/testdata/test2.yaml".
+     See more information here https://docs.victoriametrics.com/vmalert.html#unit-testing-for-rules.
   -version
      Show VictoriaMetrics version
 ```
@@ -1188,7 +1589,7 @@ The configuration file allows to configure static notifiers, discover notifiers
 and [DNS](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dns_sd_config):
 For example:
 
-```
+```yaml
 static_configs:
   - targets:
       - localhost:9093
@@ -1213,7 +1614,7 @@ to ensure [high availability](https://github.com/prometheus/alertmanager#high-av
 The configuration file [specification](https://github.com/VictoriaMetrics/VictoriaMetrics/blob/master/app/vmalert/notifier/config.go)
 is the following:
 
-```
+```yaml
 # Per-target Notifier timeout when pushing alerts.
 [ timeout: <duration> | default = 10s ]
 
@@ -1332,6 +1733,7 @@ docker push my-repo:my-version-name
 ```
 
 To run the built image in `victoria-metrics-k8s-stack` or `VMAlert` CR object apply the following config change:
+
 ```yaml
 kind: VMAlert
 spec:
@@ -1343,13 +1745,13 @@ spec:
 ### Development build
 
 1. [Install Go](https://golang.org/doc/install). The minimum supported version is Go 1.19.
-2. Run `make vmalert` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make vmalert` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `vmalert` binary and puts it into the `bin` folder.
 
 ### Production build
 
 1. [Install docker](https://docs.docker.com/install/).
-2. Run `make vmalert-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make vmalert-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `vmalert-prod` binary and puts it into the `bin` folder.
 
 ### ARM build
@@ -1359,11 +1761,11 @@ ARM build may run on Raspberry Pi or on [energy-efficient ARM servers](https://b
 ### Development ARM build
 
 1. [Install Go](https://golang.org/doc/install). The minimum supported version is Go 1.19.
-2. Run `make vmalert-linux-arm` or `make vmalert-linux-arm64` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make vmalert-linux-arm` or `make vmalert-linux-arm64` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `vmalert-linux-arm` or `vmalert-linux-arm64` binary respectively and puts it into the `bin` folder.
 
 ### Production ARM build
 
 1. [Install docker](https://docs.docker.com/install/).
-2. Run `make vmalert-linux-arm-prod` or `make vmalert-linux-arm64-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
+1. Run `make vmalert-linux-arm-prod` or `make vmalert-linux-arm64-prod` from the root folder of [the repository](https://github.com/VictoriaMetrics/VictoriaMetrics).
    It builds `vmalert-linux-arm-prod` or `vmalert-linux-arm64-prod` binary respectively and puts it into the `bin` folder.

app/vmalert/alerting.go

@@ -21,17 +21,18 @@ import (
 
 // AlertingRule is basic alert entity
 type AlertingRule struct {
-	Type         config.Type
-	RuleID       uint64
-	Name         string
-	Expr         string
-	For          time.Duration
-	Labels       map[string]string
-	Annotations  map[string]string
-	GroupID      uint64
-	GroupName    string
-	EvalInterval time.Duration
-	Debug        bool
+	Type          config.Type
+	RuleID        uint64
+	Name          string
+	Expr          string
+	For           time.Duration
+	KeepFiringFor time.Duration
+	Labels        map[string]string
+	Annotations   map[string]string
+	GroupID       uint64
+	GroupName     string
+	EvalInterval  time.Duration
+	Debug         bool
 
 	q datasource.Querier
 
@@ -47,25 +48,27 @@ type AlertingRule struct {
 }
 
 type alertingRuleMetrics struct {
-	errors  *utils.Gauge
-	pending *utils.Gauge
-	active  *utils.Gauge
-	samples *utils.Gauge
+	errors        *utils.Gauge
+	pending       *utils.Gauge
+	active        *utils.Gauge
+	samples       *utils.Gauge
+	seriesFetched *utils.Gauge
 }
 
 func newAlertingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rule) *AlertingRule {
 	ar := &AlertingRule{
-		Type:         group.Type,
-		RuleID:       cfg.ID,
-		Name:         cfg.Alert,
-		Expr:         cfg.Expr,
-		For:          cfg.For.Duration(),
-		Labels:       cfg.Labels,
-		Annotations:  cfg.Annotations,
-		GroupID:      group.ID(),
-		GroupName:    group.Name,
-		EvalInterval: group.Interval,
-		Debug:        cfg.Debug,
+		Type:          group.Type,
+		RuleID:        cfg.ID,
+		Name:          cfg.Alert,
+		Expr:          cfg.Expr,
+		For:           cfg.For.Duration(),
+		KeepFiringFor: cfg.KeepFiringFor.Duration(),
+		Labels:        cfg.Labels,
+		Annotations:   cfg.Annotations,
+		GroupID:       group.ID(),
+		GroupName:     group.Name,
+		EvalInterval:  group.Interval,
+		Debug:         cfg.Debug,
 		q: qb.BuildWithParams(datasource.QuerierParams{
 			DataSourceType:     group.Type.String(),
 			EvaluationInterval: group.Interval,
@@ -121,6 +124,21 @@ func newAlertingRule(qb datasource.QuerierBuilder, group *Group, cfg config.Rule
 			e := ar.state.getLast()
 			return float64(e.samples)
 		})
+	ar.metrics.seriesFetched = utils.GetOrCreateGauge(fmt.Sprintf(`vmalert_alerting_rules_last_evaluation_series_fetched{%s}`, labels),
+		func() float64 {
+			e := ar.state.getLast()
+			if e.seriesFetched == nil {
+				// means seriesFetched is unsupported
+				return -1
+			}
+			seriesFetched := float64(*e.seriesFetched)
+			if seriesFetched == 0 && e.samples > 0 {
+				// `alert: 0.95` will fetch no series
+				// but will get one time series in response.
+				seriesFetched = float64(e.samples)
+			}
+			return seriesFetched
+		})
 	return ar
 }
 
@@ -130,6 +148,7 @@ func (ar *AlertingRule) Close() {
 	ar.metrics.pending.Unregister()
 	ar.metrics.errors.Unregister()
 	ar.metrics.samples.Unregister()
+	ar.metrics.seriesFetched.Unregister()
 }
 
 // String implements Stringer interface
@@ -234,7 +253,7 @@ func (ar *AlertingRule) toLabels(m datasource.Metric, qFn templates.QueryFn) (*l
 // to get time series for backfilling.
 // It returns ALERT and ALERT_FOR_STATE time series as result.
 func (ar *AlertingRule) ExecRange(ctx context.Context, start, end time.Time) ([]prompbmarshal.TimeSeries, error) {
-	series, err := ar.q.QueryRange(ctx, ar.Expr, start, end)
+	res, err := ar.q.QueryRange(ctx, ar.Expr, start, end)
 	if err != nil {
 		return nil, err
 	}
@@ -242,7 +261,7 @@ func (ar *AlertingRule) ExecRange(ctx context.Context, start, end time.Time) ([]
 	qFn := func(query string) ([]datasource.Metric, error) {
 		return nil, fmt.Errorf("`query` template isn't supported in replay mode")
 	}
-	for _, s := range series {
+	for _, s := range res.Data {
 		a, err := ar.newAlert(s, nil, time.Time{}, qFn) // initial alert
 		if err != nil {
 			return nil, fmt.Errorf("failed to create alert: %s", err)
@@ -282,14 +301,15 @@ const resolvedRetention = 15 * time.Minute
 // Based on the Querier results AlertingRule maintains notifier.Alerts
 func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]prompbmarshal.TimeSeries, error) {
 	start := time.Now()
-	qMetrics, req, err := ar.q.Query(ctx, ar.Expr, ts)
+	res, req, err := ar.q.Query(ctx, ar.Expr, ts)
 	curState := ruleStateEntry{
-		time:     start,
-		at:       ts,
-		duration: time.Since(start),
-		samples:  len(qMetrics),
-		err:      err,
-		curl:     requestToCurl(req),
+		time:          start,
+		at:            ts,
+		duration:      time.Since(start),
+		samples:       len(res.Data),
+		seriesFetched: res.SeriesFetched,
+		err:           err,
+		curl:          requestToCurl(req),
 	}
 
 	defer func() {
@@ -315,11 +335,11 @@ func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]pr
 
 	qFn := func(query string) ([]datasource.Metric, error) {
 		res, _, err := ar.q.Query(ctx, query, ts)
-		return res, err
+		return res.Data, err
 	}
 	updated := make(map[uint64]struct{})
 	// update list of active alerts
-	for _, m := range qMetrics {
+	for _, m := range res.Data {
 		ls, err := ar.toLabels(m, qFn)
 		if err != nil {
 			curState.err = fmt.Errorf("failed to expand labels: %s", err)
@@ -348,6 +368,7 @@ func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]pr
 			if err != nil {
 				return nil, err
 			}
+			a.KeepFiringSince = time.Time{}
 			continue
 		}
 		a, err := ar.newAlert(m, ls, start, qFn)
@@ -373,12 +394,24 @@ func (ar *AlertingRule) Exec(ctx context.Context, ts time.Time, limit int) ([]pr
 				ar.logDebugf(ts, a, "PENDING => DELETED: is absent in current evaluation round")
 				continue
 			}
+			// check if alert should keep StateFiring if rule has
+			// `keep_firing_for` field
 			if a.State == notifier.StateFiring {
-				a.State = notifier.StateInactive
-				a.ResolvedAt = ts
-				ar.logDebugf(ts, a, "FIRING => INACTIVE: is absent in current evaluation round")
+				if ar.KeepFiringFor > 0 {
+					if a.KeepFiringSince.IsZero() {
+						a.KeepFiringSince = ts
+					}
+				}
+				// alerts with ar.KeepFiringFor>0 may remain FIRING
+				// even if their expression isn't true anymore
+				if ts.Sub(a.KeepFiringSince) > ar.KeepFiringFor {
+					a.State = notifier.StateInactive
+					a.ResolvedAt = ts
+					ar.logDebugf(ts, a, "FIRING => INACTIVE: is absent in current evaluation round")
+					continue
+				}
+				ar.logDebugf(ts, a, "KEEP_FIRING: will keep firing for %fs since %v", ar.KeepFiringFor.Seconds(), a.KeepFiringSince)
 			}
-			continue
 		}
 		numActivePending++
 		if a.State == notifier.StatePending && ts.Sub(a.ActiveAt) >= ar.For {
@@ -418,6 +451,7 @@ func (ar *AlertingRule) UpdateWith(r Rule) error {
 	}
 	ar.Expr = nr.Expr
 	ar.For = nr.For
+	ar.KeepFiringFor = nr.KeepFiringFor
 	ar.Labels = nr.Labels
 	ar.Annotations = nr.Annotations
 	ar.EvalInterval = nr.EvalInterval
@@ -485,22 +519,24 @@ func (ar *AlertingRule) AlertAPI(id uint64) *APIAlert {
 func (ar *AlertingRule) ToAPI() APIRule {
 	lastState := ar.state.getLast()
 	r := APIRule{
-		Type:           "alerting",
-		DatasourceType: ar.Type.String(),
-		Name:           ar.Name,
-		Query:          ar.Expr,
-		Duration:       ar.For.Seconds(),
-		Labels:         ar.Labels,
-		Annotations:    ar.Annotations,
-		LastEvaluation: lastState.time,
-		EvaluationTime: lastState.duration.Seconds(),
-		Health:         "ok",
-		State:          "inactive",
-		Alerts:         ar.AlertsToAPI(),
-		LastSamples:    lastState.samples,
-		MaxUpdates:     ar.state.size(),
-		Updates:        ar.state.getAll(),
-		Debug:          ar.Debug,
+		Type:              "alerting",
+		DatasourceType:    ar.Type.String(),
+		Name:              ar.Name,
+		Query:             ar.Expr,
+		Duration:          ar.For.Seconds(),
+		KeepFiringFor:     ar.KeepFiringFor.Seconds(),
+		Labels:            ar.Labels,
+		Annotations:       ar.Annotations,
+		LastEvaluation:    lastState.time,
+		EvaluationTime:    lastState.duration.Seconds(),
+		Health:            "ok",
+		State:             "inactive",
+		Alerts:            ar.AlertsToAPI(),
+		LastSamples:       lastState.samples,
+		LastSeriesFetched: lastState.seriesFetched,
+		MaxUpdates:        ar.state.size(),
+		Updates:           ar.state.getAll(),
+		Debug:             ar.Debug,
 
 		// encode as strings to avoid rounding in JSON
 		ID:      fmt.Sprintf("%d", ar.ID()),
@@ -557,6 +593,9 @@ func (ar *AlertingRule) newAlertAPI(a notifier.Alert) *APIAlert {
 	if alertURLGeneratorFn != nil {
 		aa.SourceLink = alertURLGeneratorFn(a)
 	}
+	if a.State == notifier.StateFiring && !a.KeepFiringSince.IsZero() {
+		aa.Stabilizing = true
+	}
 	return aa
 }
 
@@ -637,11 +676,12 @@ func (ar *AlertingRule) Restore(ctx context.Context, q datasource.Querier, ts ti
 
 		ar.logDebugf(ts, nil, "restoring alert state via query %q", expr)
 
-		qMetrics, _, err := q.Query(ctx, expr, ts)
+		res, _, err := q.Query(ctx, expr, ts)
 		if err != nil {
 			return err
 		}
 
+		qMetrics := res.Data
 		if len(qMetrics) < 1 {
 			ar.logDebugf(ts, nil, "no response was received from restore query")
 			continue

app/vmalert/alerting_test.go

@@ -113,7 +113,7 @@ func TestAlertingRule_Exec(t *testing.T) {
 	testCases := []struct {
 		rule      *AlertingRule
 		steps     [][]datasource.Metric
-		expAlerts []testAlert
+		expAlerts map[int][]testAlert
 	}{
 		{
 			newTestAlertingRule("empty", 0),
@@ -125,50 +125,8 @@ func TestAlertingRule_Exec(t *testing.T) {
 			[][]datasource.Metric{
 				{datasource.Metric{Values: []float64{1}, Timestamps: []int64{1}}},
 			},
-			[]testAlert{
-				{alert: &notifier.Alert{State: notifier.StateFiring}},
-			},
-		},
-		{
-			newTestAlertingRule("single-firing", 0),
-			[][]datasource.Metric{
-				{metricWithLabels(t, "name", "foo")},
-			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}},
-			},
-		},
-		{
-			newTestAlertingRule("single-firing=>inactive", 0),
-			[][]datasource.Metric{
-				{metricWithLabels(t, "name", "foo")},
-				{},
-			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}},
-			},
-		},
-		{
-			newTestAlertingRule("single-firing=>inactive=>firing", 0),
-			[][]datasource.Metric{
-				{metricWithLabels(t, "name", "foo")},
-				{},
-				{metricWithLabels(t, "name", "foo")},
-			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}},
-			},
-		},
-		{
-			newTestAlertingRule("single-firing=>inactive=>firing=>inactive", 0),
-			[][]datasource.Metric{
-				{metricWithLabels(t, "name", "foo")},
-				{},
-				{metricWithLabels(t, "name", "foo")},
-				{},
-			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}},
+			map[int][]testAlert{
+				0: {{alert: &notifier.Alert{State: notifier.StateFiring}}},
 			},
 		},
 		{
@@ -180,12 +138,16 @@ func TestAlertingRule_Exec(t *testing.T) {
 				{},
 				{},
 			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}},
+			map[int][]testAlert{
+				0: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				1: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}}},
+				2: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				3: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}}},
+				4: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}}},
 			},
 		},
 		{
-			newTestAlertingRule("single-firing=>inactive=>firing=>inactive=>empty=>firing", 0),
+			newTestAlertingRule("single-firing=>inactive=>firing=>inactive=>inactive=>firing", 0),
 			[][]datasource.Metric{
 				{metricWithLabels(t, "name", "foo")},
 				{},
@@ -194,8 +156,13 @@ func TestAlertingRule_Exec(t *testing.T) {
 				{},
 				{metricWithLabels(t, "name", "foo")},
 			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+			map[int][]testAlert{
+				0: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				1: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}}},
+				2: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				3: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}}},
+				4: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}}},
+				5: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
 			},
 		},
 		{
@@ -207,10 +174,12 @@ func TestAlertingRule_Exec(t *testing.T) {
 					metricWithLabels(t, "name", "foo2"),
 				},
 			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}},
-				{labels: []string{"name", "foo1"}, alert: &notifier.Alert{State: notifier.StateFiring}},
-				{labels: []string{"name", "foo2"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+			map[int][]testAlert{
+				0: {
+					{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+					{labels: []string{"name", "foo1"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+					{labels: []string{"name", "foo2"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+				},
 			},
 		},
 		{
@@ -223,10 +192,19 @@ func TestAlertingRule_Exec(t *testing.T) {
 			// 1: fire first alert
 			// 2: fire second alert, set first inactive
 			// 3: fire third alert, set second inactive
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}},
-				{labels: []string{"name", "foo1"}, alert: &notifier.Alert{State: notifier.StateInactive}},
-				{labels: []string{"name", "foo2"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+			map[int][]testAlert{
+				0: {
+					{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+				},
+				1: {
+					{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}},
+					{labels: []string{"name", "foo1"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+				},
+				2: {
+					{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}},
+					{labels: []string{"name", "foo1"}, alert: &notifier.Alert{State: notifier.StateInactive}},
+					{labels: []string{"name", "foo2"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+				},
 			},
 		},
 		{
@@ -234,8 +212,8 @@ func TestAlertingRule_Exec(t *testing.T) {
 			[][]datasource.Metric{
 				{metricWithLabels(t, "name", "foo")},
 			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}},
+			map[int][]testAlert{
+				0: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}}},
 			},
 		},
 		{
@@ -244,8 +222,9 @@ func TestAlertingRule_Exec(t *testing.T) {
 				{metricWithLabels(t, "name", "foo")},
 				{metricWithLabels(t, "name", "foo")},
 			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+			map[int][]testAlert{
+				0: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}}},
+				1: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
 			},
 		},
 		{
@@ -253,34 +232,13 @@ func TestAlertingRule_Exec(t *testing.T) {
 			[][]datasource.Metric{
 				{metricWithLabels(t, "name", "foo")},
 				{metricWithLabels(t, "name", "foo")},
-				// empty step to reset and delete pending alerts
+				// empty step to delete pending alerts
 				{},
 			},
-			nil,
-		},
-		{
-			newTestAlertingRule("for-pending=>firing=>inactive", defaultStep),
-			[][]datasource.Metric{
-				{metricWithLabels(t, "name", "foo")},
-				{metricWithLabels(t, "name", "foo")},
-				// empty step to reset pending alerts
-				{},
-			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}},
-			},
-		},
-		{
-			newTestAlertingRule("for-pending=>firing=>inactive=>pending", defaultStep),
-			[][]datasource.Metric{
-				{metricWithLabels(t, "name", "foo")},
-				{metricWithLabels(t, "name", "foo")},
-				// empty step to reset pending alerts
-				{},
-				{metricWithLabels(t, "name", "foo")},
-			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}},
+			map[int][]testAlert{
+				0: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}}},
+				1: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}}},
+				2: {},
 			},
 		},
 		{
@@ -288,13 +246,57 @@ func TestAlertingRule_Exec(t *testing.T) {
 			[][]datasource.Metric{
 				{metricWithLabels(t, "name", "foo")},
 				{metricWithLabels(t, "name", "foo")},
-				// empty step to reset pending alerts
+				// empty step to set alert inactive
 				{},
 				{metricWithLabels(t, "name", "foo")},
 				{metricWithLabels(t, "name", "foo")},
 			},
-			[]testAlert{
-				{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}},
+			map[int][]testAlert{
+				0: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}}},
+				1: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				2: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}}},
+				3: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}}},
+				4: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+			},
+		},
+		{
+			newTestAlertingRuleWithKeepFiring("for-pending=>firing=>keepfiring=>firing", defaultStep, defaultStep),
+			[][]datasource.Metric{
+				{metricWithLabels(t, "name", "foo")},
+				{metricWithLabels(t, "name", "foo")},
+				// empty step to keep firing
+				{},
+				{metricWithLabels(t, "name", "foo")},
+			},
+			map[int][]testAlert{
+				0: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}}},
+				1: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				2: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				3: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+			},
+		},
+		{
+			newTestAlertingRuleWithKeepFiring("for-pending=>firing=>keepfiring=>keepfiring=>inactive=>pending=>firing", defaultStep, 2*defaultStep),
+			[][]datasource.Metric{
+				{metricWithLabels(t, "name", "foo")},
+				{metricWithLabels(t, "name", "foo")},
+				// empty step to keep firing
+				{},
+				// another empty step to keep firing
+				{},
+				// empty step to set alert inactive
+				{},
+				{metricWithLabels(t, "name", "foo")},
+				{metricWithLabels(t, "name", "foo")},
+			},
+			map[int][]testAlert{
+				0: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}}},
+				1: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				2: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				3: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
+				4: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateInactive}}},
+				5: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StatePending}}},
+				6: {{labels: []string{"name", "foo"}, alert: &notifier.Alert{State: notifier.StateFiring}}},
 			},
 		},
 	}
@@ -304,7 +306,7 @@ func TestAlertingRule_Exec(t *testing.T) {
 			fq := &fakeQuerier{}
 			tc.rule.q = fq
 			tc.rule.GroupID = fakeGroup.ID()
-			for _, step := range tc.steps {
+			for i, step := range tc.steps {
 				fq.reset()
 				fq.add(step...)
 				if _, err := tc.rule.Exec(context.TODO(), time.Now(), 0); err != nil {
@@ -312,28 +314,31 @@ func TestAlertingRule_Exec(t *testing.T) {
 				}
 				// artificial delay between applying steps
 				time.Sleep(defaultStep)
-			}
-			if len(tc.rule.alerts) != len(tc.expAlerts) {
-				t.Fatalf("expected %d alerts; got %d", len(tc.expAlerts), len(tc.rule.alerts))
-			}
-			expAlerts := make(map[uint64]*notifier.Alert)
-			for _, ta := range tc.expAlerts {
-				labels := make(map[string]string)
-				for i := 0; i < len(ta.labels); i += 2 {
-					k, v := ta.labels[i], ta.labels[i+1]
-					labels[k] = v
+				if _, ok := tc.expAlerts[i]; !ok {
+					continue
 				}
-				labels[alertNameLabel] = tc.rule.Name
-				h := hash(labels)
-				expAlerts[h] = ta.alert
-			}
-			for key, exp := range expAlerts {
-				got, ok := tc.rule.alerts[key]
-				if !ok {
-					t.Fatalf("expected to have key %d", key)
+				if len(tc.rule.alerts) != len(tc.expAlerts[i]) {
+					t.Fatalf("evalIndex %d: expected %d alerts; got %d", i, len(tc.expAlerts[i]), len(tc.rule.alerts))
 				}
-				if got.State != exp.State {
-					t.Fatalf("expected state %d; got %d", exp.State, got.State)
+				expAlerts := make(map[uint64]*notifier.Alert)
+				for _, ta := range tc.expAlerts[i] {
+					labels := make(map[string]string)
+					for i := 0; i < len(ta.labels); i += 2 {
+						k, v := ta.labels[i], ta.labels[i+1]
+						labels[k] = v
+					}
+					labels[alertNameLabel] = tc.rule.Name
+					h := hash(labels)
+					expAlerts[h] = ta.alert
+				}
+				for key, exp := range expAlerts {
+					got, ok := tc.rule.alerts[key]
+					if !ok {
+						t.Fatalf("evalIndex %d: expected to have key %d", i, key)
+					}
+					if got.State != exp.State {
+						t.Fatalf("evalIndex %d: expected state %d; got %d", i, exp.State, got.State)
+					}
 				}
 			}
 		})
@@ -866,8 +871,8 @@ func TestAlertingRule_Template(t *testing.T) {
 			for hash, expAlert := range tc.expAlerts {
 				gotAlert := tc.rule.alerts[hash]
 				if gotAlert == nil {
-					t.Fatalf("alert %d is missing; labels: %v; annotations: %v",
-						hash, expAlert.Labels, expAlert.Annotations)
+					t.Fatalf("alert %d is missing; labels: %v; annotations: %v", hash, expAlert.Labels, expAlert.Annotations)
+					break
 				}
 				if !reflect.DeepEqual(expAlert.Annotations, gotAlert.Annotations) {
 					t.Fatalf("expected to have annotations %#v; got %#v", expAlert.Annotations, gotAlert.Annotations)
@@ -970,11 +975,18 @@ func newTestRuleWithLabels(name string, labels ...string) *AlertingRule {
 }
 
 func newTestAlertingRule(name string, waitFor time.Duration) *AlertingRule {
-	return &AlertingRule{
+	rule := AlertingRule{
 		Name:         name,
 		For:          waitFor,
 		EvalInterval: waitFor,
 		alerts:       make(map[uint64]*notifier.Alert),
 		state:        newRuleState(10),
 	}
+	return &rule
+}
+
+func newTestAlertingRuleWithKeepFiring(name string, waitFor, keepFiringFor time.Duration) *AlertingRule {
+	rule := newTestAlertingRule(name, waitFor)
+	rule.KeepFiringFor = keepFiringFor
+	return rule
 }

app/vmalert/config/config.go

@@ -5,16 +5,14 @@ import (
 	"fmt"
 	"hash/fnv"
 	"net/url"
-	"os"
-	"path/filepath"
 	"sort"
 	"strings"
 
 	"gopkg.in/yaml.v2"
 
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config/log"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/utils"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/envtemplate"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promutils"
 )
 
@@ -38,7 +36,8 @@ type Group struct {
 	Params url.Values `yaml:"params"`
 	// Headers contains optional HTTP headers added to each rule request
 	Headers []Header `yaml:"headers,omitempty"`
-
+	// NotifierHeaders contains optional HTTP headers sent to notifiers for generated notifications
+	NotifierHeaders []Header `yaml:"notifier_headers,omitempty"`
 	// Catches all undefined fields and must be empty after parsing.
 	XXX map[string]interface{} `yaml:",inline"`
 }
@@ -106,14 +105,16 @@ func (g *Group) Validate(validateTplFn ValidateTplFn, validateExpressions bool)
 // Rule describes entity that represent either
 // recording rule or alerting rule.
 type Rule struct {
-	ID          uint64
-	Record      string              `yaml:"record,omitempty"`
-	Alert       string              `yaml:"alert,omitempty"`
-	Expr        string              `yaml:"expr"`
-	For         *promutils.Duration `yaml:"for,omitempty"`
-	Labels      map[string]string   `yaml:"labels,omitempty"`
-	Annotations map[string]string   `yaml:"annotations,omitempty"`
-	Debug       bool                `yaml:"debug,omitempty"`
+	ID     uint64
+	Record string              `yaml:"record,omitempty"`
+	Alert  string              `yaml:"alert,omitempty"`
+	Expr   string              `yaml:"expr"`
+	For    *promutils.Duration `yaml:"for,omitempty"`
+	// Alert will continue firing for this long even when the alerting expression no longer has results.
+	KeepFiringFor *promutils.Duration `yaml:"keep_firing_for,omitempty"`
+	Labels        map[string]string   `yaml:"labels,omitempty"`
+	Annotations   map[string]string   `yaml:"annotations,omitempty"`
+	Debug         bool                `yaml:"debug,omitempty"`
 	// UpdateEntriesLimit defines max number of rule's state updates stored in memory.
 	// Overrides `-rule.updateEntriesLimit`.
 	UpdateEntriesLimit *int `yaml:"update_entries_limit,omitempty"`
@@ -201,21 +202,45 @@ func (r *Rule) Validate() error {
 // ValidateTplFn must validate the given annotations
 type ValidateTplFn func(annotations map[string]string) error
 
+// cLogger is a logger with support of logs suppressing.
+// it is used when logs emitted by config package needs
+// to be suppressed.
+var cLogger = &log.Logger{}
+
+// ParseSilent parses rule configs from given file patterns without emitting logs
+func ParseSilent(pathPatterns []string, validateTplFn ValidateTplFn, validateExpressions bool) ([]Group, error) {
+	cLogger.Suppress(true)
+	defer cLogger.Suppress(false)
+
+	files, err := readFromFS(pathPatterns)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read from the config: %s", err)
+	}
+	return parse(files, validateTplFn, validateExpressions)
+}
+
 // Parse parses rule configs from given file patterns
 func Parse(pathPatterns []string, validateTplFn ValidateTplFn, validateExpressions bool) ([]Group, error) {
-	var fp []string
-	for _, pattern := range pathPatterns {
-		matches, err := filepath.Glob(pattern)
-		if err != nil {
-			return nil, fmt.Errorf("error reading file pattern %s: %w", pattern, err)
-		}
-		fp = append(fp, matches...)
+	files, err := readFromFS(pathPatterns)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read from the config: %s", err)
 	}
+	groups, err := parse(files, validateTplFn, validateExpressions)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse %s: %s", pathPatterns, err)
+	}
+	if len(groups) < 1 {
+		cLogger.Warnf("no groups found in %s", strings.Join(pathPatterns, ";"))
+	}
+	return groups, nil
+}
+
+func parse(files map[string][]byte, validateTplFn ValidateTplFn, validateExpressions bool) ([]Group, error) {
 	errGroup := new(utils.ErrGroup)
 	var groups []Group
-	for _, file := range fp {
+	for file, data := range files {
 		uniqueGroups := map[string]struct{}{}
-		gr, err := parseFile(file)
+		gr, err := parseConfig(data)
 		if err != nil {
 			errGroup.Add(fmt.Errorf("failed to parse file %q: %w", file, err))
 			continue
@@ -237,20 +262,19 @@ func Parse(pathPatterns []string, validateTplFn ValidateTplFn, validateExpressio
 	if err := errGroup.Err(); err != nil {
 		return nil, err
 	}
-	if len(groups) < 1 {
-		logger.Warnf("no groups found in %s", strings.Join(pathPatterns, ";"))
-	}
+	sort.SliceStable(groups, func(i, j int) bool {
+		if groups[i].File != groups[j].File {
+			return groups[i].File < groups[j].File
+		}
+		return groups[i].Name < groups[j].Name
+	})
 	return groups, nil
 }
 
-func parseFile(path string) ([]Group, error) {
-	data, err := os.ReadFile(path)
+func parseConfig(data []byte) ([]Group, error) {
+	data, err := envtemplate.ReplaceBytes(data)
 	if err != nil {
-		return nil, fmt.Errorf("error reading alert rule file %q: %w", path, err)
-	}
-	data, err = envtemplate.ReplaceBytes(data)
-	if err != nil {
-		return nil, fmt.Errorf("cannot expand environment vars in %q: %w", path, err)
+		return nil, fmt.Errorf("cannot expand environment vars: %w", err)
 	}
 	g := struct {
 		Groups []Group `yaml:"groups"`

app/vmalert/config/config_test.go

@@ -1,6 +1,8 @@
 package config
 
 import (
+	"net/http"
+	"net/http/httptest"
 	"net/url"
 	"os"
 	"strings"
@@ -27,6 +29,40 @@ func TestParseGood(t *testing.T) {
 	}
 }
 
+func TestParseFromURL(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/bad", func(w http.ResponseWriter, _ *http.Request) {
+		w.Write([]byte("foo bar"))
+	})
+	mux.HandleFunc("/good-alert", func(w http.ResponseWriter, _ *http.Request) {
+		w.Write([]byte(`
+groups:
+  - name: TestGroup
+    rules:
+      - alert: Conns
+        expr: vm_tcplistener_conns > 0`))
+	})
+	mux.HandleFunc("/good-rr", func(w http.ResponseWriter, _ *http.Request) {
+		w.Write([]byte(`
+groups:
+  - name: TestGroup
+    rules:
+      - record: conns
+        expr: max(vm_tcplistener_conns)`))
+	})
+
+	srv := httptest.NewServer(mux)
+	defer srv.Close()
+
+	if _, err := Parse([]string{srv.URL + "/good-alert", srv.URL + "/good-rr"}, notifier.ValidateTemplates, true); err != nil {
+		t.Errorf("error parsing URLs %s", err)
+	}
+
+	if _, err := Parse([]string{srv.URL + "/bad"}, notifier.ValidateTemplates, true); err == nil {
+		t.Errorf("expected parsing error: %s", err)
+	}
+}
+
 func TestParseBad(t *testing.T) {
 	testCases := []struct {
 		path   []string
@@ -64,6 +100,10 @@ func TestParseBad(t *testing.T) {
 			[]string{"testdata/dir/rules6-bad.rules"},
 			"missing ':' in header",
 		},
+		{
+			[]string{"http://unreachable-url"},
+			"failed to read",
+		},
 	}
 	for _, tc := range testCases {
 		_, err := Parse(tc.path, notifier.ValidateTemplates, true)
@@ -102,7 +142,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr: "group name must be set",
 		},
 		{
-			group: &Group{Name: "test",
+			group: &Group{
+				Name: "test",
 				Rules: []Rule{
 					{
 						Record: "record",
@@ -113,7 +154,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr: "",
 		},
 		{
-			group: &Group{Name: "test",
+			group: &Group{
+				Name: "test",
 				Rules: []Rule{
 					{
 						Record: "record",
@@ -125,7 +167,8 @@ func TestGroup_Validate(t *testing.T) {
 			validateExpressions: true,
 		},
 		{
-			group: &Group{Name: "test",
+			group: &Group{
+				Name: "test",
 				Rules: []Rule{
 					{
 						Alert: "alert",
@@ -139,7 +182,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr: "",
 		},
 		{
-			group: &Group{Name: "test",
+			group: &Group{
+				Name: "test",
 				Rules: []Rule{
 					{
 						Alert: "alert",
@@ -156,7 +200,8 @@ func TestGroup_Validate(t *testing.T) {
 			validateAnnotations: true,
 		},
 		{
-			group: &Group{Name: "test",
+			group: &Group{
+				Name: "test",
 				Rules: []Rule{
 					{
 						Alert: "alert",
@@ -171,7 +216,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr: "duplicate",
 		},
 		{
-			group: &Group{Name: "test",
+			group: &Group{
+				Name: "test",
 				Rules: []Rule{
 					{Alert: "alert", Expr: "up == 1", Labels: map[string]string{
 						"summary": "{{ value|query }}",
@@ -184,7 +230,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr: "duplicate",
 		},
 		{
-			group: &Group{Name: "test",
+			group: &Group{
+				Name: "test",
 				Rules: []Rule{
 					{Record: "record", Expr: "up == 1", Labels: map[string]string{
 						"summary": "{{ value|query }}",
@@ -197,7 +244,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr: "duplicate",
 		},
 		{
-			group: &Group{Name: "test",
+			group: &Group{
+				Name: "test",
 				Rules: []Rule{
 					{Alert: "alert", Expr: "up == 1", Labels: map[string]string{
 						"summary": "{{ value|query }}",
@@ -210,7 +258,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr: "",
 		},
 		{
-			group: &Group{Name: "test",
+			group: &Group{
+				Name: "test",
 				Rules: []Rule{
 					{Record: "alert", Expr: "up == 1", Labels: map[string]string{
 						"summary": "{{ value|query }}",
@@ -223,7 +272,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr: "",
 		},
 		{
-			group: &Group{Name: "test thanos",
+			group: &Group{
+				Name: "test thanos",
 				Type: NewRawType("thanos"),
 				Rules: []Rule{
 					{Alert: "alert", Expr: "up == 1", Labels: map[string]string{
@@ -235,7 +285,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr:              "unknown datasource type",
 		},
 		{
-			group: &Group{Name: "test graphite",
+			group: &Group{
+				Name: "test graphite",
 				Type: NewGraphiteType(),
 				Rules: []Rule{
 					{Alert: "alert", Expr: "up == 1", Labels: map[string]string{
@@ -247,7 +298,8 @@ func TestGroup_Validate(t *testing.T) {
 			expErr:              "",
 		},
 		{
-			group: &Group{Name: "test prometheus",
+			group: &Group{
+				Name: "test prometheus",
 				Type: NewPrometheusType(),
 				Rules: []Rule{
 					{Alert: "alert", Expr: "up == 1", Labels: map[string]string{
@@ -352,7 +404,7 @@ func TestHashRule(t *testing.T) {
 			true,
 		},
 		{
-			Rule{Alert: "alert", Expr: "up == 1", For: promutils.NewDuration(time.Minute)},
+			Rule{Alert: "alert", Expr: "up == 1", For: promutils.NewDuration(time.Minute), KeepFiringFor: promutils.NewDuration(time.Minute)},
 			Rule{Alert: "alert", Expr: "up == 1"},
 			true,
 		},
@@ -538,6 +590,24 @@ rules:
 `)
 	})
 
+	t.Run("`notifier_headers` change", func(t *testing.T) {
+		f(t, `
+name: TestGroup
+notifier_headers:
+  - "TenantID: foo"
+rules:
+  - alert: foo
+    expr: sum by(job) (up == 1)
+`, `
+name: TestGroup
+notifier_headers:
+  - "TenantID: bar"
+rules:
+  - alert: foo
+    expr: sum by(job) (up == 1)
+`)
+	})
+
 	t.Run("`debug` change", func(t *testing.T) {
 		f(t, `
 name: TestGroup

app/vmalert/config/fs.go

@@ -0,0 +1,111 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config/fslocal"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config/fsurl"
+)
+
+// FS represent a file system abstract for reading files.
+type FS interface {
+	// Init initializes FS.
+	Init() error
+
+	// String must return human-readable representation of FS.
+	String() string
+
+	// List returns the list of file names which will be read via Read fn
+	List() ([]string, error)
+
+	// Read returns a list of read files in form of a map
+	// where key is a file name and value is a content of read file.
+	// Read must be called only after the successful Init call.
+	Read(files []string) (map[string][]byte, error)
+}
+
+var (
+	fsRegistryMu sync.Mutex
+	fsRegistry   = make(map[string]FS)
+)
+
+// readFromFS parses the given path list and inits FS for each item.
+// Once initialed, readFromFS will try to read and return files from each FS.
+// readFromFS returns an error if at least one FS failed to init.
+// The function can be called multiple times but each unique path
+// will be initialed only once.
+//
+// It is allowed to mix different FS types in path list.
+func readFromFS(paths []string) (map[string][]byte, error) {
+	var err error
+	result := make(map[string][]byte)
+	for _, path := range paths {
+		fsRegistryMu.Lock()
+		fs, ok := fsRegistry[path]
+		if !ok {
+			fs, err = newFS(path)
+			if err != nil {
+				fsRegistryMu.Unlock()
+				return nil, fmt.Errorf("error while parsing path %q: %w", path, err)
+			}
+			if err := fs.Init(); err != nil {
+				fsRegistryMu.Unlock()
+				return nil, fmt.Errorf("error while initializing path %q: %w", path, err)
+			}
+			fsRegistry[path] = fs
+		}
+		fsRegistryMu.Unlock()
+
+		list, err := fs.List()
+		if err != nil {
+			return nil, fmt.Errorf("failed to list files from %q", fs)
+		}
+
+		cLogger.Infof("found %d files to read from %q", len(list), fs)
+
+		if len(list) < 1 {
+			continue
+		}
+
+		ts := time.Now()
+		files, err := fs.Read(list)
+		if err != nil {
+			return nil, fmt.Errorf("error while reading files from %q: %w", fs, err)
+		}
+		cLogger.Infof("finished reading %d files in %v from %q", len(list), time.Since(ts), fs)
+
+		for k, v := range files {
+			if _, ok := result[k]; ok {
+				return nil, fmt.Errorf("duplicate found for file name %q: file names must be unique", k)
+			}
+			result[k] = v
+		}
+	}
+	return result, nil
+}
+
+// newFS creates FS based on the give path.
+// Supported file systems are: fs
+func newFS(originPath string) (FS, error) {
+	scheme := "fs"
+	path := originPath
+	n := strings.Index(path, "://")
+	if n >= 0 {
+		scheme = path[:n]
+		path = path[n+len("://"):]
+	}
+	if len(path) == 0 {
+		return nil, fmt.Errorf("path cannot be empty")
+	}
+	switch scheme {
+	case "fs":
+		return &fslocal.FS{Pattern: path}, nil
+	case "http", "https":
+		return &fsurl.FS{Path: originPath}, nil
+	default:
+		return nil, fmt.Errorf("unsupported scheme %q", scheme)
+	}
+}

app/vmalert/config/fs_test.go

@@ -0,0 +1,39 @@
+package config
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestNewFS(t *testing.T) {
+	f := func(path, expStr string) {
+		t.Helper()
+		fs, err := newFS(path)
+		if err != nil {
+			t.Fatalf("unexpected err: %s", err)
+		}
+		if fs.String() != expStr {
+			t.Fatalf("expected FS %q; got %q", expStr, fs.String())
+		}
+	}
+
+	f("/foo/bar", "Local FS{MatchPattern: \"/foo/bar\"}")
+	f("fs:///foo/bar", "Local FS{MatchPattern: \"/foo/bar\"}")
+}
+
+func TestNewFSNegative(t *testing.T) {
+	f := func(path, expErr string) {
+		t.Helper()
+		_, err := newFS(path)
+		if err == nil {
+			t.Fatalf("expected to have err: %s", expErr)
+		}
+		if !strings.Contains(err.Error(), expErr) {
+			t.Fatalf("expected to have err %q; got %q instead", expErr, err)
+		}
+	}
+
+	f("", "path cannot be empty")
+	f("fs://", "path cannot be empty")
+	f("foobar://baz", `unsupported scheme "foobar"`)
+}

app/vmalert/config/fslocal/fslocal.go

@@ -0,0 +1,50 @@
+package fslocal
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/bmatcuk/doublestar/v4"
+)
+
+// FS represents a local file system
+type FS struct {
+	// Pattern is used for matching one or multiple files.
+	// The pattern may describe hierarchical names such as
+	// /usr/*/bin/ed (assuming the Separator is '/').
+	Pattern string
+}
+
+// Init verifies that configured Pattern is correct
+func (fs *FS) Init() error {
+	_, err := doublestar.FilepathGlob(fs.Pattern)
+	return err
+}
+
+// String implements Stringer interface
+func (fs *FS) String() string {
+	return fmt.Sprintf("Local FS{MatchPattern: %q}", fs.Pattern)
+}
+
+// List returns the list of file names which will be read via Read fn
+func (fs *FS) List() ([]string, error) {
+	matches, err := doublestar.FilepathGlob(fs.Pattern)
+	if err != nil {
+		return nil, fmt.Errorf("error while matching files via pattern %s: %w", fs.Pattern, err)
+	}
+	return matches, nil
+}
+
+// Read returns a map of read files where
+// key is the file name and value is file's content.
+func (fs *FS) Read(files []string) (map[string][]byte, error) {
+	result := make(map[string][]byte)
+	for _, path := range files {
+		data, err := os.ReadFile(path)
+		if err != nil {
+			return nil, fmt.Errorf("error while reading file %q: %w", path, err)
+		}
+		result[path] = data
+	}
+	return result, nil
+}

app/vmalert/config/fsurl/url.go

@@ -0,0 +1,57 @@
+package fsurl
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+)
+
+// FS represents a struct which can read content from URL Path
+type FS struct {
+	// Path defines the URL to read the data from
+	Path string
+}
+
+// Init verifies that configured Path is correct
+func (fs *FS) Init() error {
+	_, err := url.Parse(fs.Path)
+	return err
+}
+
+// String implements Stringer interface
+func (fs *FS) String() string {
+	return fmt.Sprintf("URL {Path: %q}", fs.Path)
+}
+
+// List returns the list of file names which will be read via Read fn
+// List isn't supported by FS and reads from Path only
+func (fs *FS) List() ([]string, error) {
+	return []string{fs.Path}, nil
+}
+
+// Read returns a map of read files where
+// key is the file name and value is file's content.
+func (fs *FS) Read(files []string) (map[string][]byte, error) {
+	result := make(map[string][]byte)
+	for _, path := range files {
+		resp, err := http.Get(path)
+		if err != nil {
+			return nil, fmt.Errorf("failed to read from %q: %w", path, err)
+		}
+		data, err := io.ReadAll(resp.Body)
+		_ = resp.Body.Close()
+		if resp.StatusCode != http.StatusOK {
+			if len(data) > 4*1024 {
+				data = data[:4*1024]
+			}
+			return nil, fmt.Errorf("unexpected status code when fetching %q: %d, expecting %d; response: %q",
+				path, resp.StatusCode, http.StatusOK, data)
+		}
+		if err != nil {
+			return nil, fmt.Errorf("cannot read %q: %s", path, err)
+		}
+		result[path] = data
+	}
+	return result, nil
+}

app/vmalert/config/log/logger.go

@@ -0,0 +1,59 @@
+package log
+
+import (
+	"sync"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+)
+
+// Logger is using lib/logger for logging
+// but can be suppressed via Suppress method
+type Logger struct {
+	mu       sync.RWMutex
+	disabled bool
+}
+
+// Suppress whether to ignore message logging.
+// Once suppressed, logging continues to be ignored
+// until logger is un-suppressed.
+func (l *Logger) Suppress(v bool) {
+	l.mu.Lock()
+	l.disabled = v
+	l.mu.Unlock()
+}
+
+func (l *Logger) isDisabled() bool {
+	l.mu.RLock()
+	defer l.mu.RUnlock()
+	return l.disabled
+}
+
+// Errorf logs error message.
+func (l *Logger) Errorf(format string, args ...interface{}) {
+	if l.isDisabled() {
+		return
+	}
+	logger.Errorf(format, args...)
+}
+
+// Warnf logs warning message.
+func (l *Logger) Warnf(format string, args ...interface{}) {
+	if l.isDisabled() {
+		return
+	}
+	logger.Warnf(format, args...)
+}
+
+// Infof logs info message.
+func (l *Logger) Infof(format string, args ...interface{}) {
+	if l.isDisabled() {
+		return
+	}
+	logger.Infof(format, args...)
+}
+
+// Panicf logs panic message and panics.
+// Panicf can't be suppressed
+func (l *Logger) Panicf(format string, args ...interface{}) {
+	logger.Panicf(format, args...)
+}

app/vmalert/config/log/logger_test.go

@@ -0,0 +1,54 @@
+package log
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+)
+
+func TestOutput(t *testing.T) {
+	testOutput := &bytes.Buffer{}
+	logger.SetOutputForTests(testOutput)
+	defer logger.ResetOutputForTest()
+
+	log := &Logger{}
+
+	mustMatch := func(exp string) {
+		t.Helper()
+		if exp == "" {
+			if testOutput.String() != "" {
+				t.Errorf("expected output to be empty; got %q", testOutput.String())
+				return
+			}
+		}
+		if !strings.Contains(testOutput.String(), exp) {
+			t.Errorf("output %q should contain %q", testOutput.String(), exp)
+		}
+		fmt.Println(testOutput.String())
+		testOutput.Reset()
+	}
+
+	log.Warnf("foo")
+	mustMatch("foo")
+
+	log.Infof("info %d", 2)
+	mustMatch("info 2")
+
+	log.Errorf("error %s %d", "baz", 5)
+	mustMatch("error baz 5")
+
+	log.Suppress(true)
+
+	log.Warnf("foo")
+	mustMatch("")
+
+	log.Infof("info %d", 2)
+	mustMatch("")
+
+	log.Errorf("error %q %d", "baz", 5)
+	mustMatch("")
+
+}

app/vmalert/config/testdata/rules/rules2-good.rules

@@ -5,6 +5,8 @@ groups:
     limit: 1000
     headers:
       - "MyHeader: foo"
+    notifier_headers:
+      - "MyHeader: foo"
     params:
       denyPartialResponse: ["true"]
     rules:

app/vmalert/datasource/datasource.go

@@ -1,9 +1,12 @@
 package datasource
 
 import (
+	"bytes"
 	"context"
 	"net/http"
 	"net/url"
+	"sort"
+	"strconv"
 	"time"
 )
 
@@ -13,11 +16,22 @@ type Querier interface {
 	// It returns list of Metric in response, the http.Request used for sending query
 	// and error if any. Returned http.Request can't be reused and its body is already read.
 	// Query should stop once ctx is cancelled.
-	Query(ctx context.Context, query string, ts time.Time) ([]Metric, *http.Request, error)
+	Query(ctx context.Context, query string, ts time.Time) (Result, *http.Request, error)
 	// QueryRange executes range request with the given query on the given time range.
 	// It returns list of Metric in response and error if any.
 	// QueryRange should stop once ctx is cancelled.
-	QueryRange(ctx context.Context, query string, from, to time.Time) ([]Metric, error)
+	QueryRange(ctx context.Context, query string, from, to time.Time) (Result, error)
+}
+
+// Result represents expected response from the datasource
+type Result struct {
+	// Data contains list of received Metric
+	Data []Metric
+	// SeriesFetched contains amount of time series processed by datasource
+	// during query evaluation.
+	// If nil, then this feature is not supported by the datasource.
+	// SeriesFetched is supported by VictoriaMetrics since v1.90.
+	SeriesFetched *int
 }
 
 // QuerierBuilder builds Querier with given params.
@@ -97,3 +111,69 @@ type Label struct {
 	Name  string
 	Value string
 }
+
+// Labels is collection of Label
+type Labels []Label
+
+func (ls Labels) Len() int           { return len(ls) }
+func (ls Labels) Swap(i, j int)      { ls[i], ls[j] = ls[j], ls[i] }
+func (ls Labels) Less(i, j int) bool { return ls[i].Name < ls[j].Name }
+
+func (ls Labels) String() string {
+	var b bytes.Buffer
+
+	b.WriteByte('{')
+	for i, l := range ls {
+		if i > 0 {
+			b.WriteByte(',')
+			b.WriteByte(' ')
+		}
+		b.WriteString(l.Name)
+		b.WriteByte('=')
+		b.WriteString(strconv.Quote(l.Value))
+	}
+	b.WriteByte('}')
+	return b.String()
+}
+
+// LabelCompare return negative if a is less than b, return 0 if they are the same
+// eg.
+// a=[]Label{{Name: "a", Value: "1"}},b=[]Label{{Name: "b", Value: "1"}}, return -1
+// a=[]Label{{Name: "a", Value: "2"}},b=[]Label{{Name: "a", Value: "1"}}, return 1
+// a=[]Label{{Name: "a", Value: "1"}},b=[]Label{{Name: "a", Value: "1"}}, return 0
+func LabelCompare(a, b Labels) int {
+	l := len(a)
+	if len(b) < l {
+		l = len(b)
+	}
+
+	for i := 0; i < l; i++ {
+		if a[i].Name != b[i].Name {
+			if a[i].Name < b[i].Name {
+				return -1
+			}
+			return 1
+		}
+		if a[i].Value != b[i].Value {
+			if a[i].Value < b[i].Value {
+				return -1
+			}
+			return 1
+		}
+	}
+	// if all labels so far were in common, the set with fewer labels comes first.
+	return len(a) - len(b)
+}
+
+// ConvertToLabels convert map to Labels
+func ConvertToLabels(m map[string]string) (labelset Labels) {
+	for k, v := range m {
+		labelset = append(labelset, Label{
+			Name:  k,
+			Value: v,
+		})
+	}
+	// sort label
+	sort.Slice(labelset, func(i, j int) bool { return labelset[i].Name < labelset[j].Name })
+	return
+}

app/vmalert/datasource/init.go

@@ -47,7 +47,7 @@ var (
 		"For example, if -datasource.queryStep=15s then param \"step\" with value \"15s\" will be added to every query. "+
 		"If set to 0, rule's evaluation interval will be used instead.")
 	queryTimeAlignment = flag.Bool("datasource.queryTimeAlignment", true, `Whether to align "time" parameter with evaluation interval.`+
-		"Alignment supposed to produce deterministic results despite of number of vmalert replicas or time they were started. See more details here https://github.com/VictoriaMetrics/VictoriaMetrics/pull/1257")
+		"Alignment supposed to produce deterministic results despite number of vmalert replicas or time they were started. See more details here https://github.com/VictoriaMetrics/VictoriaMetrics/pull/1257")
 	maxIdleConnections = flag.Int("datasource.maxIdleConnections", 100, `Defines the number of idle (keep-alive connections) to each configured datasource. Consider setting this value equal to the value: groups_total * group.concurrency. Too low a value may result in a high number of sockets in TIME_WAIT state.`)
 	disableKeepAlive   = flag.Bool("datasource.disableKeepAlive", false, `Whether to disable long-lived connections to the datasource. `+
 		`If true, disables HTTP keep-alives and will only use the connection to the server for a single HTTP request.`)

app/vmalert/datasource/vm.go

@@ -2,6 +2,7 @@ package datasource
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -28,6 +29,7 @@ func toDatasourceType(s string) datasourceType {
 }
 
 // VMStorage represents vmstorage entity with ability to read and write metrics
+// WARN: when adding a new field, remember to update Clone() method.
 type VMStorage struct {
 	c                *http.Client
 	authCfg          *promauth.Config
@@ -53,29 +55,54 @@ type keyValue struct {
 
 // Clone makes clone of VMStorage, shares http client.
 func (s *VMStorage) Clone() *VMStorage {
-	return &VMStorage{
+	ns := &VMStorage{
 		c:                s.c,
 		authCfg:          s.authCfg,
 		datasourceURL:    s.datasourceURL,
+		appendTypePrefix: s.appendTypePrefix,
 		lookBack:         s.lookBack,
 		queryStep:        s.queryStep,
-		appendTypePrefix: s.appendTypePrefix,
-		dataSourceType:   s.dataSourceType,
+
+		dataSourceType:     s.dataSourceType,
+		evaluationInterval: s.evaluationInterval,
+
+		// init map so it can be populated below
+		extraParams: url.Values{},
+
+		debug: s.debug,
 	}
+	if len(s.extraHeaders) > 0 {
+		ns.extraHeaders = make([]keyValue, len(s.extraHeaders))
+		copy(ns.extraHeaders, s.extraHeaders)
+	}
+	for k, v := range s.extraParams {
+		ns.extraParams[k] = v
+	}
+
+	return ns
 }
 
 // ApplyParams - changes given querier params.
 func (s *VMStorage) ApplyParams(params QuerierParams) *VMStorage {
 	s.dataSourceType = toDatasourceType(params.DataSourceType)
 	s.evaluationInterval = params.EvaluationInterval
-	s.extraParams = params.QueryParams
-	s.debug = params.Debug
+	if params.QueryParams != nil {
+		if s.extraParams == nil {
+			s.extraParams = url.Values{}
+		}
+		for k, vl := range params.QueryParams {
+			for _, v := range vl { // custom query params are prior to default ones
+				s.extraParams.Set(k, v)
+			}
+		}
+	}
 	if params.Headers != nil {
 		for key, value := range params.Headers {
 			kv := keyValue{key: key, value: value}
 			s.extraHeaders = append(s.extraHeaders, kv)
 		}
 	}
+	s.debug = params.Debug
 	return s
 }
 
@@ -94,14 +121,15 @@ func NewVMStorage(baseURL string, authCfg *promauth.Config, lookBack time.Durati
 		lookBack:         lookBack,
 		queryStep:        queryStep,
 		dataSourceType:   datasourcePrometheus,
+		extraParams:      url.Values{},
 	}
 }
 
 // Query executes the given query and returns parsed response
-func (s *VMStorage) Query(ctx context.Context, query string, ts time.Time) ([]Metric, *http.Request, error) {
+func (s *VMStorage) Query(ctx context.Context, query string, ts time.Time) (Result, *http.Request, error) {
 	req, err := s.newRequestPOST()
 	if err != nil {
-		return nil, nil, err
+		return Result{}, nil, err
 	}
 
 	switch s.dataSourceType {
@@ -110,12 +138,12 @@ func (s *VMStorage) Query(ctx context.Context, query string, ts time.Time) ([]Me
 	case datasourceGraphite:
 		s.setGraphiteReqParams(req, query, ts)
 	default:
-		return nil, nil, fmt.Errorf("engine not found: %q", s.dataSourceType)
+		return Result{}, nil, fmt.Errorf("engine not found: %q", s.dataSourceType)
 	}
 
 	resp, err := s.do(ctx, req)
 	if err != nil {
-		return nil, req, err
+		return Result{}, req, err
 	}
 	defer func() {
 		_ = resp.Body.Close()
@@ -132,24 +160,24 @@ func (s *VMStorage) Query(ctx context.Context, query string, ts time.Time) ([]Me
 // QueryRange executes the given query on the given time range.
 // For Prometheus type see https://prometheus.io/docs/prometheus/latest/querying/api/#range-queries
 // Graphite type isn't supported.
-func (s *VMStorage) QueryRange(ctx context.Context, query string, start, end time.Time) ([]Metric, error) {
+func (s *VMStorage) QueryRange(ctx context.Context, query string, start, end time.Time) (res Result, err error) {
 	if s.dataSourceType != datasourcePrometheus {
-		return nil, fmt.Errorf("%q is not supported for QueryRange", s.dataSourceType)
+		return res, fmt.Errorf("%q is not supported for QueryRange", s.dataSourceType)
 	}
 	req, err := s.newRequestPOST()
 	if err != nil {
-		return nil, err
+		return res, err
 	}
 	if start.IsZero() {
-		return nil, fmt.Errorf("start param is missing")
+		return res, fmt.Errorf("start param is missing")
 	}
 	if end.IsZero() {
-		return nil, fmt.Errorf("end param is missing")
+		return res, fmt.Errorf("end param is missing")
 	}
 	s.setPrometheusRangeReqParams(req, query, start, end)
 	resp, err := s.do(ctx, req)
 	if err != nil {
-		return nil, err
+		return res, err
 	}
 	defer func() {
 		_ = resp.Body.Close()
@@ -162,6 +190,11 @@ func (s *VMStorage) do(ctx context.Context, req *http.Request) (*http.Response,
 		logger.Infof("DEBUG datasource request: executing %s request with params %q", req.Method, req.URL.RawQuery)
 	}
 	resp, err := s.c.Do(req.WithContext(ctx))
+	if errors.Is(err, io.EOF) || errors.Is(err, io.ErrUnexpectedEOF) {
+		// something in the middle between client and datasource might be closing
+		// the connection. So we do a one more attempt in hope request will succeed.
+		resp, err = s.c.Do(req.WithContext(ctx))
+	}
 	if err != nil {
 		return nil, fmt.Errorf("error getting response from %s: %w", req.URL.Redacted(), err)
 	}
@@ -174,7 +207,7 @@ func (s *VMStorage) do(ctx context.Context, req *http.Request) (*http.Response,
 }
 
 func (s *VMStorage) newRequestPOST() (*http.Request, error) {
-	req, err := http.NewRequest("POST", s.datasourceURL, nil)
+	req, err := http.NewRequest(http.MethodPost, s.datasourceURL, nil)
 	if err != nil {
 		return nil, err
 	}

app/vmalert/datasource/vm_graphite_api.go

@@ -35,12 +35,12 @@ func (r graphiteResponse) metrics() []Metric {
 	return ms
 }
 
-func parseGraphiteResponse(req *http.Request, resp *http.Response) ([]Metric, error) {
+func parseGraphiteResponse(req *http.Request, resp *http.Response) (Result, error) {
 	r := &graphiteResponse{}
 	if err := json.NewDecoder(resp.Body).Decode(r); err != nil {
-		return nil, fmt.Errorf("error parsing graphite metrics for %s: %w", req.URL.Redacted(), err)
+		return Result{}, fmt.Errorf("error parsing graphite metrics for %s: %w", req.URL.Redacted(), err)
 	}
-	return r.metrics(), nil
+	return Result{Data: r.metrics()}, nil
 }
 
 const (
@@ -54,6 +54,16 @@ func (s *VMStorage) setGraphiteReqParams(r *http.Request, query string, timestam
 	}
 	r.URL.Path += graphitePath
 	q := r.URL.Query()
+	from := "-5min"
+	if s.lookBack > 0 {
+		lookBack := timestamp.Add(-s.lookBack)
+		from = strconv.FormatInt(lookBack.Unix(), 10)
+	}
+	q.Set("from", from)
+	q.Set("format", "json")
+	q.Set("target", query)
+	q.Set("until", "now")
+
 	for k, vs := range s.extraParams {
 		if q.Has(k) { // extraParams are prior to params in URL
 			q.Del(k)
@@ -62,14 +72,6 @@ func (s *VMStorage) setGraphiteReqParams(r *http.Request, query string, timestam
 			q.Add(k, v)
 		}
 	}
-	q.Set("format", "json")
-	q.Set("target", query)
-	from := "-5min"
-	if s.lookBack > 0 {
-		lookBack := timestamp.Add(-s.lookBack)
-		from = strconv.FormatInt(lookBack.Unix(), 10)
-	}
-	q.Set("from", from)
-	q.Set("until", "now")
+
 	r.URL.RawQuery = q.Encode()
 }

app/vmalert/datasource/vm_prom_api.go

@@ -12,6 +12,9 @@ import (
 var (
 	disablePathAppend = flag.Bool("remoteRead.disablePathAppend", false, "Whether to disable automatic appending of '/api/v1/query' path "+
 		"to the configured -datasource.url and -remoteRead.url")
+	disableStepParam = flag.Bool("datasource.disableStepParam", false, "Whether to disable adding 'step' param to the issued instant queries. "+
+		"This might be useful when using vmalert with datasources that do not support 'step' param for instant queries, like Google Managed Prometheus. "+
+		"It is not recommended to enable this flag if you use vmalert with VictoriaMetrics.")
 )
 
 type promResponse struct {
@@ -22,6 +25,10 @@ type promResponse struct {
 		ResultType string          `json:"resultType"`
 		Result     json.RawMessage `json:"result"`
 	} `json:"data"`
+	// Stats supported by VictoriaMetrics since v1.90
+	Stats struct {
+		SeriesFetched *string `json:"seriesFetched,omitempty"`
+	} `json:"stats,omitempty"`
 }
 
 type promInstant struct {
@@ -96,39 +103,54 @@ const (
 	rtVector, rtMatrix, rScalar = "vector", "matrix", "scalar"
 )
 
-func parsePrometheusResponse(req *http.Request, resp *http.Response) ([]Metric, error) {
+func parsePrometheusResponse(req *http.Request, resp *http.Response) (res Result, err error) {
 	r := &promResponse{}
-	if err := json.NewDecoder(resp.Body).Decode(r); err != nil {
-		return nil, fmt.Errorf("error parsing prometheus metrics for %s: %w", req.URL.Redacted(), err)
+	if err = json.NewDecoder(resp.Body).Decode(r); err != nil {
+		return res, fmt.Errorf("error parsing prometheus metrics for %s: %w", req.URL.Redacted(), err)
 	}
 	if r.Status == statusError {
-		return nil, fmt.Errorf("response error, query: %s, errorType: %s, error: %s", req.URL.Redacted(), r.ErrorType, r.Error)
+		return res, fmt.Errorf("response error, query: %s, errorType: %s, error: %s", req.URL.Redacted(), r.ErrorType, r.Error)
 	}
 	if r.Status != statusSuccess {
-		return nil, fmt.Errorf("unknown status: %s, Expected success or error ", r.Status)
+		return res, fmt.Errorf("unknown status: %s, Expected success or error ", r.Status)
 	}
+	var parseFn func() ([]Metric, error)
 	switch r.Data.ResultType {
 	case rtVector:
 		var pi promInstant
 		if err := json.Unmarshal(r.Data.Result, &pi.Result); err != nil {
-			return nil, fmt.Errorf("umarshal err %s; \n %#v", err, string(r.Data.Result))
+			return res, fmt.Errorf("umarshal err %s; \n %#v", err, string(r.Data.Result))
 		}
-		return pi.metrics()
+		parseFn = pi.metrics
 	case rtMatrix:
 		var pr promRange
 		if err := json.Unmarshal(r.Data.Result, &pr.Result); err != nil {
-			return nil, err
+			return res, err
 		}
-		return pr.metrics()
+		parseFn = pr.metrics
 	case rScalar:
 		var ps promScalar
 		if err := json.Unmarshal(r.Data.Result, &ps); err != nil {
-			return nil, err
+			return res, err
 		}
-		return ps.metrics()
+		parseFn = ps.metrics
 	default:
-		return nil, fmt.Errorf("unknown result type %q", r.Data.ResultType)
+		return res, fmt.Errorf("unknown result type %q", r.Data.ResultType)
 	}
+
+	ms, err := parseFn()
+	if err != nil {
+		return res, err
+	}
+	res = Result{Data: ms}
+	if r.Stats.SeriesFetched != nil {
+		intV, err := strconv.Atoi(*r.Stats.SeriesFetched)
+		if err != nil {
+			return res, fmt.Errorf("failed to convert stats.seriesFetched to int: %w", err)
+		}
+		res.SeriesFetched = &intV
+	}
+	return res, nil
 }
 
 func (s *VMStorage) setPrometheusInstantReqParams(r *http.Request, query string, timestamp time.Time) {
@@ -146,13 +168,13 @@ func (s *VMStorage) setPrometheusInstantReqParams(r *http.Request, query string,
 		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1232
 		timestamp = timestamp.Truncate(s.evaluationInterval)
 	}
-	q.Set("time", fmt.Sprintf("%d", timestamp.Unix()))
-	if s.evaluationInterval > 0 { // set step as evaluationInterval by default
+	q.Set("time", timestamp.Format(time.RFC3339))
+	if !*disableStepParam && s.evaluationInterval > 0 { // set step as evaluationInterval by default
 		// always convert to seconds to keep compatibility with older
 		// Prometheus versions. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1943
 		q.Set("step", fmt.Sprintf("%ds", int(s.evaluationInterval.Seconds())))
 	}
-	if s.queryStep > 0 { // override step with user-specified value
+	if !*disableStepParam && s.queryStep > 0 { // override step with user-specified value
 		// always convert to seconds to keep compatibility with older
 		// Prometheus versions. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1943
 		q.Set("step", fmt.Sprintf("%ds", int(s.queryStep.Seconds())))
@@ -169,8 +191,8 @@ func (s *VMStorage) setPrometheusRangeReqParams(r *http.Request, query string, s
 		r.URL.Path += "/api/v1/query_range"
 	}
 	q := r.URL.Query()
-	q.Add("start", fmt.Sprintf("%d", start.Unix()))
-	q.Add("end", fmt.Sprintf("%d", end.Unix()))
+	q.Add("start", start.Format(time.RFC3339))
+	q.Add("end", end.Format(time.RFC3339))
 	if s.evaluationInterval > 0 { // set step as evaluationInterval by default
 		// always convert to seconds to keep compatibility with older
 		// Prometheus versions. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1943

app/vmalert/datasource/vm_test.go

@@ -8,7 +8,6 @@ import (
 	"net/url"
 	"reflect"
 	"sort"
-	"strconv"
 	"strings"
 	"testing"
 	"time"
@@ -35,13 +34,6 @@ func TestVMInstantQuery(t *testing.T) {
 		t.Errorf("should not be called")
 	})
 	c := -1
-	mux.HandleFunc("/render", func(w http.ResponseWriter, request *http.Request) {
-		c++
-		switch c {
-		case 8:
-			w.Write([]byte(`[{"target":"constantLine(10)","tags":{"name":"constantLine(10)"},"datapoints":[[10,1611758343],[10,1611758373],[10,1611758403]]}]`))
-		}
-	})
 	mux.HandleFunc("/api/v1/query", func(w http.ResponseWriter, r *http.Request) {
 		c++
 		if r.Method != http.MethodPost {
@@ -57,27 +49,33 @@ func TestVMInstantQuery(t *testing.T) {
 		if timeParam == "" {
 			t.Errorf("expected 'time' in query param, got nil instead")
 		}
-		if _, err := strconv.ParseInt(timeParam, 10, 64); err != nil {
-			t.Errorf("failed to parse 'time' query param: %s", err)
+		if _, err := time.Parse(time.RFC3339, timeParam); err != nil {
+			t.Errorf("failed to parse 'time' query param %q: %s", timeParam, err)
 		}
 		switch c {
 		case 0:
-			conn, _, _ := w.(http.Hijacker).Hijack()
-			_ = conn.Close()
-		case 1:
 			w.WriteHeader(500)
-		case 2:
+		case 1:
 			w.Write([]byte("[]"))
-		case 3:
+		case 2:
 			w.Write([]byte(`{"status":"error", "errorType":"type:", "error":"some error msg"}`))
-		case 4:
+		case 3:
 			w.Write([]byte(`{"status":"unknown"}`))
-		case 5:
+		case 4:
 			w.Write([]byte(`{"status":"success","data":{"resultType":"matrix"}}`))
-		case 6:
+		case 5:
 			w.Write([]byte(`{"status":"success","data":{"resultType":"vector","result":[{"metric":{"__name__":"vm_rows","foo":"bar"},"value":[1583786142,"13763"]},{"metric":{"__name__":"vm_requests","foo":"baz"},"value":[1583786140,"2000"]}]}}`))
-		case 7:
+		case 6:
 			w.Write([]byte(`{"status":"success","data":{"resultType":"scalar","result":[1583786142, "1"]}}`))
+		case 7:
+			w.Write([]byte(`{"status":"success","data":{"resultType":"scalar","result":[1583786142, "1"]},"stats":{"seriesFetched": "42"}}`))
+		}
+	})
+	mux.HandleFunc("/render", func(w http.ResponseWriter, request *http.Request) {
+		c++
+		switch c {
+		case 8:
+			w.Write([]byte(`[{"target":"constantLine(10)","tags":{"name":"constantLine(10)"},"datapoints":[[10,1611758343],[10,1611758373],[10,1611758403]]}]`))
 		}
 	})
 
@@ -95,24 +93,27 @@ func TestVMInstantQuery(t *testing.T) {
 	ts := time.Now()
 
 	expErr := func(err string) {
-		if _, _, err := pq.Query(ctx, query, ts); err == nil {
+		_, _, gotErr := pq.Query(ctx, query, ts)
+		if gotErr == nil {
 			t.Fatalf("expected %q got nil", err)
 		}
+		if !strings.Contains(gotErr.Error(), err) {
+			t.Fatalf("expected err %q; got %q", err, gotErr)
+		}
 	}
 
-	expErr("connection error")              // 0
-	expErr("invalid response status error") // 1
-	expErr("response body error")           // 2
-	expErr("error status")                  // 3
-	expErr("unknown status")                // 4
-	expErr("non-vector resultType error")   // 5
+	expErr("500")                              // 0
+	expErr("error parsing prometheus metrics") // 1
+	expErr("response error")                   // 2
+	expErr("unknown status")                   // 3
+	expErr("unexpected end of JSON input")     // 4
 
-	m, _, err := pq.Query(ctx, query, ts) // 6 - vector
+	res, _, err := pq.Query(ctx, query, ts) // 5 - vector
 	if err != nil {
 		t.Fatalf("unexpected %s", err)
 	}
-	if len(m) != 2 {
-		t.Fatalf("expected 2 metrics got %d in %+v", len(m), m)
+	if len(res.Data) != 2 {
+		t.Fatalf("expected 2 metrics got %d in %+v", len(res.Data), res.Data)
 	}
 	expected := []Metric{
 		{
@@ -126,17 +127,17 @@ func TestVMInstantQuery(t *testing.T) {
 			Values:     []float64{2000},
 		},
 	}
-	metricsEqual(t, m, expected)
+	metricsEqual(t, res.Data, expected)
 
-	m, req, err := pq.Query(ctx, query, ts) // 7 - scalar
+	res, req, err := pq.Query(ctx, query, ts) // 6 - scalar
 	if err != nil {
 		t.Fatalf("unexpected %s", err)
 	}
 	if req == nil {
 		t.Fatalf("expected request to be non-nil")
 	}
-	if len(m) != 1 {
-		t.Fatalf("expected 1 metrics got %d in %+v", len(m), m)
+	if len(res.Data) != 1 {
+		t.Fatalf("expected 1 metrics got %d in %+v", len(res.Data), res.Data)
 	}
 	expected = []Metric{
 		{
@@ -144,18 +145,44 @@ func TestVMInstantQuery(t *testing.T) {
 			Values:     []float64{1},
 		},
 	}
-	if !reflect.DeepEqual(m, expected) {
-		t.Fatalf("unexpected metric %+v want %+v", m, expected)
+	if !reflect.DeepEqual(res.Data, expected) {
+		t.Fatalf("unexpected metric %+v want %+v", res.Data, expected)
+	}
+
+	if res.SeriesFetched != nil {
+		t.Fatalf("expected `seriesFetched` field to be nil when it is missing in datasource response; got %v instead",
+			res.SeriesFetched)
+	}
+
+	res, _, err = pq.Query(ctx, query, ts) // 7 - scalar with stats
+	if err != nil {
+		t.Fatalf("unexpected %s", err)
+	}
+	if len(res.Data) != 1 {
+		t.Fatalf("expected 1 metrics got %d in %+v", len(res.Data), res)
+	}
+	expected = []Metric{
+		{
+			Timestamps: []int64{1583786142},
+			Values:     []float64{1},
+		},
+	}
+	if !reflect.DeepEqual(res.Data, expected) {
+		t.Fatalf("unexpected metric %+v want %+v", res.Data, expected)
+	}
+	if *res.SeriesFetched != 42 {
+		t.Fatalf("expected `seriesFetched` field to be 42; got %d instead",
+			*res.SeriesFetched)
 	}
 
 	gq := s.BuildWithParams(QuerierParams{DataSourceType: string(datasourceGraphite)})
 
-	m, _, err = gq.Query(ctx, queryRender, ts) // 8 - graphite
+	res, _, err = gq.Query(ctx, queryRender, ts) // 8 - graphite
 	if err != nil {
 		t.Fatalf("unexpected %s", err)
 	}
-	if len(m) != 1 {
-		t.Fatalf("expected 1 metric  got %d in %+v", len(m), m)
+	if len(res.Data) != 1 {
+		t.Fatalf("expected 1 metric  got %d in %+v", len(res.Data), res.Data)
 	}
 	exp := []Metric{
 		{
@@ -164,7 +191,76 @@ func TestVMInstantQuery(t *testing.T) {
 			Values:     []float64{10},
 		},
 	}
-	metricsEqual(t, m, exp)
+	metricsEqual(t, res.Data, exp)
+}
+
+func TestVMInstantQueryWithRetry(t *testing.T) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/", func(_ http.ResponseWriter, _ *http.Request) {
+		t.Errorf("should not be called")
+	})
+	c := -1
+	mux.HandleFunc("/api/v1/query", func(w http.ResponseWriter, r *http.Request) {
+		c++
+		if r.URL.Query().Get("query") != query {
+			t.Errorf("expected %s in query param, got %s", query, r.URL.Query().Get("query"))
+		}
+		switch c {
+		case 0:
+			w.Write([]byte(`{"status":"success","data":{"resultType":"scalar","result":[1583786142, "1"]}}`))
+		case 1:
+			conn, _, _ := w.(http.Hijacker).Hijack()
+			_ = conn.Close()
+		case 2:
+			w.Write([]byte(`{"status":"success","data":{"resultType":"scalar","result":[1583786142, "2"]}}`))
+		case 3:
+			conn, _, _ := w.(http.Hijacker).Hijack()
+			_ = conn.Close()
+		case 4:
+			conn, _, _ := w.(http.Hijacker).Hijack()
+			_ = conn.Close()
+		}
+	})
+
+	srv := httptest.NewServer(mux)
+	defer srv.Close()
+
+	s := NewVMStorage(srv.URL, nil, time.Minute, 0, false, srv.Client())
+	pq := s.BuildWithParams(QuerierParams{DataSourceType: string(datasourcePrometheus)})
+
+	expErr := func(err string) {
+		_, _, gotErr := pq.Query(ctx, query, time.Now())
+		if gotErr == nil {
+			t.Fatalf("expected %q got nil", err)
+		}
+		if !strings.Contains(gotErr.Error(), err) {
+			t.Fatalf("expected err %q; got %q", err, gotErr)
+		}
+	}
+
+	expValue := func(v float64) {
+		res, _, err := pq.Query(ctx, query, time.Now())
+		if err != nil {
+			t.Fatalf("unexpected %s", err)
+		}
+		m := res.Data
+		if len(m) != 1 {
+			t.Fatalf("expected 1 metrics got %d in %+v", len(m), m)
+		}
+		expected := []Metric{
+			{
+				Timestamps: []int64{1583786142},
+				Values:     []float64{v},
+			},
+		}
+		if !reflect.DeepEqual(m, expected) {
+			t.Fatalf("unexpected metric %+v want %+v", m, expected)
+		}
+	}
+
+	expValue(1)   // 0
+	expValue(2)   // 1 - fail, 2 - retry
+	expErr("EOF") // 3, 4 - retries
 }
 
 func metricsEqual(t *testing.T, gotM, expectedM []Metric) {
@@ -211,14 +307,14 @@ func TestVMRangeQuery(t *testing.T) {
 		if startTS == "" {
 			t.Errorf("expected 'start' in query param, got nil instead")
 		}
-		if _, err := strconv.ParseInt(startTS, 10, 64); err != nil {
+		if _, err := time.Parse(time.RFC3339, startTS); err != nil {
 			t.Errorf("failed to parse 'start' query param: %s", err)
 		}
 		endTS := r.URL.Query().Get("end")
 		if endTS == "" {
 			t.Errorf("expected 'end' in query param, got nil instead")
 		}
-		if _, err := strconv.ParseInt(endTS, 10, 64); err != nil {
+		if _, err := time.Parse(time.RFC3339, endTS); err != nil {
 			t.Errorf("failed to parse 'end' query param: %s", err)
 		}
 		step := r.URL.Query().Get("step")
@@ -250,10 +346,11 @@ func TestVMRangeQuery(t *testing.T) {
 
 	start, end := time.Now().Add(-time.Minute), time.Now()
 
-	m, err := pq.QueryRange(ctx, query, start, end)
+	res, err := pq.QueryRange(ctx, query, start, end)
 	if err != nil {
 		t.Fatalf("unexpected %s", err)
 	}
+	m := res.Data
 	if len(m) != 1 {
 		t.Fatalf("expected 1 metric  got %d in %+v", len(m), m)
 	}
@@ -279,6 +376,9 @@ func TestRequestParams(t *testing.T) {
 	}
 	query := "up"
 	timestamp := time.Date(2001, 2, 3, 4, 5, 6, 0, time.UTC)
+	storage := VMStorage{
+		extraParams: url.Values{"round_digits": {"10"}},
+	}
 	testCases := []struct {
 		name       string
 		queryRange bool
@@ -353,8 +453,8 @@ func TestRequestParams(t *testing.T) {
 			false,
 			&VMStorage{},
 			func(t *testing.T, r *http.Request) {
-				exp := fmt.Sprintf("query=%s&time=%d", query, timestamp.Unix())
-				checkEqualString(t, exp, r.URL.RawQuery)
+				exp := url.Values{"query": {query}, "time": {timestamp.Format(time.RFC3339)}}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
 			},
 		},
 		{
@@ -362,8 +462,9 @@ func TestRequestParams(t *testing.T) {
 			true,
 			&VMStorage{},
 			func(t *testing.T, r *http.Request) {
-				exp := fmt.Sprintf("end=%d&query=%s&start=%d", timestamp.Unix(), query, timestamp.Unix())
-				checkEqualString(t, exp, r.URL.RawQuery)
+				ts := timestamp.Format(time.RFC3339)
+				exp := url.Values{"query": {query}, "start": {ts}, "end": {ts}}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
 			},
 		},
 		{
@@ -393,8 +494,8 @@ func TestRequestParams(t *testing.T) {
 				lookBack: time.Minute,
 			},
 			func(t *testing.T, r *http.Request) {
-				exp := fmt.Sprintf("query=%s&time=%d", query, timestamp.Add(-time.Minute).Unix())
-				checkEqualString(t, exp, r.URL.RawQuery)
+				exp := url.Values{"query": {query}, "time": {timestamp.Add(-time.Minute).Format(time.RFC3339)}}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
 			},
 		},
 		{
@@ -406,8 +507,8 @@ func TestRequestParams(t *testing.T) {
 			func(t *testing.T, r *http.Request) {
 				evalInterval := 15 * time.Second
 				tt := timestamp.Truncate(evalInterval)
-				exp := fmt.Sprintf("query=%s&step=%v&time=%d", query, evalInterval, tt.Unix())
-				checkEqualString(t, exp, r.URL.RawQuery)
+				exp := url.Values{"query": {query}, "step": {evalInterval.String()}, "time": {tt.Format(time.RFC3339)}}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
 			},
 		},
 		{
@@ -421,8 +522,8 @@ func TestRequestParams(t *testing.T) {
 				evalInterval := 15 * time.Second
 				tt := timestamp.Add(-time.Minute)
 				tt = tt.Truncate(evalInterval)
-				exp := fmt.Sprintf("query=%s&step=%v&time=%d", query, evalInterval, tt.Unix())
-				checkEqualString(t, exp, r.URL.RawQuery)
+				exp := url.Values{"query": {query}, "step": {evalInterval.String()}, "time": {tt.Format(time.RFC3339)}}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
 			},
 		},
 		{
@@ -432,8 +533,12 @@ func TestRequestParams(t *testing.T) {
 				queryStep: time.Minute,
 			},
 			func(t *testing.T, r *http.Request) {
-				exp := fmt.Sprintf("query=%s&step=%ds&time=%d", query, int(time.Minute.Seconds()), timestamp.Unix())
-				checkEqualString(t, exp, r.URL.RawQuery)
+				exp := url.Values{
+					"query": {query},
+					"step":  {fmt.Sprintf("%ds", int(time.Minute.Seconds()))},
+					"time":  {timestamp.Format(time.RFC3339)},
+				}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
 			},
 		},
 		{
@@ -445,8 +550,8 @@ func TestRequestParams(t *testing.T) {
 			func(t *testing.T, r *http.Request) {
 				evalInterval := 3 * time.Hour
 				tt := timestamp.Truncate(evalInterval)
-				exp := fmt.Sprintf("query=%s&step=%ds&time=%d", query, int(evalInterval.Seconds()), tt.Unix())
-				checkEqualString(t, exp, r.URL.RawQuery)
+				exp := url.Values{"query": {query}, "step": {fmt.Sprintf("%ds", int(evalInterval.Seconds()))}, "time": {tt.Format(time.RFC3339)}}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
 			},
 		},
 		{
@@ -456,8 +561,8 @@ func TestRequestParams(t *testing.T) {
 				extraParams: url.Values{"round_digits": {"10"}},
 			},
 			func(t *testing.T, r *http.Request) {
-				exp := fmt.Sprintf("query=%s&round_digits=10&time=%d", query, timestamp.Unix())
-				checkEqualString(t, exp, r.URL.RawQuery)
+				exp := url.Values{"query": {query}, "round_digits": {"10"}, "time": {timestamp.Format(time.RFC3339)}}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
 			},
 		},
 		{
@@ -470,9 +575,25 @@ func TestRequestParams(t *testing.T) {
 				},
 			},
 			func(t *testing.T, r *http.Request) {
-				exp := fmt.Sprintf("end=%d&max_lookback=1h&nocache=1&query=%s&start=%d",
-					timestamp.Unix(), query, timestamp.Unix())
-				checkEqualString(t, exp, r.URL.RawQuery)
+				exp := url.Values{
+					"query":        {query},
+					"end":          {timestamp.Format(time.RFC3339)},
+					"start":        {timestamp.Format(time.RFC3339)},
+					"nocache":      {"1"},
+					"max_lookback": {"1h"},
+				}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
+			},
+		},
+		{
+			"custom params overrides the original params",
+			false,
+			storage.Clone().ApplyParams(QuerierParams{
+				QueryParams: url.Values{"round_digits": {"2"}},
+			}),
+			func(t *testing.T, r *http.Request) {
+				exp := url.Values{"query": {query}, "round_digits": {"2"}, "time": {timestamp.Format(time.RFC3339)}}
+				checkEqualString(t, exp.Encode(), r.URL.RawQuery)
 			},
 		},
 		{
@@ -490,6 +611,20 @@ func TestRequestParams(t *testing.T) {
 				checkEqualString(t, exp, r.URL.RawQuery)
 			},
 		},
+		{
+			"graphite extra params allows to override from",
+			false,
+			&VMStorage{
+				dataSourceType: datasourceGraphite,
+				extraParams: url.Values{
+					"from": {"-10m"},
+				},
+			},
+			func(t *testing.T, r *http.Request) {
+				exp := fmt.Sprintf("format=json&from=-10m&target=%s&until=now", query)
+				checkEqualString(t, exp, r.URL.RawQuery)
+			},
+		},
 	}
 
 	for _, tc := range testCases {
@@ -514,7 +649,7 @@ func TestRequestParams(t *testing.T) {
 }
 
 func TestHeaders(t *testing.T) {
-	var testCases = []struct {
+	testCases := []struct {
 		name    string
 		vmFn    func() *VMStorage
 		checkFn func(t *testing.T, r *http.Request)
@@ -579,7 +714,8 @@ func TestHeaders(t *testing.T) {
 					authCfg: cfg,
 					extraHeaders: []keyValue{
 						{key: "Authorization", value: "Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ=="},
-					}}
+					},
+				}
 			},
 			checkFn: func(t *testing.T, r *http.Request) {
 				u, p, _ := r.BasicAuth()

app/vmalert/group.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"hash/fnv"
 	"net/url"
@@ -35,15 +36,19 @@ type Group struct {
 	Checksum       string
 	LastEvaluation time.Time
 
-	Labels  map[string]string
-	Params  url.Values
-	Headers map[string]string
+	Labels          map[string]string
+	Params          url.Values
+	Headers         map[string]string
+	NotifierHeaders map[string]string
 
 	doneCh     chan struct{}
 	finishedCh chan struct{}
 	// channel accepts new Group obj
 	// which supposed to update current group
 	updateCh chan *Group
+	// evalCancel stores the cancel fn for interrupting
+	// rules evaluation. Used on groups update() and close().
+	evalCancel context.CancelFunc
 
 	metrics *groupMetrics
 }
@@ -89,16 +94,17 @@ func mergeLabels(groupName, ruleName string, set1, set2 map[string]string) map[s
 
 func newGroup(cfg config.Group, qb datasource.QuerierBuilder, defaultInterval time.Duration, labels map[string]string) *Group {
 	g := &Group{
-		Type:        cfg.Type,
-		Name:        cfg.Name,
-		File:        cfg.File,
-		Interval:    cfg.Interval.Duration(),
-		Limit:       cfg.Limit,
-		Concurrency: cfg.Concurrency,
-		Checksum:    cfg.Checksum,
-		Params:      cfg.Params,
-		Headers:     make(map[string]string),
-		Labels:      cfg.Labels,
+		Type:            cfg.Type,
+		Name:            cfg.Name,
+		File:            cfg.File,
+		Interval:        cfg.Interval.Duration(),
+		Limit:           cfg.Limit,
+		Concurrency:     cfg.Concurrency,
+		Checksum:        cfg.Checksum,
+		Params:          cfg.Params,
+		Headers:         make(map[string]string),
+		NotifierHeaders: make(map[string]string),
+		Labels:          cfg.Labels,
 
 		doneCh:     make(chan struct{}),
 		finishedCh: make(chan struct{}),
@@ -113,6 +119,9 @@ func newGroup(cfg config.Group, qb datasource.QuerierBuilder, defaultInterval ti
 	for _, h := range cfg.Headers {
 		g.Headers[h.Key] = h.Value
 	}
+	for _, h := range cfg.NotifierHeaders {
+		g.NotifierHeaders[h.Key] = h.Value
+	}
 	g.metrics = newGroupMetrics(g)
 	rules := make([]Rule, len(cfg.Rules))
 	for i, r := range cfg.Rules {
@@ -226,6 +235,7 @@ func (g *Group) updateWith(newGroup *Group) error {
 	g.Concurrency = newGroup.Concurrency
 	g.Params = newGroup.Params
 	g.Headers = newGroup.Headers
+	g.NotifierHeaders = newGroup.NotifierHeaders
 	g.Labels = newGroup.Labels
 	g.Limit = newGroup.Limit
 	g.Checksum = newGroup.Checksum
@@ -233,11 +243,24 @@ func (g *Group) updateWith(newGroup *Group) error {
 	return nil
 }
 
+// interruptEval interrupts in-flight rules evaluations
+// within the group. It is expected that g.evalCancel
+// will be repopulated after the call.
+func (g *Group) interruptEval() {
+	g.mu.RLock()
+	defer g.mu.RUnlock()
+
+	if g.evalCancel != nil {
+		g.evalCancel()
+	}
+}
+
 func (g *Group) close() {
 	if g.doneCh == nil {
 		return
 	}
 	close(g.doneCh)
+	g.interruptEval()
 	<-g.finishedCh
 
 	g.metrics.iterationDuration.Unregister()
@@ -251,19 +274,41 @@ func (g *Group) close() {
 
 var skipRandSleepOnGroupStart bool
 
-func (g *Group) start(ctx context.Context, nts func() []notifier.Notifier, rw *remotewrite.Client, rr datasource.QuerierBuilder) {
+func (g *Group) start(ctx context.Context, nts func() []notifier.Notifier, rw remotewrite.RWClient, rr datasource.QuerierBuilder) {
 	defer func() { close(g.finishedCh) }()
 
+	// Spread group rules evaluation over time in order to reduce load on VictoriaMetrics.
+	if !skipRandSleepOnGroupStart {
+		randSleep := uint64(float64(g.Interval) * (float64(g.ID()) / (1 << 64)))
+		sleepOffset := uint64(time.Now().UnixNano()) % uint64(g.Interval)
+		if randSleep < sleepOffset {
+			randSleep += uint64(g.Interval)
+		}
+		randSleep -= sleepOffset
+		sleepTimer := time.NewTimer(time.Duration(randSleep))
+		select {
+		case <-ctx.Done():
+			sleepTimer.Stop()
+			return
+		case <-g.doneCh:
+			sleepTimer.Stop()
+			return
+		case <-sleepTimer.C:
+		}
+	}
+
 	e := &executor{
 		rw:                       rw,
 		notifiers:                nts,
-		previouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label)}
+		notifierHeaders:          g.NotifierHeaders,
+		previouslySentSeriesToRW: make(map[uint64]map[string][]prompbmarshal.Label),
+	}
 
 	evalTS := time.Now()
 
 	logger.Infof("group %q started; interval=%v; concurrency=%d", g.Name, g.Interval, g.Concurrency)
 
-	eval := func(ts time.Time) {
+	eval := func(ctx context.Context, ts time.Time) {
 		g.metrics.iterationTotal.Inc()
 
 		start := time.Now()
@@ -285,7 +330,13 @@ func (g *Group) start(ctx context.Context, nts func() []notifier.Notifier, rw *r
 		g.LastEvaluation = start
 	}
 
-	eval(evalTS)
+	evalCtx, cancel := context.WithCancel(ctx)
+	g.mu.Lock()
+	g.evalCancel = cancel
+	g.mu.Unlock()
+	defer g.evalCancel()
+
+	eval(evalCtx, evalTS)
 
 	t := time.NewTicker(g.Interval)
 	defer t.Stop()
@@ -309,6 +360,14 @@ func (g *Group) start(ctx context.Context, nts func() []notifier.Notifier, rw *r
 			return
 		case ng := <-g.updateCh:
 			g.mu.Lock()
+
+			// it is expected that g.evalCancel will be evoked
+			// somewhere else to unblock group from the rules evaluation.
+			// we recreate the evalCtx and g.evalCancel, so it can
+			// be called again.
+			evalCtx, cancel = context.WithCancel(ctx)
+			g.evalCancel = cancel
+
 			err := g.updateWith(ng)
 			if err != nil {
 				logger.Errorf("group %q: failed to update: %s", g.Name, err)
@@ -319,21 +378,29 @@ func (g *Group) start(ctx context.Context, nts func() []notifier.Notifier, rw *r
 			// ensure that staleness is tracked or existing rules only
 			e.purgeStaleSeries(g.Rules)
 
+			e.notifierHeaders = g.NotifierHeaders
+
 			if g.Interval != ng.Interval {
 				g.Interval = ng.Interval
 				t.Stop()
 				t = time.NewTicker(g.Interval)
+				evalTS = time.Now()
 			}
 			g.mu.Unlock()
 			logger.Infof("group %q re-started; interval=%v; concurrency=%d", g.Name, g.Interval, g.Concurrency)
 		case <-t.C:
 			missed := (time.Since(evalTS) / g.Interval) - 1
+			if missed < 0 {
+				// missed can become < 0 due to irregular delays during evaluation
+				// which can result in time.Since(evalTS) < g.Interval
+				missed = 0
+			}
 			if missed > 0 {
 				g.metrics.iterationMissed.Inc()
 			}
 			evalTS = evalTS.Add((missed + 1) * g.Interval)
 
-			eval(evalTS)
+			eval(evalCtx, evalTS)
 		}
 	}
 }
@@ -352,8 +419,10 @@ func getResolveDuration(groupInterval, delta, maxDuration time.Duration) time.Du
 }
 
 type executor struct {
-	notifiers func() []notifier.Notifier
-	rw        *remotewrite.Client
+	notifiers       func() []notifier.Notifier
+	notifierHeaders map[string]string
+
+	rw remotewrite.RWClient
 
 	previouslySentSeriesToRWMu sync.Mutex
 	// previouslySentSeriesToRW stores series sent to RW on previous iteration
@@ -407,6 +476,11 @@ func (e *executor) exec(ctx context.Context, rule Rule, ts time.Time, resolveDur
 
 	tss, err := rule.Exec(ctx, ts, limit)
 	if err != nil {
+		if errors.Is(err, context.Canceled) {
+			// the context can be cancelled on graceful shutdown
+			// or on group update. So no need to handle the error as usual.
+			return nil
+		}
 		execErrors.Inc()
 		return fmt.Errorf("rule %q: failed to execute: %w", rule, err)
 	}
@@ -448,7 +522,7 @@ func (e *executor) exec(ctx context.Context, rule Rule, ts time.Time, resolveDur
 	for _, nt := range e.notifiers() {
 		wg.Add(1)
 		go func(nt notifier.Notifier) {
-			if err := nt.Send(ctx, alerts); err != nil {
+			if err := nt.Send(ctx, alerts, e.notifierHeaders); err != nil {
 				errGr.Add(fmt.Errorf("rule %q: failed to send alerts to addr %q: %w", rule, nt.Addr(), err))
 			}
 			wg.Done()