app/vmctl: implement migration from mimir object storage

This commit adds the ability to read blocks from Mimir object storage, process
them, and store them in VictoriaMetrics.
This new version of the migration can read Mimir object storage from the
file system and S3, GCP and Azure.

Under the hood, the vmctl tries to read the bucket-index.json file and
collect blocks via the defined filters. Depending on the used path vmctl
decides how to retrieve data. If it is not the file system, it will
download each file from the block and store it in the `tmp` folder.
Process this block folder and remove it from the file system.

Fixes https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7717

.github/workflows/build.yml

@@ -22,8 +22,7 @@ on:
       - '!app/vmui/**'
       - '.github/workflows/build.yml'
 
-permissions:
-  contents: read
+permissions: {}
 
 concurrency:
   cancel-in-progress: true
@@ -32,6 +31,8 @@ concurrency:
 jobs:
   build:
     name: ${{ matrix.os }}-${{ matrix.arch }}
+    permissions:
+      contents: read
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false

.github/workflows/changelog-linter.yml

@@ -5,8 +5,12 @@ on:
     paths:
       - "docs/victoriametrics/changelog/CHANGELOG.md"
 
+permissions: {}
+
 jobs:
   tip-lint:
+    permissions:
+      contents: read
     runs-on: 'ubuntu-latest'
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6.0.2

.github/workflows/check-commit-signed.yml

@@ -3,8 +3,12 @@ name: check-commit-signed
 on:
   pull_request:
 
+permissions: {}
+
 jobs:
   check-commit-signed:
+    permissions:
+      contents: read
     runs-on: ubuntu-latest
     steps:
       - name: Checkout code

.github/workflows/check-licenses.yml

@@ -6,12 +6,14 @@ on:
   pull_request:
     paths:
       - 'vendor'
-permissions:
-  contents: read
+
+permissions: {}
 
 jobs:
   build:
     name: Build
+    permissions:
+      contents: read
     runs-on: ubuntu-latest
     steps:
       - name: Code checkout

.github/workflows/codeql-analysis-go.yml

@@ -18,6 +18,8 @@ concurrency:
   cancel-in-progress: true
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
 
+permissions: {}
+
 jobs:
   analyze:
     name: Analyze

.github/workflows/docs.yaml

@@ -7,12 +7,14 @@ on:
       - 'docs/**'
       - '.github/workflows/docs.yaml'
   workflow_dispatch: {}
-permissions:
-  contents: read  # This is required for actions/checkout and to commit back image update
-  deployments: write
+
+permissions: {}
+
 jobs:
   build:
     name: Build
+    permissions:
+      contents: read
     runs-on: ubuntu-latest
     steps:
       - name: Code checkout

.github/workflows/test.yml

@@ -18,8 +18,7 @@ on:
       - 'go.*'
       - '.github/workflows/main.yml'
 
-permissions:
-  contents: read
+permissions: {}
 
 concurrency:
   cancel-in-progress: true
@@ -29,6 +28,8 @@ concurrency:
 jobs:
   lint:
     name: lint
+    permissions:
+      contents: read
     runs-on: ubuntu-latest
     steps:
       - name: Code checkout
@@ -61,6 +62,8 @@ jobs:
 
   unit:
     name: unit
+    permissions:
+      contents: read
     runs-on: ubuntu-latest
 
     strategy:
@@ -90,6 +93,8 @@ jobs:
 
   apptest:
     name: apptest
+    permissions:
+      contents: read
     runs-on: apptest
 
     steps:

.github/workflows/vmui.yml

@@ -16,11 +16,7 @@ on:
       - 'app/vmui/packages/vmui/**'
       - '.github/workflows/vmui.yml'
 
-permissions:
-  contents: read
-  packages: read
-  pull-requests: read
-  checks: write
+permissions: {}
 
 concurrency:
   cancel-in-progress: true
@@ -29,6 +25,10 @@ concurrency:
 jobs:
   vmui-checks:
     name: VMUI Checks (lint, test, typecheck)
+    permissions:
+      checks: write
+      contents: read
+      pull-requests: read
     runs-on: ubuntu-latest
     steps:
       - name: Code checkout

app/vmagent/remotewrite/remotewrite.go

@@ -79,7 +79,8 @@ var (
 		"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")
+		"This option may be used for improving data compression for the stored metrics. "+
+		"See also -remoteWrite.significantFigures")
 	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. `+
 		`For example, if m{k1="v1",k2="v2"} may be sent as m{k2="v2",k1="v1"}`+

app/vmalert/rule/group.go

@@ -95,6 +95,7 @@ type groupMetrics struct {
 	iterationTotal    *metrics.Counter
 	iterationDuration *metrics.Summary
 	iterationMissed   *metrics.Counter
+	iterationReset    *metrics.Counter
 	iterationInterval *metrics.Gauge
 }
 
@@ -330,6 +331,7 @@ func (g *Group) Init() {
 	g.metrics.iterationTotal = g.metrics.set.NewCounter(fmt.Sprintf(`vmalert_iteration_total{%s}`, labels))
 	g.metrics.iterationDuration = g.metrics.set.NewSummary(fmt.Sprintf(`vmalert_iteration_duration_seconds{%s}`, labels))
 	g.metrics.iterationMissed = g.metrics.set.NewCounter(fmt.Sprintf(`vmalert_iteration_missed_total{%s}`, labels))
+	g.metrics.iterationReset = g.metrics.set.NewCounter(fmt.Sprintf(`vmalert_iteration_reset_total{%s}`, labels))
 	g.metrics.iterationInterval = g.metrics.set.NewGauge(fmt.Sprintf(`vmalert_iteration_interval_seconds{%s}`, labels), func() float64 {
 		i := g.Interval.Seconds()
 		return i
@@ -474,14 +476,16 @@ func (g *Group) Start(ctx context.Context, rw remotewrite.RWClient, rr datasourc
 			if missed < 0 {
 				// missed can become < 0 due to irregular delays during evaluation
 				// which can result in time.Since(evalTS) < g.Interval;
-				// or the system wall clock was changed backward
-				missed = 0
+				// or the system wall clock was changed backward,
+				// Reset the evalTS to the current time.
 				evalTS = time.Now()
+				g.metrics.iterationReset.Inc()
+			} else {
+				evalTS = evalTS.Add((missed + 1) * g.Interval)
 			}
 			if missed > 0 {
 				g.metrics.iterationMissed.Inc()
 			}
-			evalTS = evalTS.Add((missed + 1) * g.Interval)
 
 			eval(evalCtx, evalTS)
 		}

app/vmalert/web.go

@@ -11,6 +11,8 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/VictoriaMetrics/metricsql"
+
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
@@ -160,12 +162,12 @@ func (rh *requestHandler) handler(w http.ResponseWriter, r *http.Request) bool {
 
 	case "/vmalert/api/v1/alerts", "/api/v1/alerts":
 		// path used by Grafana for ng alerting
-		gf, err := newGroupsFilter(r)
+		af, err := newAlertsFilter(r)
 		if err != nil {
 			errJson(w, r, err)
 			return true
 		}
-		data, err := rh.listAlerts(gf)
+		data, err := rh.listAlerts(af)
 		if err != nil {
 			errJson(w, r, err)
 			return true
@@ -325,6 +327,48 @@ func (gf *groupsFilter) matches(group *rule.Group) bool {
 	return true
 }
 
+type alertsFilter struct {
+	gf    *groupsFilter
+	match [][]metricsql.LabelFilter
+}
+
+func getMatchFilters(matches []string) ([][]metricsql.LabelFilter, *httpserver.ErrorWithStatusCode) {
+	if len(matches) == 0 {
+		return nil, nil
+	}
+	tfss := make([][]metricsql.LabelFilter, 0, len(matches))
+	for _, s := range matches {
+		expr, err := metricsql.Parse(s)
+		if err != nil {
+			return nil, errResponse(fmt.Errorf(`invalid parameter "match[]": failed to parse %q: %w`, s, err), http.StatusBadRequest)
+		}
+		me, ok := expr.(*metricsql.MetricExpr)
+		if !ok {
+			return nil, errResponse(fmt.Errorf(`invalid parameter "match[]": expecting metricSelector; got %q`, expr.AppendString(nil)), http.StatusBadRequest)
+		}
+		if len(me.LabelFilterss) == 0 {
+			return nil, errResponse(fmt.Errorf(`invalid parameter "match[]": labelFilterss cannot be empty`), http.StatusBadRequest)
+		}
+		tfss = append(tfss, me.LabelFilterss...)
+	}
+	return tfss, nil
+}
+
+func newAlertsFilter(r *http.Request) (*alertsFilter, *httpserver.ErrorWithStatusCode) {
+	gf, err := newGroupsFilter(r)
+	if err != nil {
+		return nil, err
+	}
+
+	var af alertsFilter
+	af.gf = gf
+	af.match, err = getMatchFilters(r.Form["match[]"])
+	if err != nil {
+		return nil, err
+	}
+	return &af, nil
+}
+
 // see https://prometheus.io/docs/prometheus/latest/querying/api/#rules
 type rulesFilter struct {
 	gf             *groupsFilter
@@ -335,6 +379,7 @@ type rulesFilter struct {
 	maxGroups      int
 	pageNum        int
 	search         string
+	match          [][]metricsql.LabelFilter
 	extendedStates bool
 }
 
@@ -355,7 +400,10 @@ func newRulesFilter(r *http.Request) (*rulesFilter, *httpserver.ErrorWithStatusC
 			return nil, errResponse(fmt.Errorf(`invalid parameter "type": not supported value %q`, ruleTypeParam), http.StatusBadRequest)
 		}
 	}
-
+	rf.match, err = getMatchFilters(r.Form["match[]"])
+	if err != nil {
+		return nil, err
+	}
 	states := vs["state"]
 	if len(states) == 0 {
 		states = vs["filter"]
@@ -416,12 +464,47 @@ func (rf *rulesFilter) matchesRule(r *rule.ApiRule) bool {
 	if len(rf.ruleNames) > 0 && !slices.Contains(rf.ruleNames, r.Name) {
 		return false
 	}
+	if !areLabelsMatch(r.Labels, rf.match) {
+		return false
+	}
 	if len(rf.states) == 0 {
 		return true
 	}
 	return slices.Contains(rf.states, r.State)
 }
 
+func areLabelsMatch(labels map[string]string, matches [][]metricsql.LabelFilter) bool {
+	if len(matches) == 0 {
+		return true
+	}
+	// labels need to match at least one of the provided match[] arg
+	return slices.ContainsFunc(matches, func(filters []metricsql.LabelFilter) bool {
+		for _, mf := range filters {
+			if !isLabelFilterMatch(labels[mf.Label], mf) {
+				return false
+			}
+		}
+		return true
+	})
+}
+
+func isLabelFilterMatch(s string, match metricsql.LabelFilter) bool {
+	if !match.IsRegexp {
+		if match.IsNegative {
+			return s != match.Value
+		}
+		return s == match.Value
+	}
+	re, err := metricsql.CompileRegexpAnchored(match.Value)
+	if err != nil {
+		return false
+	}
+	if match.IsNegative {
+		return !re.MatchString(s)
+	}
+	return re.MatchString(s)
+}
+
 func (rh *requestHandler) groups(rf *rulesFilter) *listGroupsResponse {
 	rh.m.groupsMu.RLock()
 	defer rh.m.groupsMu.RUnlock()
@@ -543,14 +626,14 @@ func (rh *requestHandler) groupAlerts() []rule.GroupAlerts {
 	return gAlerts
 }
 
-func (rh *requestHandler) listAlerts(gf *groupsFilter) ([]byte, *httpserver.ErrorWithStatusCode) {
+func (rh *requestHandler) listAlerts(af *alertsFilter) ([]byte, *httpserver.ErrorWithStatusCode) {
 	rh.m.groupsMu.RLock()
 	defer rh.m.groupsMu.RUnlock()
 
 	lr := listAlertsResponse{Status: "success"}
 	lr.Data.Alerts = make([]*rule.ApiAlert, 0)
 	for _, group := range rh.m.groups {
-		if !gf.matches(group) {
+		if !af.gf.matches(group) {
 			continue
 		}
 		g := group.ToAPI()
@@ -558,7 +641,11 @@ func (rh *requestHandler) listAlerts(gf *groupsFilter) ([]byte, *httpserver.Erro
 			if r.Type != rule.TypeAlerting {
 				continue
 			}
-			lr.Data.Alerts = append(lr.Data.Alerts, r.Alerts...)
+			for _, alert := range r.Alerts {
+				if areLabelsMatch(alert.Labels, af.match) {
+					lr.Data.Alerts = append(lr.Data.Alerts, alert)
+				}
+			}
 		}
 	}
 

app/vmalert/web.qtpl

@@ -348,7 +348,7 @@
                 typeK, ns := keys[i], targets[notifier.TargetType(keys[i])]
                 count := len(ns)
             %}
-            <div class="w-100 flex-column vm-group">
+            <div class="w-100 flex-column">
                 <span class="d-flex justify-content-between" id="group-{%s typeK %}">
                     <a href="#group-{%s typeK %}">{%s typeK %} ({%d count %})</a>
                     <span
@@ -361,7 +361,7 @@
                 <div id="item-{%s typeK %}" class="collapse show">
                     <table class="table table-striped table-hover table-sm">
                         <thead>
-                            <tr class="vm-item">
+                            <tr>
                                 <th scope="col">Labels</th>
                                 <th scope="col">Address</th>
                             </tr>

app/vmalert/web.qtpl.go

@@ -1115,7 +1115,7 @@ func StreamListTargets(qw422016 *qt422016.Writer, r *http.Request, targets map[n
 
 //line app/vmalert/web.qtpl:350
 			qw422016.N().S(`
-            <div class="w-100 flex-column vm-group">
+            <div class="w-100 flex-column">
                 <span class="d-flex justify-content-between" id="group-`)
 //line app/vmalert/web.qtpl:352
 			qw422016.E().S(typeK)
@@ -1152,7 +1152,7 @@ func StreamListTargets(qw422016 *qt422016.Writer, r *http.Request, targets map[n
 			qw422016.N().S(`" class="collapse show">
                     <table class="table table-striped table-hover table-sm">
                         <thead>
-                            <tr class="vm-item">
+                            <tr>
                                 <th scope="col">Labels</th>
                                 <th scope="col">Address</th>
                             </tr>

app/vmalert/web_test.go

@@ -10,6 +10,8 @@ import (
 	"testing"
 	"time"
 
+	"github.com/VictoriaMetrics/metricsql"
+
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
@@ -37,12 +39,14 @@ func TestHandler(t *testing.T) {
 			Concurrency: 1,
 			Rules: []config.Rule{
 				{
-					ID:    0,
-					Alert: "alert",
+					ID:     0,
+					Alert:  "alert",
+					Labels: map[string]string{"job": "foo"},
 				},
 				{
 					ID:     1,
 					Record: "record",
+					Labels: map[string]string{"job": "bar"},
 				},
 			},
 		}, fq, 1*time.Minute, nil)
@@ -128,6 +132,18 @@ func TestHandler(t *testing.T) {
 		if length := len(lr.Data.Alerts); length != 2 {
 			t.Fatalf("expected 2 alert got %d", length)
 		}
+
+		lr = listAlertsResponse{}
+		getResp(t, ts.URL+`/api/v1/alerts?match[]={job="foo"}`, &lr, 200)
+		if length := len(lr.Data.Alerts); length != 3 {
+			t.Fatalf("expected 3 alerts got %d", length)
+		}
+
+		lr = listAlertsResponse{}
+		getResp(t, ts.URL+`/api/v1/alerts?match[]={job="bar"}`, &lr, 200)
+		if length := len(lr.Data.Alerts); length != 0 {
+			t.Fatalf("expected 0 alerts got %d", length)
+		}
 	})
 	t.Run("/api/v1/alert?alertID&groupID", func(t *testing.T) {
 		expAlert := rule.NewAlertAPI(ar, ar.GetAlerts()[0])
@@ -242,6 +258,13 @@ func TestHandler(t *testing.T) {
 		check("/vmalert/api/v1/rules?datasource_type=graphite", 200, 1, 2)
 		check("/vmalert/api/v1/rules?datasource_type=graphiti", 400, 0, 0)
 
+		// invalid match[] params
+		check(`/vmalert/api/v1/rules?match[]={job=!"foo"}`, 400, 0, 0)
+		check(`/vmalert/api/v1/rules?match[]={job="foo"}`, 200, 3, 3)
+		check(`/vmalert/api/v1/rules?match[]={job="bar"}`, 200, 3, 3)
+		check(`/vmalert/api/v1/rules?match[]={job="bar"}&match[]={job="foo"}`, 200, 3, 6)
+		check(`/vmalert/api/v1/rules?match[]={job="barzz"}`, 200, 0, 0)
+
 		// no filtering expected due to bad params
 		check("/api/v1/rules?type=badParam", 400, 0, 0)
 		check("/api/v1/rules?foo=bar", 200, 3, 6)
@@ -367,3 +390,116 @@ func TestEmptyResponse(t *testing.T) {
 		}
 	})
 }
+
+func TestMatchesRule(t *testing.T) {
+	parseMatch := func(t *testing.T, selectors []string) [][]metricsql.LabelFilter {
+		t.Helper()
+		var match [][]metricsql.LabelFilter
+		for _, s := range selectors {
+			expr, err := metricsql.Parse(s)
+			if err != nil {
+				t.Fatalf("failed to parse selector %q: %v", s, err)
+			}
+			me, ok := expr.(*metricsql.MetricExpr)
+			if !ok {
+				t.Fatalf("expected MetricExpr for %q, got %T", s, expr)
+			}
+			match = append(match, me.LabelFilterss...)
+		}
+		return match
+	}
+
+	f := func(t *testing.T, selectors []string, labels map[string]string, wantMatch bool) {
+		t.Helper()
+		rf := &rulesFilter{
+			gf:    &groupsFilter{},
+			match: parseMatch(t, selectors),
+		}
+		r := &rule.ApiRule{Labels: labels}
+		got := rf.matchesRule(r)
+		if got != wantMatch {
+			t.Fatalf("matchesRule(%v) with selectors %v: got %v, want %v",
+				labels, selectors, got, wantMatch)
+		}
+	}
+
+	f(t, nil, map[string]string{"foo": "bar"}, true)
+
+	f(t, []string{`{foo="bar"}`}, map[string]string{"foo": "bar"}, true)
+	f(t, []string{`{foo="bar"}`}, map[string]string{"foo": "baz"}, false)
+
+	f(t, []string{`{foo="bar"}`}, map[string]string{"bar": "baz"}, false)
+	f(t, []string{`{foo=""}`}, map[string]string{"bar": "baz"}, true)
+
+	f(t, []string{`{foo!="bar"}`}, map[string]string{"foo": "baz"}, true)
+	f(t, []string{`{foo!="bar"}`}, map[string]string{"foo": "bar"}, false)
+
+	f(t, []string{`{foo=~"bar.*"}`}, map[string]string{"foo": "bar"}, true)
+	f(t, []string{`{foo=~"bar.*"}`}, map[string]string{"foo": "baz"}, false)
+	f(t, []string{`{bar=~"baz|bar"}`}, map[string]string{"bar": "baz"}, true)
+	f(t, []string{`{bar=~"baz|bar"}`}, map[string]string{"bar": "bar"}, true)
+	f(t, []string{`{bar=~"baz|bar"}`}, map[string]string{"bar": "foo"}, false)
+
+	f(t, []string{`{foo!~"bar.*"}`}, map[string]string{"foo": "baz"}, true)
+	f(t, []string{`{foo!~"bar.*"}`}, map[string]string{"foo": "bar"}, false)
+
+	// single match[] with multiple filters
+	f(t,
+		[]string{`{job="foo",instance="bar"}`},
+		map[string]string{"job": "foo", "instance": "bar"},
+		true,
+	)
+	f(t,
+		[]string{`{job="foo",instance="bar"}`},
+		map[string]string{"job": "other", "instance": "bar"},
+		false,
+	)
+
+	f(t,
+		[]string{`{foo="bar",baz=~"b.*"}`},
+		map[string]string{"foo": "bar", "baz": "bazinga"},
+		true,
+	)
+	f(t,
+		[]string{`{foo="bar",baz=~"b.*"}`},
+		map[string]string{"foo": "other", "baz": "bazinga"},
+		false,
+	)
+
+	// multiple matches[]
+	f(t,
+		[]string{`{foo="bar"}`, `{foo="baz"}`},
+		map[string]string{"foo": "baz"},
+		true,
+	)
+	f(t,
+		[]string{`{foo="bar"}`, `{foo="baz"}`},
+		map[string]string{"foo": "unknown"},
+		false,
+	)
+	f(t,
+		[]string{`{foo=~"bar.*"}`, `{bar=~"baz.*"}`},
+		map[string]string{"bar": "bazinga"},
+		true,
+	)
+	f(t,
+		[]string{`{foo=~"bar.*"}`, `{bar=~"baz.*"}`},
+		map[string]string{"foo": "bartender"},
+		true,
+	)
+	f(t,
+		[]string{`{foo=~"bar.*"}`, `{bar=~"baz.*"}`},
+		map[string]string{"foo": "other", "bar": "other"},
+		false,
+	)
+	f(t,
+		[]string{`{job="foo",instance="bar"}`, `{foo="bar"}`},
+		map[string]string{"foo": "bar"},
+		true,
+	)
+	f(t,
+		[]string{`{job="foo", instance="bar"}`, `{foo="bar"}`},
+		map[string]string{"instance": "barr", "job": "foo"},
+		false,
+	)
+}

app/vmctl/flags.go

@@ -146,7 +146,8 @@ var (
 			Name:  vmRoundDigits,
 			Value: 100,
 			Usage: "Round metric values to the given number of decimal digits after the point. " +
-				"This option may be used for increasing on-disk compression level for the stored metrics",
+				"This option may be used for increasing on-disk compression level for the stored metrics. " +
+				"See also --vm-significant-figures option",
 		},
 		&cli.StringSliceFlag{
 			Name:  vmExtraLabel,
@@ -500,6 +501,96 @@ var (
 	}
 )
 
+const (
+	mimirPath             = "mimir-path"
+	mimirTenantID         = "mimir-tenant-id"
+	mimirConcurrency      = "mimir-concurrency"
+	mimirFilterTimeStart  = "mimir-filter-time-start"
+	mimirFilterTimeEnd    = "mimir-filter-time-end"
+	mimirFilterLabel      = "mimir-filter-label"
+	mimirFilterLabelValue = "mimir-filter-label-value"
+
+	mimirCredsFilePath           = "mimir-creds-file-path"
+	mimirConfigFilePath          = "mimir-config-file-path"
+	mimirConfigProfile           = "mimir-config-profile"
+	mimirCustomS3Endpoint        = "mimir-custom-s3-endpoint"
+	mimirS3ForcePathStyle        = "mimir-s3-force-path-style"
+	mimirS3TLSInsecureSkipVerify = "mimir-s3-tls-insecure-skip-verify"
+	mimirSSEKMSKeyID             = "mimir-s3-sse-kms-key-id"
+	mimirSSEAlgorithm            = "mimir-s3-sse-algorithm"
+)
+
+var (
+	mimirFlags = []cli.Flag{
+		&cli.StringFlag{
+			Name:     mimirPath,
+			Usage:    "Path to Mimir storage bucket or local folder.",
+			Required: true,
+		},
+		&cli.StringFlag{
+			Name:  mimirTenantID,
+			Usage: "Tenant ID for Mimir storage",
+		},
+		&cli.IntFlag{
+			Name:  mimirConcurrency,
+			Usage: "Number of concurrently running block readers",
+			Value: 1,
+		},
+		&cli.StringFlag{
+			Name:     mimirFilterTimeStart,
+			Usage:    "The time filter in RFC3339 format to select timeseries with timestamp equal or higher than provided value. E.g. '2020-01-01T20:07:00Z'",
+			Required: true,
+		},
+		&cli.StringFlag{
+			Name:     mimirFilterTimeEnd,
+			Usage:    "The time filter in RFC3339 format to select timeseries with timestamp equal or lower than provided value. E.g. '2020-01-01T20:07:00Z'",
+			Required: true,
+		},
+		&cli.StringFlag{
+			Name:  mimirFilterLabel,
+			Usage: "Mimir label name to filter timeseries by. E.g. '__name__' will filter timeseries by name.",
+		},
+		&cli.StringFlag{
+			Name:  mimirFilterLabelValue,
+			Usage: fmt.Sprintf("Regular expression to filter label from %q flag.", mimirFilterLabel),
+			Value: ".*",
+		},
+		&cli.StringFlag{
+			Name:  mimirCredsFilePath,
+			Usage: "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",
+		},
+		&cli.StringFlag{
+			Name:  mimirConfigFilePath,
+			Usage: "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",
+		},
+		&cli.StringFlag{
+			Name:  mimirConfigProfile,
+			Usage: "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",
+		},
+		&cli.StringFlag{
+			Name:  mimirCustomS3Endpoint,
+			Usage: "Custom S3 endpoint for use with S3-compatible storages (e.g. MinIO). S3 is used if not set",
+		},
+		&cli.BoolFlag{
+			Name:  mimirS3ForcePathStyle,
+			Usage: "Prefixing endpoint with bucket name when set false, true by default.",
+			Value: true,
+		},
+		&cli.BoolFlag{
+			Name:  mimirS3TLSInsecureSkipVerify,
+			Usage: "Whether to skip TLS verification when connecting to the S3 endpoint.",
+		},
+		&cli.StringFlag{
+			Name:  mimirSSEKMSKeyID,
+			Usage: "SSE KMS Key ID for use with S3-compatible storages.",
+		},
+		&cli.StringFlag{
+			Name:  mimirSSEAlgorithm,
+			Usage: "SSE algorithm for use with S3-compatible storages.",
+		},
+	}
+)
+
 const (
 	vmNativeFilterMatch       = "vm-native-filter-match"
 	vmNativeFilterTimeStart   = "vm-native-filter-time-start"

app/vmctl/main.go

@@ -18,6 +18,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/auth"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/backoff"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/barpool"
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/mimir"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/native"
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/remoteread"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
@@ -297,12 +298,12 @@ func main() {
 				},
 			},
 			{
-				Name:   "thanos",
-				Usage:  "Migrate time series from Thanos blocks (supports raw and downsampled data)",
-				Flags:  mergeFlags(globalFlags, thanosFlags, vmFlags),
+				Name:   "mimir",
+				Usage:  "Migrate time series from Mimir object storage or local filesystem",
+				Flags:  mergeFlags(globalFlags, mimirFlags, vmFlags),
 				Before: beforeFn,
 				Action: func(c *cli.Context) error {
-					fmt.Println("Thanos import mode")
+					fmt.Println("Mimir import mode")
 
 					vmCfg, err := initConfigVM(c)
 					if err != nil {
@@ -314,6 +315,54 @@ func main() {
 						return fmt.Errorf("failed to create VM importer: %s", err)
 					}
 
+					mCfg := mimir.Config{
+						Filter: mimir.Filter{
+							TimeMin:    c.String(mimirFilterTimeStart),
+							TimeMax:    c.String(mimirFilterTimeEnd),
+							Label:      c.String(mimirFilterLabel),
+							LabelValue: c.String(mimirFilterLabelValue),
+						},
+						Path:                    c.String(mimirPath),
+						TenantID:                c.String(mimirTenantID),
+						CredsFilePath:           c.String(mimirCredsFilePath),
+						ConfigFilePath:          c.String(mimirConfigFilePath),
+						ConfigProfile:           c.String(mimirConfigProfile),
+						CustomS3Endpoint:        c.String(mimirCustomS3Endpoint),
+						S3ForcePathStyle:        c.Bool(mimirS3ForcePathStyle),
+						S3TLSInsecureSkipVerify: c.Bool(mimirS3TLSInsecureSkipVerify),
+						SSEKMSKeyID:             c.String(mimirSSEKMSKeyID),
+						SSEAlgorithm:            c.String(mimirSSEAlgorithm),
+					}
+					cl, err := mimir.NewClient(ctx, mCfg)
+					if err != nil {
+						return fmt.Errorf("failed to create mimir client: %s", err)
+					}
+
+					pp := prometheusProcessor{
+						cl:        cl,
+						im:        importer,
+						cc:        c.Int(mimirConcurrency),
+						isVerbose: c.Bool(globalVerbose),
+					}
+					return pp.run(ctx)
+				},
+			},
+			{
+				Name:   "thanos",
+				Usage:  "Migrate time series from Thanos blocks (supports raw and downsampled data)",
+				Flags:  mergeFlags(globalFlags, thanosFlags, vmFlags),
+				Before: beforeFn,
+				Action: func(c *cli.Context) error {
+					fmt.Println("Thanos import mode")
+					vmCfg, err := initConfigVM(c)
+					if err != nil {
+						return fmt.Errorf("failed to init VM configuration: %s", err)
+					}
+
+					importer, err = vm.NewImporter(ctx, vmCfg)
+					if err != nil {
+						return fmt.Errorf("failed to create VM importer: %s", err)
+					}
 					thanosCfg := thanos.Config{
 						Snapshot: c.String(thanosSnapshot),
 						Filter: thanos.Filter{

app/vmctl/mimir/lazyreader.go

@@ -0,0 +1,195 @@
+package mimir
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+	"sync"
+
+	"github.com/oklog/ulid/v2"
+	"github.com/prometheus/prometheus/tsdb"
+	"github.com/prometheus/prometheus/tsdb/tombstones"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/backup/common"
+)
+
+var _ tsdb.BlockReader = (*lazyBlockReader)(nil)
+
+// lazyBlockReader is stores block id and segment num information.
+// It is used to lazily fetch and parse block data.
+// It implements tsdb.BlockReader interface.
+type lazyBlockReader struct {
+	// Block ID.
+	ID ulid.ULID
+	// SegmentsNum stores the number of chunks segments in the block.
+	SegmentsNum int
+
+	mu          sync.Mutex
+	reader      *tsdb.Block
+	tempDirPath string
+	fs          common.RemoteFS
+	err         error
+}
+
+// newLazyBlockReader returns a new LazyBlockReader for the given block.
+func newLazyBlockReader(block *Block, fs common.RemoteFS) (*lazyBlockReader, error) {
+	if block.SegmentsFormat != "1b6d" {
+		return nil, fmt.Errorf("unsupported segments format: %s", block.SegmentsFormat)
+	}
+
+	return &lazyBlockReader{
+		ID:          block.ID,
+		SegmentsNum: block.SegmentsNum,
+		fs:          fs,
+	}, nil
+}
+
+func (lbr *lazyBlockReader) initialize() error {
+	lbr.mu.Lock()
+	defer lbr.mu.Unlock()
+	if lbr.reader != nil {
+		return nil
+	}
+	// fetching block and parse it and store it in lbr.reader
+	temp, err := lbr.mkTempDir()
+	if err != nil {
+		return fmt.Errorf("failed to create temp dir: %s", err)
+	}
+
+	lbr.tempDirPath = temp
+
+	// TODO: replace fetchFile and writeFile with buffered IO if needed
+	meta, err := lbr.fetchFile(metaFilename)
+	if err != nil {
+		return err
+	}
+	if err := lbr.writeFile(temp, metaFilename, meta); err != nil {
+		return fmt.Errorf("failed to write meta file: %w", err)
+	}
+	idx, err := lbr.fetchFile(indexFilename)
+	if err != nil {
+		return fmt.Errorf("failed to fetch index file %q: %w", indexFilename, err)
+	}
+	if err := lbr.writeFile(temp, indexFilename, idx); err != nil {
+		return err
+	}
+
+	for i := 1; i <= lbr.SegmentsNum; i++ {
+		// segments formats has format 1b06d
+		// https://github.com/grafana/mimir/blob/main/pkg/storage/tsdb/bucketindex/index.go#L32
+		chunkName := fmt.Sprintf("%06d", i)
+		blockChunkPath := filepath.Join("chunks", chunkName)
+		chunk, err := lbr.fetchFile(blockChunkPath)
+		if err != nil {
+			return fmt.Errorf("failed to fetch chunk file: %q: %w", chunkName, err)
+		}
+		if err := lbr.writeFile(temp, blockChunkPath, chunk); err != nil {
+			return fmt.Errorf("failed to write chunk file: %q: %s", chunkName, err)
+		}
+	}
+
+	// Set postingDecoder to nil because
+	// If it is nil then a default decoder is used, compatible with Prometheus v2.
+	pb, err := tsdb.OpenBlock(nil, temp, nil, nil)
+	if err != nil {
+		return fmt.Errorf("failed to open block %q: %w", lbr.ID, err)
+	}
+	lbr.reader = pb
+	return nil
+}
+
+// Index returns an IndexReader over the block's data.
+func (lbr *lazyBlockReader) Index() (tsdb.IndexReader, error) {
+	if err := lbr.initialize(); err != nil {
+		return nil, err
+	}
+	return lbr.reader.Index()
+}
+
+// Chunks returns a ChunkReader over the block's data.
+func (lbr *lazyBlockReader) Chunks() (tsdb.ChunkReader, error) {
+	if err := lbr.initialize(); err != nil {
+		return nil, err
+	}
+	return lbr.reader.Chunks()
+}
+
+// Tombstones returns a tombstones.Reader over the block's deleted data.
+func (lbr *lazyBlockReader) Tombstones() (tombstones.Reader, error) {
+	if err := lbr.initialize(); err != nil {
+		return nil, err
+	}
+	return lbr.reader.Tombstones()
+}
+
+// Meta provides meta information about the block reader.
+func (lbr *lazyBlockReader) Meta() tsdb.BlockMeta {
+	if err := lbr.initialize(); err != nil {
+		lbr.err = fmt.Errorf("cannot get BlockMeta: %w", err)
+		return tsdb.BlockMeta{}
+	}
+	return lbr.reader.Meta()
+}
+
+// Size returns the number of bytes that the block takes up on disk.
+func (lbr *lazyBlockReader) Size() int64 {
+	if err := lbr.initialize(); err != nil {
+		lbr.err = fmt.Errorf("error get Size of the block: %s, return zero size", err)
+		return 0
+	}
+	return lbr.reader.Size()
+}
+
+// Err returns the last error that occurred on the block reader.
+func (lbr *lazyBlockReader) Err() error {
+	return lbr.err
+}
+
+// Close closes block and releases all resources
+func (lbr *lazyBlockReader) Close() error {
+	lbr.mu.Lock()
+	defer lbr.mu.Unlock()
+	if lbr.reader == nil {
+		return nil
+	}
+
+	err := lbr.reader.Close()
+	if err := os.RemoveAll(lbr.tempDirPath); err != nil {
+		log.Printf("failed to remove temp dir: %s", err)
+	}
+	lbr.reader = nil
+	lbr.tempDirPath = ""
+
+	return err
+}
+
+func (lbr *lazyBlockReader) mkTempDir() (string, error) {
+	temp, err := os.MkdirTemp("", lbr.ID.String())
+	if err != nil {
+		return "", fmt.Errorf("failed to create temp dir: %s", err)
+	}
+	err = os.Mkdir(filepath.Join(temp, "chunks"), os.ModePerm)
+	if err != nil {
+		return "", fmt.Errorf("failed to create temp dir: %s", err)
+	}
+	return temp, nil
+}
+
+func (lbr *lazyBlockReader) fetchFile(filePath string) ([]byte, error) {
+	blockID := lbr.ID.String()
+	blockPath := filepath.Join(blockID, filePath)
+	has, err := lbr.fs.HasFile(blockPath)
+	if err != nil {
+		return nil, err
+	}
+	if !has {
+		return nil, fmt.Errorf("block meta %s not found", blockID)
+	}
+	return lbr.fs.ReadFile(blockPath)
+}
+
+func (lbr *lazyBlockReader) writeFile(folder string, filename string, file []byte) error {
+	fileName := filepath.Join(folder, filename)
+	return os.WriteFile(fileName, file, os.ModePerm)
+}

app/vmctl/mimir/mimir.go

@@ -0,0 +1,238 @@
+package mimir
+
+import (
+	"bytes"
+	"compress/gzip"
+	"context"
+	"encoding/json"
+	"fmt"
+	"log"
+
+	"github.com/oklog/ulid/v2"
+	"github.com/prometheus/prometheus/model/labels"
+	"github.com/prometheus/prometheus/tsdb"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/prometheus"
+	utils "github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/vmctlutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/backup/common"
+)
+
+const (
+	bucketIndex                   = "bucket-index.json"
+	bucketIndexCompressedFilename = bucketIndex + ".gz"
+	metaFilename                  = "meta.json"
+	indexFilename                 = "index"
+)
+
+// BlockDeletionMark holds the information about a block's deletion mark in the index.
+// This type was copied from the mimir repository https://github.com/grafana/mimir/blob/main/pkg/storage/tsdb/bucketindex/index.go#L234.
+type BlockDeletionMark struct {
+	// Block ID.
+	ID ulid.ULID `json:"block_id"`
+
+	// DeletionTime is a unix timestamp (seconds precision) of when the block was marked to be deleted.
+	DeletionTime int64 `json:"deletion_time"`
+}
+
+// Block holds the information about a block in the index.
+// This is a partial implementation of the https://github.com/grafana/mimir/blob/main/pkg/storage/tsdb/bucketindex/index.go#L73
+type Block struct {
+	// Block ID.
+	ID ulid.ULID `json:"block_id"`
+
+	// MinTime and MaxTime specify the time range all samples in the block are in (millis precision).
+	MinTime int64 `json:"min_time"`
+	MaxTime int64 `json:"max_time"`
+
+	// SegmentsFormat and SegmentsNum stores the format and number of chunks segments
+	// in the block.
+	SegmentsFormat string `json:"segments_format,omitempty"`
+	SegmentsNum    int    `json:"segments_num,omitempty"`
+}
+
+// Index contains all known blocks and markers of a tenant.
+// This is a partial implementation pof the https://github.com/grafana/mimir/blob/main/pkg/storage/tsdb/bucketindex/index.go#L36
+type Index struct {
+	// Version of the index format.
+	Version int `json:"version"`
+
+	// List of complete blocks (partial blocks are excluded from the index).
+	Blocks []*Block `json:"blocks"`
+}
+
+// Config contains a list of params needed
+// for reading mimir snapshots
+type Config struct {
+	// Path to remote storage bucket
+	Path string
+	// TenantID is the tenant id for the storage
+	TenantID string
+
+	Filter Filter
+
+	CredsFilePath           string
+	ConfigFilePath          string
+	ConfigProfile           string
+	CustomS3Endpoint        string
+	S3ForcePathStyle        bool
+	S3TLSInsecureSkipVerify bool
+
+	SSEKMSKeyID  string
+	SSEAlgorithm string
+}
+
+// Filter contains configuration for filtering
+// the timeseries
+type Filter struct {
+	TimeMin    string
+	TimeMax    string
+	Label      string
+	LabelValue string
+}
+
+// Client is a wrapper over Prometheus tsdb.DBReader
+type Client struct {
+	common.RemoteFS
+	filter filter
+}
+
+type filter struct {
+	min, max   int64
+	label      string
+	labelValue string
+}
+
+func (f filter) inRange(minTime, maxTime int64) bool {
+	fmin, fmax := f.min, f.max
+	if minTime == 0 {
+		fmin = minTime
+	}
+	if fmax == 0 {
+		fmax = maxTime
+	}
+	return minTime <= fmax && fmin <= maxTime
+}
+
+// NewClient creates and validates new Client
+// with given Config
+func NewClient(ctx context.Context, cfg Config) (*Client, error) {
+	if cfg.Path == "" {
+		return nil, fmt.Errorf("path cannot be empty")
+	}
+
+	if cfg.TenantID != "" {
+		cfg.Path = fmt.Sprintf("%s/%s", cfg.Path, cfg.TenantID)
+	}
+
+	var c Client
+	rfs, err := newRemoteFS(ctx, cfg)
+	if err != nil {
+		return nil, fmt.Errorf("cannot parse `-src`=%q: %w", cfg.Path, err)
+	}
+
+	c.RemoteFS = rfs
+	timeMin, err := utils.ParseTime(cfg.Filter.TimeMin)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse min time in filter: %s", err)
+	}
+	timeMax, err := utils.ParseTime(cfg.Filter.TimeMax)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse max time in filter: %s", err)
+	}
+	c.filter = filter{
+		min:        timeMin.UnixMilli(),
+		max:        timeMax.UnixMilli(),
+		label:      cfg.Filter.Label,
+		labelValue: cfg.Filter.LabelValue,
+	}
+	return &c, nil
+}
+
+// Explore a fetches bucket-index.json file from a remote storage or local filesystem
+// and filter blocks via the defined time range, but does not take into account label filters.
+func (c *Client) Explore() ([]tsdb.BlockReader, error) {
+
+	log.Printf("Fetching blocks from remote storage")
+
+	indexFile, err := c.fetchIndexFile()
+	if err != nil {
+		return nil, fmt.Errorf("failed to fetch index file: %s", err)
+	}
+
+	var blocksToImport []tsdb.BlockReader
+	for _, block := range indexFile.Blocks {
+		if !c.filter.inRange(block.MinTime, block.MaxTime) {
+			// Skipping block outside of time range
+			continue
+		}
+
+		if block.ID.String() == "" {
+			continue
+		}
+
+		lazyBlockReader, err := newLazyBlockReader(block, c.RemoteFS)
+		if err != nil {
+			return nil, fmt.Errorf("failed to create lazy block reader: %s", err)
+		}
+		blocksToImport = append(blocksToImport, lazyBlockReader)
+	}
+
+	return blocksToImport, nil
+}
+
+// Read reads the given BlockReader according to configured
+// time and label filters.
+func (c *Client) Read(ctx context.Context, block tsdb.BlockReader) (*prometheus.CloseableSeriesSet, error) {
+	meta := block.Meta()
+	if b, ok := block.(*lazyBlockReader); ok && b.Err() != nil {
+		return nil, fmt.Errorf("failed to read block: %s", b.Err())
+	}
+
+	if meta.ULID.String() == "" {
+		return nil, fmt.Errorf("unexpected block without id")
+	}
+
+	minTime, maxTime := meta.MinTime, meta.MaxTime
+	if c.filter.min != 0 {
+		minTime = c.filter.min
+	}
+	if c.filter.max != 0 {
+		maxTime = c.filter.max
+	}
+	q, err := tsdb.NewBlockQuerier(block, minTime, maxTime)
+	if err != nil {
+		return nil, err
+	}
+	ss := q.Select(ctx, false, nil, labels.MustNewMatcher(labels.MatchRegexp, c.filter.label, c.filter.labelValue))
+	return &prometheus.CloseableSeriesSet{SeriesSet: ss, Close: q.Close}, nil
+}
+
+func (c *Client) fetchIndexFile() (*Index, error) {
+	has, err := c.HasFile(bucketIndexCompressedFilename)
+	if err != nil {
+		return nil, err
+	}
+	if !has {
+		return nil, fmt.Errorf("bucket-index.json.gz not found")
+	}
+
+	file, err := c.ReadFile(bucketIndexCompressedFilename)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read bucket index: %s", err)
+	}
+
+	r := bytes.NewReader(file)
+	// Read all the content.
+	gzipReader, err := gzip.NewReader(r)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create gzip reader: %s", err)
+	}
+
+	var indexFile Index
+	err = json.NewDecoder(gzipReader).Decode(&indexFile)
+	if err != nil {
+		return nil, fmt.Errorf("failed to decode bucket index: %s", err)
+	}
+
+	return &indexFile, nil
+}

app/vmctl/mimir/remotefs.go

@@ -0,0 +1,93 @@
+package mimir
+
+import (
+	"context"
+	"fmt"
+	"path/filepath"
+	"strings"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/backup/azremote"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/backup/common"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/backup/fsremote"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/backup/gcsremote"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/backup/s3remote"
+)
+
+// newRemoteFS returns new remote fs from the given Config.
+func newRemoteFS(ctx context.Context, cfg Config) (common.RemoteFS, error) {
+	if len(cfg.Path) == 0 {
+		return nil, fmt.Errorf("path cannot be empty")
+	}
+	n := strings.Index(cfg.Path, "://")
+	if n < 0 {
+		return nil, fmt.Errorf("missing scheme in path %q. Supported schemes: `gs://`, `s3://`, `azblob://`, `fs://`", cfg.Path)
+	}
+	scheme := cfg.Path[:n]
+	dir := cfg.Path[n+len("://"):]
+	switch scheme {
+	case "fs":
+		if !filepath.IsAbs(dir) {
+			return nil, fmt.Errorf("dir must be absolute; got %q", dir)
+		}
+		fsr := &fsremote.FS{
+			Dir: filepath.Clean(dir),
+		}
+		return fsr, nil
+	case "gcs", "gs":
+		n := strings.Index(dir, "/")
+		if n < 0 {
+			return nil, fmt.Errorf("missing directory on the gcs bucket %q", dir)
+		}
+		bucket := dir[:n]
+		dir = dir[n:]
+		fsr := &gcsremote.FS{
+			CredsFilePath: cfg.CredsFilePath,
+			Bucket:        bucket,
+			Dir:           dir,
+		}
+		if err := fsr.Init(ctx); err != nil {
+			return nil, fmt.Errorf("cannot initialize connection to gcs: %w", err)
+		}
+		return fsr, nil
+	case "azblob":
+		n := strings.Index(dir, "/")
+		if n < 0 {
+			return nil, fmt.Errorf("missing directory on the AZBlob container %q", dir)
+		}
+		bucket := dir[:n]
+		dir = dir[n:]
+		fsr := &azremote.FS{
+			Container: bucket,
+			Dir:       dir,
+		}
+		if err := fsr.Init(ctx); err != nil {
+			return nil, fmt.Errorf("cannot initialize connection to AZBlob: %w", err)
+		}
+		return fsr, nil
+	case "s3":
+		n := strings.Index(dir, "/")
+		if n < 0 {
+			return nil, fmt.Errorf("missing directory on the s3 bucket %q", dir)
+		}
+		bucket := dir[:n]
+		dir = dir[n:]
+		fsr := &s3remote.FS{
+			CredsFilePath:         cfg.CredsFilePath,
+			ConfigFilePath:        cfg.ConfigFilePath,
+			CustomEndpoint:        cfg.CustomS3Endpoint,
+			TLSInsecureSkipVerify: cfg.S3TLSInsecureSkipVerify,
+			S3ForcePathStyle:      cfg.S3ForcePathStyle,
+			ProfileName:           cfg.ConfigProfile,
+			Bucket:                bucket,
+			Dir:                   dir,
+			SSEKMSKeyId:           cfg.SSEKMSKeyID,
+			SSEAlgorithm:          s3remote.StringToEncryptionAlgorithm(cfg.SSEAlgorithm),
+		}
+		if err := fsr.Init(ctx); err != nil {
+			return nil, fmt.Errorf("cannot initialize connection to s3: %w", err)
+		}
+		return fsr, nil
+	default:
+		return nil, fmt.Errorf("unsupported scheme %q", scheme)
+	}
+}

app/vmctl/prometheus.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"fmt"
+	"io"
 	"log"
 	"strings"
 	"sync"
@@ -18,10 +19,17 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/vm"
 )
 
+// Runner is an interface for fetching and reading
+// snapshot blocks
+type Runner interface {
+	Explore() ([]tsdb.BlockReader, error)
+	Read(context.Context, tsdb.BlockReader) (*prometheus.CloseableSeriesSet, error)
+}
+
 type prometheusProcessor struct {
-	// prometheus client fetches and reads
+	// Runner fetches and reads
 	// snapshot blocks
-	cl *prometheus.Client
+	cl Runner
 	// importer performs import requests
 	// for timeseries data returned from
 	// snapshot blocks
@@ -48,7 +56,7 @@ func (pp *prometheusProcessor) run(ctx context.Context) error {
 		return nil
 	}
 
-	if err := pp.processBlocks(blocks); err != nil {
+	if err := pp.processBlocks(ctx, blocks); err != nil {
 		return fmt.Errorf("migration failed: %s", err)
 	}
 
@@ -57,11 +65,17 @@ func (pp *prometheusProcessor) run(ctx context.Context) error {
 	return nil
 }
 
-func (pp *prometheusProcessor) do(b tsdb.BlockReader) error {
-	ss, err := pp.cl.Read(b)
+func (pp *prometheusProcessor) do(ctx context.Context, b tsdb.BlockReader) error {
+	css, err := pp.cl.Read(ctx, b)
 	if err != nil {
 		return fmt.Errorf("failed to read block: %s", err)
 	}
+	defer func() {
+		if err := css.Close(); err != nil {
+			log.Printf("cannot close SeriesSet for block: %q : %s\n", b.Meta().ULID, err)
+		}
+	}()
+	ss := css.SeriesSet
 	var it chunkenc.Iterator
 	for ss.Next() {
 		var name string
@@ -114,7 +128,7 @@ func (pp *prometheusProcessor) do(b tsdb.BlockReader) error {
 	return ss.Err()
 }
 
-func (pp *prometheusProcessor) processBlocks(blocks []tsdb.BlockReader) error {
+func (pp *prometheusProcessor) processBlocks(ctx context.Context, blocks []tsdb.BlockReader) error {
 	promBlocksTotal.Add(len(blocks))
 	bar := barpool.AddWithTemplate(fmt.Sprintf(barTpl, "Processing blocks"), len(blocks))
 	if err := barpool.Start(); err != nil {
@@ -130,11 +144,16 @@ func (pp *prometheusProcessor) processBlocks(blocks []tsdb.BlockReader) error {
 	for range pp.cc {
 		wg.Go(func() {
 			for br := range blockReadersCh {
-				if err := pp.do(br); err != nil {
+				if err := pp.do(ctx, br); err != nil {
 					promErrorsTotal.Inc()
-					errCh <- fmt.Errorf("read failed for block %q: %s", br.Meta().ULID, err)
+					errCh <- fmt.Errorf("cannot read block %q: %s", br.Meta().ULID, err)
 					return
 				}
+				if cb, ok := br.(io.Closer); ok {
+					if err := cb.Close(); err != nil {
+						errCh <- fmt.Errorf("cannot close block: %q: %w", br.Meta().ULID, err)
+					}
+				}
 				promBlocksProcessed.Inc()
 				bar.Increment()
 			}

app/vmctl/prometheus/prometheus.go

@@ -8,6 +8,8 @@ import (
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmctl/vmctlutil"
 )
 
 // Config contains a list of params needed
@@ -60,13 +62,13 @@ func NewClient(cfg Config) (*Client, error) {
 		return nil, fmt.Errorf("failed to open snapshot %q: %s", cfg.Snapshot, err)
 	}
 	c := &Client{DBReadOnly: db}
-	minTime, maxTime, err := parseTime(cfg.Filter.TimeMin, cfg.Filter.TimeMax)
+	timeMin, timeMax, err := parseTime(cfg.Filter.TimeMin, cfg.Filter.TimeMax)
 	if err != nil {
 		return nil, fmt.Errorf("failed to parse time in filter: %s", err)
 	}
 	c.filter = filter{
-		min:        minTime,
-		max:        maxTime,
+		min:        timeMin,
+		max:        timeMax,
 		label:      cfg.Filter.Label,
 		labelValue: cfg.Filter.LabelValue,
 	}
@@ -83,7 +85,7 @@ func (c *Client) Explore() ([]tsdb.BlockReader, error) {
 	if err != nil {
 		return nil, fmt.Errorf("failed to fetch blocks: %s", err)
 	}
-	s := &Stats{
+	s := &vmctlutil.Stats{
 		Filtered: c.filter.min != 0 || c.filter.max != 0 || c.filter.label != "",
 		Blocks:   len(blocks),
 	}
@@ -108,9 +110,15 @@ func (c *Client) Explore() ([]tsdb.BlockReader, error) {
 	return blocksToImport, nil
 }
 
+// CloseableSeriesSet defines a SeriesSet with Close method
+type CloseableSeriesSet struct {
+	SeriesSet storage.SeriesSet
+	Close     func() error
+}
+
 // Read reads the given BlockReader according to configured
 // time and label filters.
-func (c *Client) Read(block tsdb.BlockReader) (storage.SeriesSet, error) {
+func (c *Client) Read(ctx context.Context, block tsdb.BlockReader) (*CloseableSeriesSet, error) {
 	minTime, maxTime := block.Meta().MinTime, block.Meta().MaxTime
 	if c.filter.min != 0 {
 		minTime = c.filter.min
@@ -122,8 +130,8 @@ func (c *Client) Read(block tsdb.BlockReader) (storage.SeriesSet, error) {
 	if err != nil {
 		return nil, err
 	}
-	ss := q.Select(context.Background(), false, nil, labels.MustNewMatcher(labels.MatchRegexp, c.filter.label, c.filter.labelValue))
-	return ss, nil
+	ss := q.Select(ctx, false, nil, labels.MustNewMatcher(labels.MatchRegexp, c.filter.label, c.filter.labelValue))
+	return &CloseableSeriesSet{ss, q.Close}, nil
 }
 
 func parseTime(start, end string) (int64, int64, error) {

app/vmctl/vmctlutil/stats.go

@@ -1,4 +1,4 @@
-package prometheus
+package vmctlutil
 
 import (
 	"fmt"
@@ -18,7 +18,7 @@ type Stats struct {
 
 // String returns string representation for s.
 func (s Stats) String() string {
-	str := fmt.Sprintf("Prometheus snapshot stats:\n"+
+	str := fmt.Sprintf("Snapshot stats:\n"+
 		"  blocks found: %d;\n"+
 		"  blocks skipped by time filter: %d;\n"+
 		"  min time: %d (%v);\n"+

app/vmselect/clusternative/vmselect.go

@@ -36,6 +36,9 @@ var (
 func NewVMSelectServer(addr string) (*vmselectapi.Server, error) {
 	api := &vmstorageAPI{}
 	limits := vmselectapi.Limits{
+		MaxLabelNames:                 *maxTagKeys,
+		MaxLabelValues:                *maxTagValues,
+		MaxTagValueSuffixes:           *maxTagValueSuffixesPerSearch,
 		MaxConcurrentRequests:         *maxConcurrentRequests,
 		MaxConcurrentRequestsFlagName: "clusternative.maxConcurrentRequests",
 		MaxQueueDuration:              *maxQueueDuration,
@@ -66,9 +69,6 @@ func (api *vmstorageAPI) SearchMetricNames(qt *querytracer.Tracer, sq *storage.S
 }
 
 func (api *vmstorageAPI) LabelValues(qt *querytracer.Tracer, sq *storage.SearchQuery, labelName string, maxLabelValues int, deadline uint64) ([]string, error) {
-	if maxLabelValues <= 0 || maxLabelValues > *maxTagValues {
-		maxLabelValues = *maxTagValues
-	}
 	dl := searchutil.DeadlineFromTimestamp(deadline)
 	labelValues, _, err := netstorage.LabelValues(qt, true, labelName, sq, maxLabelValues, dl)
 	return labelValues, wrapClusterNativeError(err)
@@ -76,18 +76,12 @@ func (api *vmstorageAPI) LabelValues(qt *querytracer.Tracer, sq *storage.SearchQ
 
 func (api *vmstorageAPI) TagValueSuffixes(qt *querytracer.Tracer, accountID, projectID uint32, tr storage.TimeRange, tagKey, tagValuePrefix string, delimiter byte,
 	maxSuffixes int, deadline uint64) ([]string, error) {
-	if maxSuffixes <= 0 || maxSuffixes > *maxTagValueSuffixesPerSearch {
-		maxSuffixes = *maxTagValueSuffixesPerSearch
-	}
 	dl := searchutil.DeadlineFromTimestamp(deadline)
 	suffixes, _, err := netstorage.TagValueSuffixes(qt, accountID, projectID, true, tr, tagKey, tagValuePrefix, delimiter, maxSuffixes, dl)
 	return suffixes, wrapClusterNativeError(err)
 }
 
 func (api *vmstorageAPI) LabelNames(qt *querytracer.Tracer, sq *storage.SearchQuery, maxLabelNames int, deadline uint64) ([]string, error) {
-	if maxLabelNames <= 0 || maxLabelNames > *maxTagKeys {
-		maxLabelNames = *maxTagKeys
-	}
 	dl := searchutil.DeadlineFromTimestamp(deadline)
 	labelNames, _, err := netstorage.LabelNames(qt, true, sq, maxLabelNames, dl)
 	return labelNames, wrapClusterNativeError(err)

app/vmselect/netstorage/netstorage.go

@@ -2171,23 +2171,16 @@ func (snr *storageNodesRequest) collectResults(partialResultsCounter *metrics.Co
 		return false, nil
 	}
 
-	// Verify whether at least a single node per each group successfully returned result in order to be able returning partial result.
-	missingGroups := 0
 	var firstErr error
 	for g, errsPartial := range errsPartialPerGroup {
-		if len(errsPartial) == g.nodesCount {
-			missingGroups++
-			if firstErr == nil {
-				// Return only the first error, since it has no sense in returning all errors.
-				firstErr = errsPartial[0]
-			}
-		}
-		if len(errsPartial) > 0 {
-			partialErrorsLogger.Warnf("%d out of %d vmstorage nodes at group %q were unavailable during the query; a sample error: %s", len(errsPartial), len(sns), g.name, errsPartial[0])
+		if firstErr == nil {
+			// Return only the first error, since it has no sense in returning all errors.
+			firstErr = errsPartial[0]
 		}
+		partialErrorsLogger.Warnf("%d out of %d vmstorage nodes at group %q were unavailable during the query; a sample error: %s", len(errsPartial), g.nodesCount, g.name, errsPartial[0])
 	}
-	if missingGroups >= *globalReplicationFactor {
-		// Too many groups contain all the non-working vmstorage nodes.
+	if snr.denyPartialResponse || len(resultsCollectedPerGroup) == 0 {
+		// The response cannot be returned as partial.
 		// Returns 503 status code, so the caller could retry it if needed.
 		err := &httpserver.ErrorWithStatusCode{
 			Err:        firstErr,

app/vmselect/prometheus/federate.qtpl

@@ -2,13 +2,16 @@
 	"math"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/netstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+    "github.com/VictoriaMetrics/VictoriaMetrics/lib/promrelabel"
+    "github.com/VictoriaMetrics/VictoriaMetrics/lib/storage"
 ) %}
 
 {% stripspace %}
 
 // Federate writes rs in /federate format.
 // See https://prometheus.io/docs/prometheus/latest/federation/
-{% func Federate(rs *netstorage.Result) %}
+{% func Federate(rs *netstorage.Result, escapeScheme string) %}
 	{% code
 		values := rs.Values
 		timestamps := rs.Timestamps
@@ -24,10 +27,54 @@
 			See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3185
 		{% endcomment %}
 		{% return %}
-	{% endif %}
-	{%= prometheusMetricName(&rs.MetricName) %}{% space %}
+    {% endif %}
+
+    {% switch escapeScheme %}
+       {% case federateEscapeSchemeUTF8 %}
+          {%= prometheusFederateMetricNameUTF8(&rs.MetricName) %}{% space %}
+
+       {% case federateEscapeSchemeUnderscore %}
+         {%= prometheusFederateMetricNameEscapeUnderscore(&rs.MetricName) %}{% space %}
+
+       {% case "" %}
+         {%= prometheusMetricName(&rs.MetricName) %}{% space %}
+    {% endswitch %}
+
 	{%f= lastValue %}{% space %}
 	{%dl= timestamps[len(timestamps)-1] %}{% newline %}
 {% endfunc %}
 
+{% func prometheusFederateMetricNameEscapeUnderscore(mn *storage.MetricName) %}
+	{%s= promrelabel.SanitizeMetricName(bytesutil.ToUnsafeString(mn.MetricGroup)) %}
+	{% if len(mn.Tags) > 0 %}
+	{
+		{% code tags := mn.Tags %}
+		{%s= promrelabel.SanitizeLabelName(bytesutil.ToUnsafeString(tags[0].Key)) %}={%= escapePrometheusLabel(tags[0].Value) %}
+		{% code tags = tags[1:] %}
+		{% for i := range tags %}
+			{% code tag := &tags[i] %}
+			,{%s= promrelabel.SanitizeLabelName(bytesutil.ToUnsafeString(tag.Key)) %}={%= escapePrometheusLabel(tag.Value) %}
+		{% endfor %}
+	}
+	{% endif %}
+{% endfunc %}
+
+{% func prometheusFederateMetricNameUTF8(mn *storage.MetricName) %}
+	{
+        {%= escapePrometheusLabel(mn.MetricGroup) %}
+        {% if len(mn.Tags) > 0 %}
+        ,
+		{% code tags := mn.Tags %}
+		{%= escapePrometheusLabel(tags[0].Key) %}={%= escapePrometheusLabel(tags[0].Value) %}
+		{% code tags = tags[1:] %}
+		{% for i := range tags %}
+			{% code tag := &tags[i] %}
+			,{%= escapePrometheusLabel(tag.Key) %}={%= escapePrometheusLabel(tag.Value) %}
+		{% endfor %}
+        {% endif %}
+	}
+{% endfunc %}
+
+
+
 {% endstripspace %}

app/vmselect/prometheus/federate.qtpl.go

@@ -9,82 +9,241 @@ import (
 	"math"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/netstorage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promrelabel"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage"
 )
 
 // Federate writes rs in /federate format.// See https://prometheus.io/docs/prometheus/latest/federation/
 
-//line app/vmselect/prometheus/federate.qtpl:11
+//line app/vmselect/prometheus/federate.qtpl:14
 import (
 	qtio422016 "io"
 
 	qt422016 "github.com/valyala/quicktemplate"
 )
 
-//line app/vmselect/prometheus/federate.qtpl:11
+//line app/vmselect/prometheus/federate.qtpl:14
 var (
 	_ = qtio422016.Copy
 	_ = qt422016.AcquireByteBuffer
 )
 
-//line app/vmselect/prometheus/federate.qtpl:11
-func StreamFederate(qw422016 *qt422016.Writer, rs *netstorage.Result) {
-//line app/vmselect/prometheus/federate.qtpl:13
+//line app/vmselect/prometheus/federate.qtpl:14
+func StreamFederate(qw422016 *qt422016.Writer, rs *netstorage.Result, escapeScheme string) {
+//line app/vmselect/prometheus/federate.qtpl:16
 	values := rs.Values
 	timestamps := rs.Timestamps
 
-//line app/vmselect/prometheus/federate.qtpl:16
+//line app/vmselect/prometheus/federate.qtpl:19
 	if len(timestamps) == 0 || len(values) == 0 {
-//line app/vmselect/prometheus/federate.qtpl:16
+//line app/vmselect/prometheus/federate.qtpl:19
 		return
-//line app/vmselect/prometheus/federate.qtpl:16
+//line app/vmselect/prometheus/federate.qtpl:19
 	}
-//line app/vmselect/prometheus/federate.qtpl:18
+//line app/vmselect/prometheus/federate.qtpl:21
 	lastValue := values[len(values)-1]
 
-//line app/vmselect/prometheus/federate.qtpl:20
+//line app/vmselect/prometheus/federate.qtpl:23
 	if math.IsNaN(lastValue) {
-//line app/vmselect/prometheus/federate.qtpl:26
+//line app/vmselect/prometheus/federate.qtpl:29
 		return
-//line app/vmselect/prometheus/federate.qtpl:27
+//line app/vmselect/prometheus/federate.qtpl:30
 	}
-//line app/vmselect/prometheus/federate.qtpl:28
-	streamprometheusMetricName(qw422016, &rs.MetricName)
-//line app/vmselect/prometheus/federate.qtpl:28
-	qw422016.N().S(` `)
-//line app/vmselect/prometheus/federate.qtpl:29
+//line app/vmselect/prometheus/federate.qtpl:32
+	switch escapeScheme {
+//line app/vmselect/prometheus/federate.qtpl:33
+	case federateEscapeSchemeUTF8:
+//line app/vmselect/prometheus/federate.qtpl:34
+		streamprometheusFederateMetricNameUTF8(qw422016, &rs.MetricName)
+//line app/vmselect/prometheus/federate.qtpl:34
+		qw422016.N().S(` `)
+//line app/vmselect/prometheus/federate.qtpl:36
+	case federateEscapeSchemeUnderscore:
+//line app/vmselect/prometheus/federate.qtpl:37
+		streamprometheusFederateMetricNameEscapeUnderscore(qw422016, &rs.MetricName)
+//line app/vmselect/prometheus/federate.qtpl:37
+		qw422016.N().S(` `)
+//line app/vmselect/prometheus/federate.qtpl:39
+	case "":
+//line app/vmselect/prometheus/federate.qtpl:40
+		streamprometheusMetricName(qw422016, &rs.MetricName)
+//line app/vmselect/prometheus/federate.qtpl:40
+		qw422016.N().S(` `)
+//line app/vmselect/prometheus/federate.qtpl:41
+	}
+//line app/vmselect/prometheus/federate.qtpl:43
 	qw422016.N().F(lastValue)
-//line app/vmselect/prometheus/federate.qtpl:29
+//line app/vmselect/prometheus/federate.qtpl:43
 	qw422016.N().S(` `)
-//line app/vmselect/prometheus/federate.qtpl:30
+//line app/vmselect/prometheus/federate.qtpl:44
 	qw422016.N().DL(timestamps[len(timestamps)-1])
-//line app/vmselect/prometheus/federate.qtpl:30
+//line app/vmselect/prometheus/federate.qtpl:44
 	qw422016.N().S(`
 `)
-//line app/vmselect/prometheus/federate.qtpl:31
+//line app/vmselect/prometheus/federate.qtpl:45
 }
 
-//line app/vmselect/prometheus/federate.qtpl:31
-func WriteFederate(qq422016 qtio422016.Writer, rs *netstorage.Result) {
-//line app/vmselect/prometheus/federate.qtpl:31
+//line app/vmselect/prometheus/federate.qtpl:45
+func WriteFederate(qq422016 qtio422016.Writer, rs *netstorage.Result, escapeScheme string) {
+//line app/vmselect/prometheus/federate.qtpl:45
 	qw422016 := qt422016.AcquireWriter(qq422016)
-//line app/vmselect/prometheus/federate.qtpl:31
-	StreamFederate(qw422016, rs)
-//line app/vmselect/prometheus/federate.qtpl:31
+//line app/vmselect/prometheus/federate.qtpl:45
+	StreamFederate(qw422016, rs, escapeScheme)
+//line app/vmselect/prometheus/federate.qtpl:45
 	qt422016.ReleaseWriter(qw422016)
-//line app/vmselect/prometheus/federate.qtpl:31
+//line app/vmselect/prometheus/federate.qtpl:45
 }
 
-//line app/vmselect/prometheus/federate.qtpl:31
-func Federate(rs *netstorage.Result) string {
-//line app/vmselect/prometheus/federate.qtpl:31
+//line app/vmselect/prometheus/federate.qtpl:45
+func Federate(rs *netstorage.Result, escapeScheme string) string {
+//line app/vmselect/prometheus/federate.qtpl:45
 	qb422016 := qt422016.AcquireByteBuffer()
-//line app/vmselect/prometheus/federate.qtpl:31
-	WriteFederate(qb422016, rs)
-//line app/vmselect/prometheus/federate.qtpl:31
+//line app/vmselect/prometheus/federate.qtpl:45
+	WriteFederate(qb422016, rs, escapeScheme)
+//line app/vmselect/prometheus/federate.qtpl:45
 	qs422016 := string(qb422016.B)
-//line app/vmselect/prometheus/federate.qtpl:31
+//line app/vmselect/prometheus/federate.qtpl:45
 	qt422016.ReleaseByteBuffer(qb422016)
-//line app/vmselect/prometheus/federate.qtpl:31
+//line app/vmselect/prometheus/federate.qtpl:45
 	return qs422016
-//line app/vmselect/prometheus/federate.qtpl:31
+//line app/vmselect/prometheus/federate.qtpl:45
+}
+
+//line app/vmselect/prometheus/federate.qtpl:47
+func streamprometheusFederateMetricNameEscapeUnderscore(qw422016 *qt422016.Writer, mn *storage.MetricName) {
+//line app/vmselect/prometheus/federate.qtpl:48
+	qw422016.N().S(promrelabel.SanitizeMetricName(bytesutil.ToUnsafeString(mn.MetricGroup)))
+//line app/vmselect/prometheus/federate.qtpl:49
+	if len(mn.Tags) > 0 {
+//line app/vmselect/prometheus/federate.qtpl:49
+		qw422016.N().S(`{`)
+//line app/vmselect/prometheus/federate.qtpl:51
+		tags := mn.Tags
+
+//line app/vmselect/prometheus/federate.qtpl:52
+		qw422016.N().S(promrelabel.SanitizeLabelName(bytesutil.ToUnsafeString(tags[0].Key)))
+//line app/vmselect/prometheus/federate.qtpl:52
+		qw422016.N().S(`=`)
+//line app/vmselect/prometheus/federate.qtpl:52
+		streamescapePrometheusLabel(qw422016, tags[0].Value)
+//line app/vmselect/prometheus/federate.qtpl:53
+		tags = tags[1:]
+
+//line app/vmselect/prometheus/federate.qtpl:54
+		for i := range tags {
+//line app/vmselect/prometheus/federate.qtpl:55
+			tag := &tags[i]
+
+//line app/vmselect/prometheus/federate.qtpl:55
+			qw422016.N().S(`,`)
+//line app/vmselect/prometheus/federate.qtpl:56
+			qw422016.N().S(promrelabel.SanitizeLabelName(bytesutil.ToUnsafeString(tag.Key)))
+//line app/vmselect/prometheus/federate.qtpl:56
+			qw422016.N().S(`=`)
+//line app/vmselect/prometheus/federate.qtpl:56
+			streamescapePrometheusLabel(qw422016, tag.Value)
+//line app/vmselect/prometheus/federate.qtpl:57
+		}
+//line app/vmselect/prometheus/federate.qtpl:57
+		qw422016.N().S(`}`)
+//line app/vmselect/prometheus/federate.qtpl:59
+	}
+//line app/vmselect/prometheus/federate.qtpl:60
+}
+
+//line app/vmselect/prometheus/federate.qtpl:60
+func writeprometheusFederateMetricNameEscapeUnderscore(qq422016 qtio422016.Writer, mn *storage.MetricName) {
+//line app/vmselect/prometheus/federate.qtpl:60
+	qw422016 := qt422016.AcquireWriter(qq422016)
+//line app/vmselect/prometheus/federate.qtpl:60
+	streamprometheusFederateMetricNameEscapeUnderscore(qw422016, mn)
+//line app/vmselect/prometheus/federate.qtpl:60
+	qt422016.ReleaseWriter(qw422016)
+//line app/vmselect/prometheus/federate.qtpl:60
+}
+
+//line app/vmselect/prometheus/federate.qtpl:60
+func prometheusFederateMetricNameEscapeUnderscore(mn *storage.MetricName) string {
+//line app/vmselect/prometheus/federate.qtpl:60
+	qb422016 := qt422016.AcquireByteBuffer()
+//line app/vmselect/prometheus/federate.qtpl:60
+	writeprometheusFederateMetricNameEscapeUnderscore(qb422016, mn)
+//line app/vmselect/prometheus/federate.qtpl:60
+	qs422016 := string(qb422016.B)
+//line app/vmselect/prometheus/federate.qtpl:60
+	qt422016.ReleaseByteBuffer(qb422016)
+//line app/vmselect/prometheus/federate.qtpl:60
+	return qs422016
+//line app/vmselect/prometheus/federate.qtpl:60
+}
+
+//line app/vmselect/prometheus/federate.qtpl:62
+func streamprometheusFederateMetricNameUTF8(qw422016 *qt422016.Writer, mn *storage.MetricName) {
+//line app/vmselect/prometheus/federate.qtpl:62
+	qw422016.N().S(`{`)
+//line app/vmselect/prometheus/federate.qtpl:64
+	streamescapePrometheusLabel(qw422016, mn.MetricGroup)
+//line app/vmselect/prometheus/federate.qtpl:65
+	if len(mn.Tags) > 0 {
+//line app/vmselect/prometheus/federate.qtpl:65
+		qw422016.N().S(`,`)
+//line app/vmselect/prometheus/federate.qtpl:67
+		tags := mn.Tags
+
+//line app/vmselect/prometheus/federate.qtpl:68
+		streamescapePrometheusLabel(qw422016, tags[0].Key)
+//line app/vmselect/prometheus/federate.qtpl:68
+		qw422016.N().S(`=`)
+//line app/vmselect/prometheus/federate.qtpl:68
+		streamescapePrometheusLabel(qw422016, tags[0].Value)
+//line app/vmselect/prometheus/federate.qtpl:69
+		tags = tags[1:]
+
+//line app/vmselect/prometheus/federate.qtpl:70
+		for i := range tags {
+//line app/vmselect/prometheus/federate.qtpl:71
+			tag := &tags[i]
+
+//line app/vmselect/prometheus/federate.qtpl:71
+			qw422016.N().S(`,`)
+//line app/vmselect/prometheus/federate.qtpl:72
+			streamescapePrometheusLabel(qw422016, tag.Key)
+//line app/vmselect/prometheus/federate.qtpl:72
+			qw422016.N().S(`=`)
+//line app/vmselect/prometheus/federate.qtpl:72
+			streamescapePrometheusLabel(qw422016, tag.Value)
+//line app/vmselect/prometheus/federate.qtpl:73
+		}
+//line app/vmselect/prometheus/federate.qtpl:74
+	}
+//line app/vmselect/prometheus/federate.qtpl:74
+	qw422016.N().S(`}`)
+//line app/vmselect/prometheus/federate.qtpl:76
+}
+
+//line app/vmselect/prometheus/federate.qtpl:76
+func writeprometheusFederateMetricNameUTF8(qq422016 qtio422016.Writer, mn *storage.MetricName) {
+//line app/vmselect/prometheus/federate.qtpl:76
+	qw422016 := qt422016.AcquireWriter(qq422016)
+//line app/vmselect/prometheus/federate.qtpl:76
+	streamprometheusFederateMetricNameUTF8(qw422016, mn)
+//line app/vmselect/prometheus/federate.qtpl:76
+	qt422016.ReleaseWriter(qw422016)
+//line app/vmselect/prometheus/federate.qtpl:76
+}
+
+//line app/vmselect/prometheus/federate.qtpl:76
+func prometheusFederateMetricNameUTF8(mn *storage.MetricName) string {
+//line app/vmselect/prometheus/federate.qtpl:76
+	qb422016 := qt422016.AcquireByteBuffer()
+//line app/vmselect/prometheus/federate.qtpl:76
+	writeprometheusFederateMetricNameUTF8(qb422016, mn)
+//line app/vmselect/prometheus/federate.qtpl:76
+	qs422016 := string(qb422016.B)
+//line app/vmselect/prometheus/federate.qtpl:76
+	qt422016.ReleaseByteBuffer(qb422016)
+//line app/vmselect/prometheus/federate.qtpl:76
+	return qs422016
+//line app/vmselect/prometheus/federate.qtpl:76
 }

app/vmselect/prometheus/federate_test.go

@@ -8,15 +8,15 @@ import (
 )
 
 func TestFederate(t *testing.T) {
-	f := func(rs *netstorage.Result, expectedResult string) {
+	f := func(rs *netstorage.Result, escapeScheme string, expectedResult string) {
 		t.Helper()
-		result := Federate(rs)
+		result := Federate(rs, escapeScheme)
 		if result != expectedResult {
 			t.Fatalf("unexpected result; got\n%s\nwant\n%s", result, expectedResult)
 		}
 	}
 
-	f(&netstorage.Result{}, ``)
+	f(&netstorage.Result{}, ``, ``)
 
 	f(&netstorage.Result{
 		MetricName: storage.MetricName{
@@ -39,5 +39,60 @@ func TestFederate(t *testing.T) {
 		},
 		Values:     []float64{1.23},
 		Timestamps: []int64{123},
-	}, `foo{a="b",qqq="\\",abc="a<b\"\\c"} 1.23 123`+"\n")
+	}, ``, `foo{a="b",qqq="\\",abc="a<b\"\\c"} 1.23 123`+"\n")
+
+	f(&netstorage.Result{
+		MetricName: storage.MetricName{
+			MetricGroup: []byte("foo.bar"),
+			Tags: []storage.Tag{
+				{
+					Key:   []byte("some.!other"),
+					Value: []byte("value.unchanged!."),
+				},
+				{
+					Key:   []byte("qqq"),
+					Value: []byte("\\"),
+				},
+				{
+					Key:   []byte("!key"),
+					Value: []byte("value"),
+				},
+				{
+					Key: []byte("abc"),
+					// Verify that < isn't encoded. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5431
+					Value: []byte("a<b\"\\c"),
+				},
+			},
+		},
+		Values:     []float64{1.23},
+		Timestamps: []int64{123},
+	}, federateEscapeSchemeUnderscore, `foo_bar{some__other="value.unchanged!.",qqq="\\",_key="value",abc="a<b\"\\c"} 1.23 123`+"\n")
+
+	f(&netstorage.Result{
+		MetricName: storage.MetricName{
+			MetricGroup: []byte("foo.bar"),
+			Tags: []storage.Tag{
+				{
+					Key:   []byte("some.!other"),
+					Value: []byte("value.unchanged!."),
+				},
+				{
+					Key:   []byte("qqq"),
+					Value: []byte("\\"),
+				},
+				{
+					Key:   []byte("!key"),
+					Value: []byte("value"),
+				},
+				{
+					Key: []byte(`ab"c`),
+					// Verify that < isn't encoded. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5431
+					Value: []byte("a<b\"\\c"),
+				},
+			},
+		},
+		Values:     []float64{1.23},
+		Timestamps: []int64{123},
+	}, federateEscapeSchemeUTF8, `{"foo.bar","some.!other"="value.unchanged!.","qqq"="\\","!key"="value","ab\"c"="a<b\"\\c"} 1.23 123`+"\n")
+
 }

app/vmselect/prometheus/federate_timing_test.go

@@ -9,16 +9,17 @@ import (
 )
 
 func BenchmarkFederate(b *testing.B) {
+
 	rs := &netstorage.Result{
 		MetricName: storage.MetricName{
-			MetricGroup: []byte("foo_bar_bazaaaa_total"),
+			MetricGroup: []byte("foo_bar_?_._bazaaaa_total"),
 			Tags: []storage.Tag{
 				{
-					Key:   []byte("instance"),
+					Key:   []byte("instance:job"),
 					Value: []byte("foobarbaz:2344"),
 				},
 				{
-					Key:   []byte("job"),
+					Key:   []byte("job.name"),
 					Value: []byte("aaabbbccc"),
 				},
 			},
@@ -27,12 +28,22 @@ func BenchmarkFederate(b *testing.B) {
 		Timestamps: []int64{1234567890},
 	}
 
-	b.ReportAllocs()
-	b.RunParallel(func(pb *testing.PB) {
-		var bb bytes.Buffer
-		for pb.Next() {
-			bb.Reset()
-			WriteFederate(&bb, rs)
-		}
-	})
+	f := func(name, escapeScheme string) {
+		b.Helper()
+
+		b.Run(name, func(b *testing.B) {
+			b.ReportAllocs()
+			b.RunParallel(func(pb *testing.PB) {
+				var bb bytes.Buffer
+				for pb.Next() {
+					bb.Reset()
+					WriteFederate(&bb, rs, escapeScheme)
+				}
+			})
+		})
+	}
+
+	f("without escape", "")
+	f("allow-utf-8", federateEscapeSchemeUTF8)
+	f("legacy-underscore", federateEscapeSchemeUnderscore)
 }

app/vmselect/prometheus/prometheus.go

@@ -112,6 +112,11 @@ func PrettifyQuery(w http.ResponseWriter, r *http.Request) {
 	_ = bw.Flush()
 }
 
+const (
+	federateEscapeSchemeUnderscore = "underscore"
+	federateEscapeSchemeUTF8       = "utf-8"
+)
+
 // FederateHandler implements /federate . See https://prometheus.io/docs/prometheus/latest/federation/
 func FederateHandler(startTime time.Time, at *auth.Token, w http.ResponseWriter, r *http.Request) error {
 	defer federateDuration.UpdateDuration(startTime)
@@ -144,6 +149,21 @@ func FederateHandler(startTime time.Time, at *auth.Token, w http.ResponseWriter,
 		return fmt.Errorf("cannot export federated metrics, because some of vmstorage nodes are unavailable")
 	}
 
+	// add best-effort format negotiation
+	// modern version of Prometheus always set allow-utf-8 in order to properly parse utf-8 names and labels
+	// prometheus below v3 uses underscore escaping by default and it's the most common standard
+	var escapeScheme string
+	accept := r.Header.Get("Accept")
+	if len(accept) > 0 && strings.Contains(accept, "allow-utf-8") {
+		escapeScheme = federateEscapeSchemeUTF8
+	}
+	// try fallback to legacy underscore escaping if needed for Prometheus only,
+	// it's not widely used after Prometheus v3.0 release
+	// most of the Prometheus scrapers already use allow-utf-8 header
+	isPrometheus := strings.HasPrefix(r.UserAgent(), "Prometheus")
+	if len(escapeScheme) == 0 && isPrometheus {
+		escapeScheme = federateEscapeSchemeUnderscore
+	}
 	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
 	bw := bufferedwriter.Get(w)
 	defer bufferedwriter.Put(bw)
@@ -153,7 +173,7 @@ func FederateHandler(startTime time.Time, at *auth.Token, w http.ResponseWriter,
 			return err
 		}
 		bb := sw.getBuffer(workerID)
-		WriteFederate(bb, rs)
+		WriteFederate(bb, rs, escapeScheme)
 		return sw.maybeFlushBuffer(bb)
 	})
 	if err == nil {

app/vmselect/promql/rollup.go

@@ -2444,8 +2444,15 @@ func rollupIntegrate(rfa *rollupFuncArg) float64 {
 		prevTimestamp = timestamp
 		prevValue = v
 	}
-	dt := float64(rfa.currTimestamp-prevTimestamp) / 1e3
-	sum += prevValue * dt
+	// Only extrapolate the last value through to currTimestamp when the time
+	// series has any sample after the lookbehind window. When realNextValue is
+	// NaN the series has effectively ended at prevTimestamp, so accruing area
+	// past it would overcount the integral.
+	// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/9474
+	if !math.IsNaN(rfa.realNextValue) {
+		dt := float64(rfa.currTimestamp-prevTimestamp) / 1e3
+		sum += prevValue * dt
+	}
 	return sum
 }
 

app/vmselect/promql/rollup_test.go

@@ -1385,10 +1385,65 @@ func TestRollupFuncsNoWindow(t *testing.T) {
 		if samplesScanned != 24 {
 			t.Fatalf("expecting 24 samplesScanned from rollupConfig.Do; got %d", samplesScanned)
 		}
-		valuesExpected := []float64{nan, 2.148, 1.593, 1.156, 1.36}
+		// At tEnd=160 the series has no samples past the window (last sample is at
+		// ts=130), so integrate() must not extrapolate prevValue through tEnd.
+		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/9474
+		valuesExpected := []float64{nan, 2.148, 1.593, 1.156, 0.34}
 		timestampsExpected := []int64{0, 40, 80, 120, 160}
 		testRowsEqual(t, values, rc.Timestamps, valuesExpected, timestampsExpected)
 	})
+	t.Run("integrate_past_series_end", func(t *testing.T) {
+		// Constant series of value 1.0 from t=0..3600s (1h) at 60s step.
+		// Query integrate(metric[1h]) across t=0..10800s with 600s step.
+		// For t=0..3600s the window overlap with the data is [0,t], so the integral grows from 0 to 3600 (seconds).
+		// After the series ends, integrate must NOT keep accruing 3600 — it
+		// should taper to 0 once the lookbehind window is entirely past the
+		// last sample.
+		// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/9474
+		var testValues []int64
+		var testTimestamps []float64
+		for t := int64(0); t <= 3600_000; t += 60_000 {
+			testValues = append(testValues, t)
+			testTimestamps = append(testTimestamps, 1.0)
+		}
+		rc := rollupConfig{
+			Func:               rollupIntegrate,
+			Start:              0,
+			End:                10800_000,
+			Step:               600_000,
+			Window:             3600_000,
+			MaxPointsPerSeries: 1e4,
+		}
+		rc.Timestamps = rc.getTimestamps()
+		values, _ := rc.Do(nil, testTimestamps, testValues)
+		for i, ti := range rc.Timestamps {
+			v := values[i]
+
+			// For t<=3600s: window overlap is [0,ti], integral equals ti in seconds.
+			if ti <= 3600_000 {
+				expV := float64(ti / 1e3)
+				if v != expV {
+					t.Fatalf("unexpected integrate result at t=%ds, want=%.3f got=%.3f", ti/1e3, expV, v)
+				}
+				continue
+			}
+			// For 3600s<t<7200s: data is partially outside the window, so the
+			// integral shrinks linearly from 3600 to 0 as t approaches 7200s.
+			if ti > 3600_000 && ti < 7200_000 {
+				expV := float64((7200_000 - ti) / 1e3)
+				if v != expV {
+					t.Fatalf("unexpected integrate result at t=%ds, want=%.3f got=%.3f", ti/1e3, expV, v)
+				}
+				continue
+			}
+			if ti >= 7200_000 {
+				// Window entirely past data end: must be NaN.
+				if !math.IsNaN(v) {
+					t.Fatalf("unexpected integrate result at t=%ds, want=NaN got=%.3f", ti/1e3, v)
+				}
+			}
+		}
+	})
 	t.Run("distinct_over_time_1", func(t *testing.T) {
 		rc := rollupConfig{
 			Func:               rollupDistinct,

app/vmselect/vmui/index.html

@@ -37,7 +37,7 @@
   <meta property="og:title" content="UI for VictoriaMetrics">
   <meta property="og:url" content="https://victoriametrics.com/">
   <meta property="og:description" content="Explore and troubleshoot your VictoriaMetrics data">
-  <script type="module" crossorigin src="./assets/index-BjJ7fDL7.js"></script>
+  <script type="module" crossorigin src="./assets/index-U3iNn2Tx.js"></script>
   <link rel="modulepreload" crossorigin href="./assets/rolldown-runtime-COnpUsM8.js">
   <link rel="modulepreload" crossorigin href="./assets/vendor-C8Kwp93_.js">
   <link rel="stylesheet" crossorigin href="./assets/vendor-CnsZ1jie.css">

app/vmstorage/main.go

@@ -9,10 +9,12 @@ import (
 	"os"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/VictoriaMetrics/metrics"
 
+	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmstorage/servers"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/buildinfo"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/envflag"
@@ -27,8 +29,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/pushmetrics"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/stringsutil"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/vminsertapi"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/vmselectapi"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/timeutil"
 )
 
 var (
@@ -41,23 +42,12 @@ var (
 	useProxyProtocol = flagutil.NewArrayBool("httpListenAddr.useProxyProtocol", "Whether to use proxy protocol for connections accepted at the given -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")
-	vminsertAddr          = flag.String("vminsertAddr", ":8400", "TCP address to accept connections from vminsert services")
-	vmselectAddr          = flag.String("vmselectAddr", ":8401", "TCP address to accept connections from vmselect services")
-	maxConcurrentRequests = flag.Int("search.maxConcurrentRequests", 2*cgroup.AvailableCPUs(), "The maximum number of concurrent vmselect requests "+
-		"the vmstorage can process at -vmselectAddr. It shouldn't be high, since a single request usually saturates a CPU core, and 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 incoming vmselect request waits for execution "+
-		"when -search.maxConcurrentRequests limit is reached")
-	disableRPCCompression = flag.Bool("rpc.disableCompression", false, "Whether to disable compression of the data sent from vmstorage to vmselect. "+
-		"This reduces CPU usage at the cost of higher network bandwidth usage")
-	vminsertConnsShutdownDuration = flag.Duration("storage.vminsertConnsShutdownDuration", 10*time.Second, "The time needed for gradual closing of vminsert connections during "+
-		"graceful shutdown. Bigger duration reduces spikes in CPU, RAM and disk IO load on the remaining vmstorage nodes during rolling restart. "+
-		"Smaller duration reduces the time needed to close all the vminsert connections, thus reducing the time for graceful shutdown. "+
-		"Configured value must always be lower than the graceful shutdown period configured by the orchestration platform (terminationGracePeriodSeconds for Kubernetes). "+
-		"See https://docs.victoriametrics.com/victoriametrics/cluster-victoriametrics/#improving-re-routing-performance-during-restart")
+	vminsertAddr      = flag.String("vminsertAddr", ":8400", "TCP address to accept connections from vminsert services")
+	vmselectAddr      = flag.String("vmselectAddr", ":8401", "TCP address to accept connections from vmselect services")
 	snapshotAuthKey   = flagutil.NewPassword("snapshotAuthKey", "authKey, which must be passed in query string to /snapshot* pages. It overrides -httpAuth.*")
 	forceMergeAuthKey = flagutil.NewPassword("forceMergeAuthKey", "authKey, which must be passed in query string to /internal/force_merge pages. It overrides -httpAuth.*")
 	forceFlushAuthKey = flagutil.NewPassword("forceFlushAuthKey", "authKey, which must be passed in query string to /internal/force_flush pages. It overrides -httpAuth.*")
+	snapshotsMaxAge   = flagutil.NewRetentionDuration("snapshotsMaxAge", "3d", "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")
 	_                 = flag.Duration("snapshotCreateTimeout", 0, "Deprecated: this flag does nothing")
 
 	_ = flag.Duration("finalMergeDelay", 0, "Deprecated: this flag does nothing")
@@ -129,7 +119,7 @@ var (
 )
 
 func main() {
-	// vmstorage is optimized for reduced memory allocations,
+	// vmstoage is optimized for reduced memory allocations,
 	// so it can run with the reduced GOGC in order to reduce the used memory,
 	// while keeping CPU usage spent in GC at low levels.
 	//
@@ -188,7 +178,7 @@ func main() {
 		LogNewSeries:                *logNewSeries,
 	}
 	strg := storage.MustOpenStorage(*storageDataPath, opts)
-	vmStorage := newVMStorage(strg, *maxConcurrentRequests)
+	initStaleSnapshotsRemover(strg)
 
 	var m storage.Metrics
 	strg.UpdateMetrics(&m)
@@ -203,24 +193,18 @@ func main() {
 	// register storage metrics
 	storageMetrics := metrics.NewSet()
 	storageMetrics.RegisterMetricsWriter(func(w io.Writer) {
-		vmStorage.writeStorageMetrics(w)
+		writeStorageMetrics(w, strg)
 	})
 	metrics.RegisterSet(storageMetrics)
 
 	protoparserutil.StartUnmarshalWorkers()
 
-	vminsertSrv, err := vminsertapi.NewVMInsertServer(*vminsertAddr, *vminsertConnsShutdownDuration, "vminsert", vmStorage, nil)
+	servers.GetMaxUniqueTimeSeries() // for init and logging only.
+	vminsertSrv, err := servers.NewVMInsertServer(*vminsertAddr, strg)
 	if err != nil {
 		logger.Fatalf("cannot create a server with -vminsertAddr=%s: %s", *vminsertAddr, err)
-
 	}
-	limits := vmselectapi.Limits{
-		MaxConcurrentRequests:         *maxConcurrentRequests,
-		MaxConcurrentRequestsFlagName: "search.maxConcurrentRequests",
-		MaxQueueDuration:              *maxQueueDuration,
-		MaxQueueDurationFlagName:      "search.maxQueueDuration",
-	}
-	vmselectSrv, err := vmselectapi.NewServer(*vmselectAddr, vmStorage, limits, *disableRPCCompression)
+	vmselectSrv, err := servers.NewVMSelectServer(*vmselectAddr, strg)
 	if err != nil {
 		logger.Fatalf("cannot create a server with -vmselectAddr=%s: %s", *vmselectAddr, err)
 	}
@@ -229,7 +213,8 @@ func main() {
 	if len(listenAddrs) == 0 {
 		listenAddrs = []string{":8482"}
 	}
-	go httpserver.Serve(listenAddrs, vmStorage.requestHandler, httpserver.ServeOptions{UseProxyProtocol: useProxyProtocol})
+	requestHandler := newRequestHandler(strg)
+	go httpserver.Serve(listenAddrs, requestHandler, httpserver.ServeOptions{UseProxyProtocol: useProxyProtocol})
 
 	pushmetrics.Init()
 	sig := procutil.WaitForSigterm()
@@ -249,6 +234,7 @@ func main() {
 	metrics.UnregisterSet(storageMetrics, true)
 	storageMetrics = nil
 
+	stopStaleSnapshotsRemover()
 	vmselectSrv.MustStop()
 	vminsertSrv.MustStop()
 	protoparserutil.StopUnmarshalWorkers()
@@ -256,29 +242,31 @@ func main() {
 
 	logger.Infof("gracefully closing the storage at %s", *storageDataPath)
 	startTime = time.Now()
-	vmStorage.Stop()
+	strg.MustClose()
 	logger.Infof("successfully closed the storage in %.3f seconds", time.Since(startTime).Seconds())
 
 	fs.MustStopDirRemover()
 	logger.Infof("the vmstorage has been stopped")
 }
 
-// requestHandler is a storage request handler.
-// TODO(@rtm0): Move to a separate file, request_handler.go
-func (api *VMStorage) requestHandler(w http.ResponseWriter, r *http.Request) bool {
-	path := r.URL.Path
-
-	if path == "/" {
-		if r.Method != http.MethodGet {
-			return false
-		}
-		w.Header().Add("Content-Type", "text/html; charset=utf-8")
-		fmt.Fprintf(w, `vmstorage - a component of VictoriaMetrics cluster<br/>
+func newRequestHandler(strg *storage.Storage) httpserver.RequestHandler {
+	return func(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, `vmstorage - a component of VictoriaMetrics cluster<br/>
 			<a href="https://docs.victoriametrics.com/victoriametrics/cluster-victoriametrics/">docs</a><br>
 `)
-		return true
+			return true
+		}
+		return requestHandler(w, r, strg)
 	}
+}
 
+func requestHandler(w http.ResponseWriter, r *http.Request, strg *storage.Storage) bool {
+	path := r.URL.Path
 	if path == "/internal/force_merge" {
 		if !httpserver.CheckAuthFlag(w, r, forceMergeAuthKey) {
 			return true
@@ -290,7 +278,7 @@ func (api *VMStorage) requestHandler(w http.ResponseWriter, r *http.Request) boo
 			defer activeForceMerges.Dec()
 			logger.Infof("forced merge for partition_prefix=%q has been started", partitionNamePrefix)
 			startTime := time.Now()
-			if err := api.s.ForceMergePartitions(partitionNamePrefix); err != nil {
+			if err := strg.ForceMergePartitions(partitionNamePrefix); err != nil {
 				logger.Errorf("error in forced merge for partition_prefix=%q: %s", partitionNamePrefix, err)
 				return
 			}
@@ -303,7 +291,7 @@ func (api *VMStorage) requestHandler(w http.ResponseWriter, r *http.Request) boo
 			return true
 		}
 		logger.Infof("flushing storage to make pending data available for reading")
-		api.s.DebugFlush()
+		strg.DebugFlush()
 		return true
 	}
 
@@ -323,7 +311,7 @@ func (api *VMStorage) requestHandler(w http.ResponseWriter, r *http.Request) boo
 		}
 		logger.Infof("enabling logging of new series for the next %s. This may increase resource usage during this period.", time.Duration(dealine)*time.Second)
 		endTime := fasttime.UnixTimestamp() + uint64(dealine)
-		api.s.SetLogNewSeriesUntil(endTime)
+		strg.SetLogNewSeriesUntil(endTime)
 		fmt.Fprintf(w, `{"status":"success","data":{"logEndTime":%q}}`, time.Unix(int64(endTime), 0))
 		return true
 	}
@@ -339,13 +327,13 @@ func (api *VMStorage) requestHandler(w http.ResponseWriter, r *http.Request) boo
 	case "/create":
 		snapshotsCreateTotal.Inc()
 		w.Header().Set("Content-Type", "application/json")
-		snapshotName := api.s.MustCreateSnapshot()
+		snapshotName := strg.MustCreateSnapshot()
 
 		// Verify whether the client already closed the connection.
 		// In this case it is better to drop the created snapshot, since the client isn't interested in it.
 		if err := r.Context().Err(); err != nil {
 			logger.Infof("deleting already created snapshot at %s because the client canceled the request", snapshotName)
-			if err := api.deleteSnapshot(snapshotName); err != nil {
+			if err := deleteSnapshot(strg, snapshotName); err != nil {
 				logger.Infof("cannot delete just created snapshot: %s", err)
 				return true
 			}
@@ -357,7 +345,7 @@ func (api *VMStorage) requestHandler(w http.ResponseWriter, r *http.Request) boo
 	case "/list":
 		snapshotsListTotal.Inc()
 		w.Header().Set("Content-Type", "application/json")
-		snapshots := api.s.MustListSnapshots()
+		snapshots := strg.MustListSnapshots()
 		fmt.Fprintf(w, `{"status":"ok","snapshots":[`)
 		if len(snapshots) > 0 {
 			for _, snapshot := range snapshots[:len(snapshots)-1] {
@@ -371,7 +359,7 @@ func (api *VMStorage) requestHandler(w http.ResponseWriter, r *http.Request) boo
 		snapshotsDeleteTotal.Inc()
 		w.Header().Set("Content-Type", "application/json")
 		snapshotName := r.FormValue("snapshot")
-		if err := api.deleteSnapshot(snapshotName); err != nil {
+		if err := deleteSnapshot(strg, snapshotName); err != nil {
 			jsonResponseError(w, err)
 			snapshotsDeleteErrorsTotal.Inc()
 			return true
@@ -381,10 +369,9 @@ func (api *VMStorage) requestHandler(w http.ResponseWriter, r *http.Request) boo
 	case "/delete_all":
 		snapshotsDeleteAllTotal.Inc()
 		w.Header().Set("Content-Type", "application/json")
-		snapshots := api.s.MustListSnapshots()
+		snapshots := strg.MustListSnapshots()
 		for _, snapshotName := range snapshots {
-			// TODO(@rtm0): Use VMStorage.deleteSnapshot()?
-			if err := api.s.DeleteSnapshot(snapshotName); err != nil {
+			if err := strg.DeleteSnapshot(snapshotName); err != nil {
 				err = fmt.Errorf("cannot delete snapshot %q: %w", snapshotName, err)
 				jsonResponseError(w, err)
 				snapshotsDeleteAllErrorsTotal.Inc()
@@ -398,6 +385,50 @@ func (api *VMStorage) requestHandler(w http.ResponseWriter, r *http.Request) boo
 	}
 }
 
+func deleteSnapshot(strg *storage.Storage, snapshotName string) error {
+	snapshots := strg.MustListSnapshots()
+	for _, snName := range snapshots {
+		if snName == snapshotName {
+			if err := strg.DeleteSnapshot(snName); err != nil {
+				return fmt.Errorf("cannot delete snapshot %q: %w", snName, err)
+			}
+			return nil
+		}
+	}
+	return fmt.Errorf("cannot find snapshot %q", snapshotName)
+}
+
+func initStaleSnapshotsRemover(strg *storage.Storage) {
+	staleSnapshotsRemoverCh = make(chan struct{})
+	if snapshotsMaxAge.Duration() <= 0 {
+		return
+	}
+	snapshotsMaxAgeDur := snapshotsMaxAge.Duration()
+	staleSnapshotsRemoverWG.Go(func() {
+		d := timeutil.AddJitterToDuration(time.Second * 11)
+		t := time.NewTicker(d)
+		defer t.Stop()
+		for {
+			select {
+			case <-staleSnapshotsRemoverCh:
+				return
+			case <-t.C:
+			}
+			strg.MustDeleteStaleSnapshots(snapshotsMaxAgeDur)
+		}
+	})
+}
+
+func stopStaleSnapshotsRemover() {
+	close(staleSnapshotsRemoverCh)
+	staleSnapshotsRemoverWG.Wait()
+}
+
+var (
+	staleSnapshotsRemoverCh chan struct{}
+	staleSnapshotsRemoverWG sync.WaitGroup
+)
+
 var (
 	activeForceMerges = metrics.NewCounter("vm_active_force_merges")
 
@@ -412,9 +443,7 @@ var (
 	snapshotsDeleteAllErrorsTotal = metrics.NewCounter(`vm_http_request_errors_total{path="/snapshot/delete_all"}`)
 )
 
-// TODO(@rtm0): Move to metrics.go.
-func (api *VMStorage) writeStorageMetrics(w io.Writer) {
-	strg := api.s
+func writeStorageMetrics(w io.Writer, strg *storage.Storage) {
 	var m storage.Metrics
 	strg.UpdateMetrics(&m)
 	tm := &m.TableMetrics
@@ -638,7 +667,7 @@ func (api *VMStorage) writeStorageMetrics(w io.Writer) {
 	metrics.WriteGaugeUint64(w, `vm_downsampling_partitions_scheduled`, tm.ScheduledDownsamplingPartitions)
 	metrics.WriteGaugeUint64(w, `vm_downsampling_partitions_scheduled_size_bytes`, tm.ScheduledDownsamplingPartitionsSize)
 
-	metrics.WriteGaugeUint64(w, `vm_search_max_unique_timeseries`, uint64(api.maxUniqueTimeSeriesCalculated))
+	metrics.WriteGaugeUint64(w, `vm_search_max_unique_timeseries`, uint64(servers.GetMaxUniqueTimeSeries()))
 
 	metrics.WriteGaugeUint64(w, `vm_metrics_metadata_storage_items`, m.MetadataStorageItemsCurrent)
 	metrics.WriteCounterUint64(w, `vm_metrics_metadata_storage_size_bytes`, m.MetadataStorageCurrentSizeBytes)

app/vmstorage/servers/vminsert.go

@@ -0,0 +1,55 @@
+package servers
+
+import (
+	"flag"
+	"fmt"
+	"time"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage/metricsmetadata"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/vminsertapi"
+)
+
+var (
+	precisionBits = flag.Int("precisionBits", 64, "The number of precision bits to store per each value. Lower precision bits improves data compression "+
+		"at the cost of precision loss")
+	vminsertConnsShutdownDuration = flag.Duration("storage.vminsertConnsShutdownDuration", 10*time.Second, "The time needed for gradual closing of vminsert connections during "+
+		"graceful shutdown. Bigger duration reduces spikes in CPU, RAM and disk IO load on the remaining vmstorage nodes during rolling restart. "+
+		"Smaller duration reduces the time needed to close all the vminsert connections, thus reducing the time for graceful shutdown. "+
+		"Configured value must always be lower than the graceful shutdown period configured by the orchestration platform (terminationGracePeriodSeconds for Kubernetes). "+
+		"See https://docs.victoriametrics.com/victoriametrics/cluster-victoriametrics/#improving-re-routing-performance-during-restart")
+)
+
+// NewVMInsertServer starts vminsertapi.VMInsertServer at the given addr serving the given storage.
+func NewVMInsertServer(addr string, storage *storage.Storage) (*vminsertapi.VMInsertServer, error) {
+	if err := encoding.CheckPrecisionBits(uint8(*precisionBits)); err != nil {
+		return nil, fmt.Errorf("invalid -precisionBits: %w", err)
+	}
+	api := &vminsertAPI{
+		storage: storage,
+	}
+
+	return vminsertapi.NewVMInsertServer(addr, *vminsertConnsShutdownDuration, "vminsert", api, nil)
+}
+
+type vminsertAPI struct {
+	storage *storage.Storage
+}
+
+// WriteRows implements lib/vminsertapi.API interface
+func (v *vminsertAPI) WriteRows(rows []storage.MetricRow) error {
+	v.storage.AddRows(rows, uint8(*precisionBits))
+	return nil
+}
+
+// WriteMetadata implements lib/vminsertapi.API interface
+func (v *vminsertAPI) WriteMetadata(rows []metricsmetadata.Row) error {
+	v.storage.AddMetadataRows(rows)
+	return nil
+}
+
+// IsReadOnly implements lib/vminsertapi.API interface
+func (v *vminsertAPI) IsReadOnly() bool {
+	return v.storage.IsReadOnly()
+}

app/vmstorage/servers/vmselect.go

@@ -1,4 +1,4 @@
-package main
+package servers
 
 import (
 	"flag"
@@ -6,21 +6,17 @@ import (
 	"sync"
 	"time"
 
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/memory"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/querytracer"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage/metricnamestats"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage/metricsmetadata"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/timeutil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/vmselectapi"
 )
 
 var (
-	precisionBits = flag.Int("precisionBits", 64, "The number of precision bits to store per each value. Lower precision bits improves data compression "+
-		"at the cost of precision loss")
 	maxUniqueTimeseries = flag.Int("search.maxUniqueTimeseries", 0, "The maximum number of unique time series, which can be scanned during every query. "+
 		"This allows protecting against heavy queries, which select unexpectedly high number of series. When set to zero, the limit is automatically calculated based on -search.maxConcurrentRequests (inversely proportional) and memory available to the process (proportional). See also -search.max* command-line flags at vmselect")
 	maxTagKeys = flag.Int("search.maxTagKeys", 100e3, "The maximum number of tag keys returned per search. "+
@@ -28,110 +24,46 @@ var (
 	maxTagValues = flag.Int("search.maxTagValues", 100e3, "The maximum number of tag values returned per search. "+
 		"See also -search.maxLabelsAPISeries and -search.maxLabelsAPIDuration")
 	maxTagValueSuffixesPerSearch = flag.Int("search.maxTagValueSuffixesPerSearch", 100e3, "The maximum number of tag value suffixes returned from /metrics/find")
-	snapshotsMaxAge              = flagutil.NewRetentionDuration("snapshotsMaxAge", "3d", "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")
+	maxConcurrentRequests        = flag.Int("search.maxConcurrentRequests", 2*cgroup.AvailableCPUs(), "The maximum number of concurrent vmselect requests "+
+		"the vmstorage can process at -vmselectAddr. It shouldn't be high, since a single request usually saturates a CPU core, and 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 incoming vmselect request waits for execution "+
+		"when -search.maxConcurrentRequests limit is reached")
+
+	disableRPCCompression = flag.Bool("rpc.disableCompression", false, "Whether to disable compression of the data sent from vmstorage to vmselect. "+
+		"This reduces CPU usage at the cost of higher network bandwidth usage")
 )
 
-// newVMStorage creates a new instance of of VMStorage.
-//
-// The created VMStorage instance takes ownership of s.
-func newVMStorage(s *storage.Storage, maxConcurrentRequests int) *VMStorage {
-	if err := encoding.CheckPrecisionBits(uint8(*precisionBits)); err != nil {
-		logger.Fatalf("invalid -precisionBits: %d", err)
+var (
+	maxUniqueTimeseriesValue     int
+	maxUniqueTimeseriesValueOnce sync.Once
+)
+
+// NewVMSelectServer starts new server at the given addr, which serves vmselect requests from the given s.
+func NewVMSelectServer(addr string, s *storage.Storage) (*vmselectapi.Server, error) {
+	api := &vmstorageAPI{
+		s: s,
 	}
-
-	maxUniqueTimeseriesCalculated := *maxUniqueTimeseries
-	if maxUniqueTimeseriesCalculated <= 0 {
-		maxUniqueTimeseriesCalculated = calculateMaxUniqueTimeseries(maxConcurrentRequests, memory.Remaining())
+	limits := vmselectapi.Limits{
+		MaxLabelNames:                 *maxTagKeys,
+		MaxLabelValues:                *maxTagValues,
+		MaxTagValueSuffixes:           *maxTagValueSuffixesPerSearch,
+		MaxConcurrentRequests:         *maxConcurrentRequests,
+		MaxConcurrentRequestsFlagName: "search.maxConcurrentRequests",
+		MaxQueueDuration:              *maxQueueDuration,
+		MaxQueueDurationFlagName:      "search.maxQueueDuration",
 	}
-
-	vms := &VMStorage{
-		s:                             s,
-		maxUniqueTimeseries:           *maxUniqueTimeseries,
-		maxUniqueTimeSeriesCalculated: maxUniqueTimeseriesCalculated,
-		staleSnapshotsRemoverCh:       make(chan struct{}),
-	}
-	vms.initStaleSnapshotsRemover()
-	return vms
+	return vmselectapi.NewServer(addr, api, limits, *disableRPCCompression)
 }
 
-// calculateMaxUniqueTimeseries calculates the maxUniqueTimeseries based on the
-// available system resources.
-func calculateMaxUniqueTimeseries(maxConcurrentRequests, remainingMemory int) int {
-	if maxConcurrentRequests <= 0 {
-		// This line should NOT be reached unless the user has set an incorrect `search.maxConcurrentRequests`.
-		// In such cases, fallback to unlimited.
-		logger.Warnf("limiting -search.maxUniqueTimeseries to %v because -search.maxConcurrentRequests=%d.", 2e9, maxConcurrentRequests)
-		return 2e9
-	}
-
-	// Calculate the max metrics limit for a single request in the worst-case concurrent scenario.
-	// The approximate size of 1 unique series that could occupy in the vmstorage is 200 bytes.
-	mts := remainingMemory / 200 / maxConcurrentRequests
-	logger.Infof("limiting -search.maxUniqueTimeseries to %d according to -search.maxConcurrentRequests=%d and remaining memory=%d bytes. To increase the limit, reduce -search.maxConcurrentRequests or increase memory available to the process.", mts, maxConcurrentRequests, remainingMemory)
-	return mts
+// vmstorageAPI impelements vmselectapi.API
+type vmstorageAPI struct {
+	s *storage.Storage
 }
 
-// VMStorage impelements vmselectapi.API and vminsertapi.API.
-type VMStorage struct {
-	s                             *storage.Storage
-	maxUniqueTimeseries           int
-	maxUniqueTimeSeriesCalculated int
-	staleSnapshotsRemoverCh       chan struct{}
-	staleSnapshotsRemoverWG       sync.WaitGroup
-}
-
-func (api *VMStorage) initStaleSnapshotsRemover() {
-	if snapshotsMaxAge.Duration() <= 0 {
-		return
-	}
-	snapshotsMaxAgeDuration := snapshotsMaxAge.Duration()
-	api.staleSnapshotsRemoverWG.Go(func() {
-		d := timeutil.AddJitterToDuration(time.Second * 11)
-		t := time.NewTicker(d)
-		defer t.Stop()
-		for {
-			select {
-			case <-api.staleSnapshotsRemoverCh:
-				return
-			case <-t.C:
-			}
-			api.s.MustDeleteStaleSnapshots(snapshotsMaxAgeDuration)
-		}
-	})
-}
-
-func (api *VMStorage) Stop() {
-	close(api.staleSnapshotsRemoverCh)
-	api.staleSnapshotsRemoverWG.Wait()
-	api.s.MustClose()
-}
-
-// WriteRows writes metric rows to the storage.
-//
-// The caller should limit the number of concurrent calls to WriteRows() in
-// order to limit memory usage.
-func (api *VMStorage) WriteRows(rows []storage.MetricRow) error {
-	api.s.AddRows(rows, uint8(*precisionBits))
-	return nil
-}
-
-// WriteMetadata writes metrics metadata to storage.
-//
-// The caller should limit the number of concurrent calls to WriteMetadata() in
-// order to limit memory usage.
-func (api *VMStorage) WriteMetadata(rows []metricsmetadata.Row) error {
-	api.s.AddMetadataRows(rows)
-	return nil
-}
-
-// IsReadOnly returns true is the storage is in read-only mode.
-func (api *VMStorage) IsReadOnly() bool {
-	return api.s.IsReadOnly()
-}
-
-func (api *VMStorage) InitSearch(qt *querytracer.Tracer, sq *storage.SearchQuery, deadline uint64) (vmselectapi.BlockIterator, error) {
+func (api *vmstorageAPI) InitSearch(qt *querytracer.Tracer, sq *storage.SearchQuery, deadline uint64) (vmselectapi.BlockIterator, error) {
 	tr := sq.GetTimeRange()
-	maxMetrics := api.getMaxMetrics(sq.MaxMetrics)
+	maxMetrics := getMaxMetrics(sq.MaxMetrics)
 	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
 	if err != nil {
 		return nil, err
@@ -148,15 +80,158 @@ func (api *VMStorage) InitSearch(qt *querytracer.Tracer, sq *storage.SearchQuery
 	return bi, nil
 }
 
-func (api *VMStorage) getMaxMetrics(searchQueryLimit int) int {
-	if searchQueryLimit <= 0 {
-		return api.maxUniqueTimeSeriesCalculated
+func (api *vmstorageAPI) SearchMetricNames(qt *querytracer.Tracer, sq *storage.SearchQuery, deadline uint64) ([]string, error) {
+	tr := sq.GetTimeRange()
+	maxMetrics := sq.MaxMetrics
+	if maxMetrics <= 0 {
+		// fallback to maxUniqueTimeSeries if no limit is provided,
+		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
+		maxMetrics = GetMaxUniqueTimeSeries()
 	}
-	// searchQueryLimit cannot exceed `-search.maxUniqueTimeseries`
-	if api.maxUniqueTimeseries != 0 && searchQueryLimit > api.maxUniqueTimeseries {
-		searchQueryLimit = api.maxUniqueTimeseries
+	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
+	if err != nil {
+		return nil, err
 	}
-	return searchQueryLimit
+	if len(tfss) == 0 {
+		return nil, fmt.Errorf("missing tag filters")
+	}
+	return api.s.SearchMetricNames(qt, tfss, tr, maxMetrics, deadline)
+}
+
+func (api *vmstorageAPI) LabelValues(qt *querytracer.Tracer, sq *storage.SearchQuery, labelName string, maxLabelValues int, deadline uint64) ([]string, error) {
+	tr := sq.GetTimeRange()
+	maxMetrics := sq.MaxMetrics
+	if maxMetrics <= 0 {
+		// fallback to maxUniqueTimeSeries if no limit is provided,
+		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
+		maxMetrics = GetMaxUniqueTimeSeries()
+	}
+	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
+	if err != nil {
+		return nil, err
+	}
+	return api.s.SearchLabelValues(qt, sq.AccountID, sq.ProjectID, labelName, tfss, tr, maxLabelValues, maxMetrics, deadline)
+}
+
+func (api *vmstorageAPI) TagValueSuffixes(qt *querytracer.Tracer, accountID, projectID uint32, tr storage.TimeRange, tagKey, tagValuePrefix string, delimiter byte,
+	maxSuffixes int, deadline uint64) ([]string, error) {
+	suffixes, err := api.s.SearchTagValueSuffixes(qt, accountID, projectID, tr, tagKey, tagValuePrefix, delimiter, maxSuffixes, deadline)
+	if err != nil {
+		return nil, err
+	}
+	if len(suffixes) >= maxSuffixes {
+		return nil, fmt.Errorf("more than -search.maxTagValueSuffixesPerSearch=%d suffixes returned; "+
+			"either narrow down the search or increase -search.maxTagValueSuffixesPerSearch command-line flag value", maxSuffixes)
+	}
+	return suffixes, nil
+}
+
+func (api *vmstorageAPI) LabelNames(qt *querytracer.Tracer, sq *storage.SearchQuery, maxLabelNames int, deadline uint64) ([]string, error) {
+	tr := sq.GetTimeRange()
+	maxMetrics := sq.MaxMetrics
+	if maxMetrics <= 0 {
+		// fallback to maxUniqueTimeSeries if no limit is provided,
+		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
+		maxMetrics = GetMaxUniqueTimeSeries()
+	}
+	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
+	if err != nil {
+		return nil, err
+	}
+	return api.s.SearchLabelNames(qt, sq.AccountID, sq.ProjectID, tfss, tr, maxLabelNames, maxMetrics, deadline)
+}
+
+func (api *vmstorageAPI) SeriesCount(_ *querytracer.Tracer, accountID, projectID uint32, deadline uint64) (uint64, error) {
+	return api.s.GetSeriesCount(accountID, projectID, deadline)
+}
+
+func (api *vmstorageAPI) Tenants(qt *querytracer.Tracer, tr storage.TimeRange, deadline uint64) ([]string, error) {
+	return api.s.SearchTenants(qt, tr, deadline)
+}
+
+func (api *vmstorageAPI) TSDBStatus(qt *querytracer.Tracer, sq *storage.SearchQuery, focusLabel string, topN int, deadline uint64) (*storage.TSDBStatus, error) {
+	tr := sq.GetTimeRange()
+	maxMetrics := sq.MaxMetrics
+	if maxMetrics <= 0 {
+		// fallback to maxUniqueTimeSeries if no limit is provided,
+		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
+		maxMetrics = GetMaxUniqueTimeSeries()
+	}
+	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
+	if err != nil {
+		return nil, err
+	}
+	date := uint64(sq.MinTimestamp) / (24 * 3600 * 1000)
+	return api.s.GetTSDBStatus(qt, sq.AccountID, sq.ProjectID, tfss, date, focusLabel, topN, maxMetrics, deadline)
+}
+
+func (api *vmstorageAPI) DeleteSeries(qt *querytracer.Tracer, sq *storage.SearchQuery, deadline uint64) (int, error) {
+	tr := sq.GetTimeRange()
+	maxMetrics := sq.MaxMetrics
+	if maxMetrics <= 0 {
+		// fallback to maxUniqueTimeSeries if no limit is provided,
+		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
+		maxMetrics = GetMaxUniqueTimeSeries()
+	}
+	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
+	if err != nil {
+		return 0, err
+	}
+	if len(tfss) == 0 {
+		return 0, fmt.Errorf("missing tag filters")
+	}
+	return api.s.DeleteSeries(qt, tfss, maxMetrics)
+}
+
+func (api *vmstorageAPI) RegisterMetricNames(qt *querytracer.Tracer, mrs []storage.MetricRow, _ uint64) error {
+	api.s.RegisterMetricNames(qt, mrs)
+	return nil
+}
+
+func (api *vmstorageAPI) GetMetricNamesUsageStats(qt *querytracer.Tracer, tt *storage.TenantToken, limit, le int, matchPattern string, _ uint64) (metricnamestats.StatsResult, error) {
+	return api.s.GetMetricNamesStats(qt, tt, limit, le, matchPattern), nil
+}
+
+func (api *vmstorageAPI) ResetMetricNamesUsageStats(qt *querytracer.Tracer, _ uint64) error {
+	api.s.ResetMetricNamesStats(qt)
+	return nil
+}
+
+func (api *vmstorageAPI) setupTfss(qt *querytracer.Tracer, sq *storage.SearchQuery, tr storage.TimeRange, maxMetrics int, deadline uint64) ([]*storage.TagFilters, error) {
+	tfss := make([]*storage.TagFilters, 0, len(sq.TagFilterss))
+	accountID := sq.AccountID
+	projectID := sq.ProjectID
+	for _, tagFilters := range sq.TagFilterss {
+		tfs := storage.NewTagFilters(accountID, projectID)
+		for i := range tagFilters {
+			tf := &tagFilters[i]
+			if string(tf.Key) == "__graphite__" {
+				query := tf.Value
+				qtChild := qt.NewChild("searching for series matching __graphite__=%q", query)
+				paths, err := api.s.SearchGraphitePaths(qtChild, accountID, projectID, tr, query, maxMetrics, deadline)
+				qtChild.Donef("found %d series", len(paths))
+				if err != nil {
+					return nil, fmt.Errorf("error when searching for Graphite paths for query %q: %w", query, err)
+				}
+				if len(paths) >= maxMetrics {
+					return nil, fmt.Errorf("more than %d time series match Graphite query %q; "+
+						"either narrow down the query or increase the corresponding -search.max* command-line flag value at vmselect nodes; "+
+						"see https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/#resource-usage-limits", maxMetrics, query)
+				}
+				tfs.AddGraphiteQuery(query, paths, tf.IsNegative)
+				continue
+			}
+			if err := tfs.Add(tf.Key, tf.Value, tf.IsNegative, tf.IsRegexp); err != nil {
+				return nil, fmt.Errorf("cannot parse tag filter %s: %w", tf, err)
+			}
+		}
+		tfss = append(tfss, tfs)
+	}
+	return tfss, nil
+}
+
+func (api *vmstorageAPI) GetMetadataRecords(qt *querytracer.Tracer, tt *storage.TenantToken, limit int, metricName string, deadline uint64) ([]*metricsmetadata.Row, error) {
+	return api.s.GetMetadataRows(qt, tt, limit, metricName, deadline)
 }
 
 // blockIterator implements vmselectapi.BlockIterator
@@ -197,197 +272,41 @@ func (bi *blockIterator) Error() error {
 	return bi.sr.Error()
 }
 
-// SearchMetricNames returns metric names for the given tfss on the given tr.
-func (api *VMStorage) SearchMetricNames(qt *querytracer.Tracer, sq *storage.SearchQuery, deadline uint64) ([]string, error) {
-	tr := sq.GetTimeRange()
-	maxMetrics := sq.MaxMetrics
-	if maxMetrics <= 0 {
-		// fallback to maxUniqueTimeSeries if no limit is provided,
-		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
-		maxMetrics = api.maxUniqueTimeSeriesCalculated
+func getMaxMetrics(searchQueryLimit int) int {
+	if searchQueryLimit <= 0 {
+		return GetMaxUniqueTimeSeries()
 	}
-	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
-	if err != nil {
-		return nil, err
+	// searchQueryLimit cannot exceed `-search.maxUniqueTimeseries`
+	if *maxUniqueTimeseries != 0 && searchQueryLimit > *maxUniqueTimeseries {
+		searchQueryLimit = *maxUniqueTimeseries
 	}
-	if len(tfss) == 0 {
-		return nil, fmt.Errorf("missing tag filters")
-	}
-	return api.s.SearchMetricNames(qt, tfss, tr, maxMetrics, deadline)
+	return searchQueryLimit
 }
 
-// SearchLabelValues searches for label values for the given labelName, tfss and
-// tr.
-func (api *VMStorage) LabelValues(qt *querytracer.Tracer, sq *storage.SearchQuery, labelName string, maxLabelValues int, deadline uint64) ([]string, error) {
-	tr := sq.GetTimeRange()
-	if maxLabelValues <= 0 || maxLabelValues > *maxTagValues {
-		maxLabelValues = *maxTagValues
-	}
-	maxMetrics := sq.MaxMetrics
-	if maxMetrics <= 0 {
-		// fallback to maxUniqueTimeSeries if no limit is provided,
-		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
-		maxMetrics = api.maxUniqueTimeSeriesCalculated
-	}
-	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
-	if err != nil {
-		return nil, err
-	}
-	return api.s.SearchLabelValues(qt, sq.AccountID, sq.ProjectID, labelName, tfss, tr, maxLabelValues, maxMetrics, deadline)
-}
-
-// TagValueSuffixes returns all the tag value suffixes for the given tagKey and
-// tagValuePrefix on the given tr.
-//
-// This allows implementing
-// https://graphite-api.readthedocs.io/en/latest/api.html#metrics-find or
-// similar APIs.
-func (api *VMStorage) TagValueSuffixes(qt *querytracer.Tracer, accountID, projectID uint32, tr storage.TimeRange, tagKey, tagValuePrefix string, delimiter byte,
-	maxSuffixes int, deadline uint64) ([]string, error) {
-	if maxSuffixes <= 0 || maxSuffixes > *maxTagValueSuffixesPerSearch {
-		maxSuffixes = *maxTagValueSuffixesPerSearch
-	}
-	suffixes, err := api.s.SearchTagValueSuffixes(qt, accountID, projectID, tr, tagKey, tagValuePrefix, delimiter, maxSuffixes, deadline)
-	if err != nil {
-		return nil, err
-	}
-	if len(suffixes) >= maxSuffixes {
-		return nil, fmt.Errorf("more than -search.maxTagValueSuffixesPerSearch=%d suffixes returned; "+
-			"either narrow down the search or increase -search.maxTagValueSuffixesPerSearch command-line flag value", maxSuffixes)
-	}
-	return suffixes, nil
-}
-
-// SearchLabelNames searches for tag keys matching the given tfss on tr.
-func (api *VMStorage) LabelNames(qt *querytracer.Tracer, sq *storage.SearchQuery, maxLabelNames int, deadline uint64) ([]string, error) {
-	tr := sq.GetTimeRange()
-	if maxLabelNames <= 0 || maxLabelNames > *maxTagKeys {
-		maxLabelNames = *maxTagKeys
-	}
-	maxMetrics := sq.MaxMetrics
-	if maxMetrics <= 0 {
-		// fallback to maxUniqueTimeSeries if no limit is provided,
-		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
-		maxMetrics = api.maxUniqueTimeSeriesCalculated
-	}
-	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
-	if err != nil {
-		return nil, err
-	}
-	return api.s.SearchLabelNames(qt, sq.AccountID, sq.ProjectID, tfss, tr, maxLabelNames, maxMetrics, deadline)
-}
-
-func (api *VMStorage) SeriesCount(_ *querytracer.Tracer, accountID, projectID uint32, deadline uint64) (uint64, error) {
-	return api.s.GetSeriesCount(accountID, projectID, deadline)
-}
-
-func (api *VMStorage) Tenants(qt *querytracer.Tracer, tr storage.TimeRange, deadline uint64) ([]string, error) {
-	return api.s.SearchTenants(qt, tr, deadline)
-}
-
-// GetTSDBStatus returns TSDB status for given filters on the given date.
-func (api *VMStorage) TSDBStatus(qt *querytracer.Tracer, sq *storage.SearchQuery, focusLabel string, topN int, deadline uint64) (*storage.TSDBStatus, error) {
-	tr := sq.GetTimeRange()
-	maxMetrics := sq.MaxMetrics
-	if maxMetrics <= 0 {
-		// fallback to maxUniqueTimeSeries if no limit is provided,
-		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
-		maxMetrics = api.maxUniqueTimeSeriesCalculated
-	}
-	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
-	if err != nil {
-		return nil, err
-	}
-	date := uint64(sq.MinTimestamp) / (24 * 3600 * 1000)
-	return api.s.GetTSDBStatus(qt, sq.AccountID, sq.ProjectID, tfss, date, focusLabel, topN, maxMetrics, deadline)
-}
-
-// DeleteSeries deletes series matching tfss.
-//
-// Returns the number of deleted series.
-func (api *VMStorage) DeleteSeries(qt *querytracer.Tracer, sq *storage.SearchQuery, deadline uint64) (int, error) {
-	tr := sq.GetTimeRange()
-	maxMetrics := sq.MaxMetrics
-	if maxMetrics <= 0 {
-		// fallback to maxUniqueTimeSeries if no limit is provided,
-		// see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7857
-		maxMetrics = api.maxUniqueTimeSeriesCalculated
-	}
-	tfss, err := api.setupTfss(qt, sq, tr, maxMetrics, deadline)
-	if err != nil {
-		return 0, err
-	}
-	if len(tfss) == 0 {
-		return 0, fmt.Errorf("missing tag filters")
-	}
-	return api.s.DeleteSeries(qt, tfss, maxMetrics)
-}
-
-func (api *VMStorage) RegisterMetricNames(qt *querytracer.Tracer, mrs []storage.MetricRow, _ uint64) error {
-	api.s.RegisterMetricNames(qt, mrs)
-	return nil
-}
-
-// GetMetricNamesUsageStats returns metric name usage stats.
-func (api *VMStorage) GetMetricNamesUsageStats(qt *querytracer.Tracer, tt *storage.TenantToken, limit, le int, matchPattern string, _ uint64) (metricnamestats.StatsResult, error) {
-	return api.s.GetMetricNamesStats(qt, tt, limit, le, matchPattern), nil
-}
-
-// ResetMetricNamesStats resets state for metric names usage tracker
-func (api *VMStorage) ResetMetricNamesUsageStats(qt *querytracer.Tracer, _ uint64) error {
-	api.s.ResetMetricNamesStats(qt)
-	return nil
-}
-
-func (api *VMStorage) setupTfss(qt *querytracer.Tracer, sq *storage.SearchQuery, tr storage.TimeRange, maxMetrics int, deadline uint64) ([]*storage.TagFilters, error) {
-	tfss := make([]*storage.TagFilters, 0, len(sq.TagFilterss))
-	accountID := sq.AccountID
-	projectID := sq.ProjectID
-	for _, tagFilters := range sq.TagFilterss {
-		tfs := storage.NewTagFilters(accountID, projectID)
-		for i := range tagFilters {
-			tf := &tagFilters[i]
-			if string(tf.Key) == "__graphite__" {
-				query := tf.Value
-				qtChild := qt.NewChild("searching for series matching __graphite__=%q", query)
-				paths, err := api.s.SearchGraphitePaths(qtChild, accountID, projectID, tr, query, maxMetrics, deadline)
-				qtChild.Donef("found %d series", len(paths))
-				if err != nil {
-					return nil, fmt.Errorf("error when searching for Graphite paths for query %q: %w", query, err)
-				}
-				if len(paths) >= maxMetrics {
-					return nil, fmt.Errorf("more than %d time series match Graphite query %q; "+
-						"either narrow down the query or increase the corresponding -search.max* command-line flag value at vmselect nodes; "+
-						"see https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/#resource-usage-limits", maxMetrics, query)
-				}
-				tfs.AddGraphiteQuery(query, paths, tf.IsNegative)
-				continue
-			}
-			if err := tfs.Add(tf.Key, tf.Value, tf.IsNegative, tf.IsRegexp); err != nil {
-				return nil, fmt.Errorf("cannot parse tag filter %s: %w", tf, err)
-			}
+// GetMaxUniqueTimeSeries returns `-search.maxUniqueTimeseries` or the auto-calculated value based on available resources.
+// The calculation is split into calculateMaxUniqueTimeSeriesForResource for unit testing.
+func GetMaxUniqueTimeSeries() int {
+	maxUniqueTimeseriesValueOnce.Do(func() {
+		maxUniqueTimeseriesValue = *maxUniqueTimeseries
+		if maxUniqueTimeseriesValue <= 0 {
+			maxUniqueTimeseriesValue = calculateMaxUniqueTimeSeriesForResource(*maxConcurrentRequests, memory.Remaining())
 		}
-		tfss = append(tfss, tfs)
-	}
-	return tfss, nil
+	})
+	return maxUniqueTimeseriesValue
 }
 
-func (api *VMStorage) GetMetadataRecords(qt *querytracer.Tracer, tt *storage.TenantToken, limit int, metricName string, deadline uint64) ([]*metricsmetadata.Row, error) {
-	return api.s.GetMetadataRows(qt, tt, limit, metricName, deadline)
-}
-
-// deleteSnapshot deletes a snapshot by its name.
-//
-// Callers must wrap the call with wg.Add(1)...wg.Done().
-func (api *VMStorage) deleteSnapshot(snapshotName string) error {
-	snapshots := api.s.MustListSnapshots()
-	for _, snName := range snapshots {
-		if snName == snapshotName {
-			if err := api.s.DeleteSnapshot(snName); err != nil {
-				return fmt.Errorf("cannot delete snapshot %q: %w", snName, err)
-			}
-			return nil
-		}
+// calculateMaxUniqueTimeSeriesForResource calculate the max metrics limit calculated by available resources.
+func calculateMaxUniqueTimeSeriesForResource(maxConcurrentRequests, remainingMemory int) int {
+	if maxConcurrentRequests <= 0 {
+		// This line should NOT be reached unless the user has set an incorrect `search.maxConcurrentRequests`.
+		// In such cases, fallback to unlimited.
+		logger.Warnf("limiting -search.maxUniqueTimeseries to %v because -search.maxConcurrentRequests=%d.", 2e9, maxConcurrentRequests)
+		return 2e9
 	}
-	return fmt.Errorf("cannot find snapshot %q", snapshotName)
+
+	// Calculate the max metrics limit for a single request in the worst-case concurrent scenario.
+	// The approximate size of 1 unique series that could occupy in the vmstorage is 200 bytes.
+	mts := remainingMemory / 200 / maxConcurrentRequests
+	logger.Infof("limiting -search.maxUniqueTimeseries to %d according to -search.maxConcurrentRequests=%d and remaining memory=%d bytes. To increase the limit, reduce -search.maxConcurrentRequests or increase memory available to the process.", mts, maxConcurrentRequests, remainingMemory)
+	return mts
 }

app/vmstorage/servers/vmselect_test.go

@@ -1,18 +1,15 @@
-package main
+package servers
 
 import (
 	"math"
 	"strconv"
 	"testing"
-
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
-	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage"
 )
 
 func TestCalculateMaxMetricsLimitByResource(t *testing.T) {
 	f := func(maxConcurrentRequest, remainingMemory, expect int) {
 		t.Helper()
-		maxMetricsLimit := calculateMaxUniqueTimeseries(maxConcurrentRequest, remainingMemory)
+		maxMetricsLimit := calculateMaxUniqueTimeSeriesForResource(maxConcurrentRequest, remainingMemory)
 		if maxMetricsLimit != expect {
 			t.Fatalf("unexpected max metrics limit: got %d, want %d", maxMetricsLimit, expect)
 		}
@@ -40,14 +37,10 @@ func TestGetMaxMetrics(t *testing.T) {
 	defer func() {
 		*maxUniqueTimeseries = originalMaxUniqueTimeSeries
 	}()
-
-	maxConcurrentRequests := 2 * cgroup.AvailableCPUs()
 	f := func(searchQueryLimit, storageMaxUniqueTimeseries, expect int) {
 		t.Helper()
 		*maxUniqueTimeseries = storageMaxUniqueTimeseries
-		s := &storage.Storage{}
-		vmstorage := newVMStorage(s, maxConcurrentRequests)
-		maxMetrics := vmstorage.getMaxMetrics(searchQueryLimit)
+		maxMetrics := getMaxMetrics(searchQueryLimit)
 		if maxMetrics != expect {
 			t.Fatalf("unexpected max metrics: got %d, want %d", maxMetrics, expect)
 		}

app/vmui/packages/vmui/src/components/Configurators/QueryEditor/warningText.ts

@@ -1,7 +1,7 @@
-export const seriesFetchedWarning = `No match! 
+export const seriesFetchedWarning = `No match!
 This query hasn't selected any time series from database.
 Either the requested metrics are missing in the database,
 or there is a typo in series selector.`;
 
 export const partialWarning = `The shown results are marked as PARTIAL.
-The result is marked as partial if one or more vmstorage nodes failed to respond to the query.`;
+The result is marked as partial if one or more storage nodes failed to respond to the query.`;

app/vmui/packages/vmui/src/components/ExploreAlerts/RulesHeader/index.tsx

@@ -71,7 +71,7 @@ const RulesHeader = ({
           <TextField
             label="Search"
             value={search}
-            placeholder="Filter by rule, name or labels"
+            placeholder="Filter by group or rule name"
             startIcon={<SearchIcon />}
             onChange={onChangeSearch}
           />

app/vmui/packages/vmui/src/components/Main/Tabs/TabItem.tsx

@@ -1,6 +1,5 @@
 import { Component, FC, Ref } from "preact/compat";
 import classNames from "classnames";
-import { getCssVariable } from "../../../utils/theme";
 import { TabItemType } from "./Tabs";
 import TabItemWrapper from "./TabItemWrapper";
 import "./style.scss";
@@ -8,7 +7,6 @@ import "./style.scss";
 interface TabItemProps {
   activeItem: string
   item: TabItemType
-  color?: string
   onChange?: (value: string) => void
   activeNavRef: Ref<Component>
   isNavLink?: boolean
@@ -17,7 +15,6 @@ interface TabItemProps {
 const TabItem: FC<TabItemProps> = ({
   activeItem,
   item,
-  color = getCssVariable("color-primary"),
   activeNavRef,
   onChange,
   isNavLink
@@ -35,7 +32,6 @@ const TabItem: FC<TabItemProps> = ({
       })}
       isNavLink={isNavLink}
       to={item.value}
-      style={{ color: color }}
       onClick={createHandlerClickTab(item.value)}
       ref={activeItem === item.value ? activeNavRef : undefined}
     >

app/vmui/packages/vmui/src/components/Main/Tabs/TabItemWrapper.tsx

@@ -6,7 +6,6 @@ interface TabItemWrapperProps {
   to: string
   isNavLink?: boolean
   className: string
-  style: { color: string }
   children: ReactNode
   onClick: () => void
 }

app/vmui/packages/vmui/src/components/Main/Tabs/Tabs.tsx

@@ -1,6 +1,5 @@
 import { Component, FC, useRef, useState } from "preact/compat";
 import { ReactNode, useEffect } from "react";
-import { getCssVariable } from "../../../utils/theme";
 import TabItem from "./TabItem";
 import "./style.scss";
 import useWindowSize from "../../../hooks/useWindowSize";
@@ -15,7 +14,6 @@ export interface TabItemType {
 interface TabsProps {
   activeItem: string
   items: TabItemType[]
-  color?: string
   onChange?: (value: string) => void
   indicatorPlacement?: "bottom" | "top"
   isNavLink?: boolean
@@ -24,7 +22,6 @@ interface TabsProps {
 const Tabs: FC<TabsProps> = ({
   activeItem,
   items,
-  color = getCssVariable("color-primary"),
   onChange,
   indicatorPlacement = "bottom",
   isNavLink,
@@ -48,14 +45,13 @@ const Tabs: FC<TabsProps> = ({
         activeItem={activeItem}
         item={item}
         onChange={onChange}
-        color={color}
         activeNavRef={activeNavRef}
         isNavLink={isNavLink}
       />
     ))}
     <div
       className="vm-tabs__indicator"
-      style={{ ...indicatorPosition, borderColor: color }}
+      style={{ ...indicatorPosition }}
     />
   </div>;
 };

app/vmui/packages/vmui/src/components/Main/Tabs/style.scss

@@ -14,7 +14,7 @@
     align-items: center;
     justify-content: center;
     padding: $padding-global $padding-small;
-    color: inherit;
+    color: $color-primary;
     text-decoration: none;
     text-transform: capitalize;
     font-size: inherit;
@@ -46,5 +46,6 @@
     position: absolute;
     border-bottom: 2px solid;
     transition: width 200ms ease, left 300ms cubic-bezier(0.280, 0.840, 0.420, 1);
+    border-color: $color-primary;
   }
 }

app/vmui/packages/vmui/src/state/customPanel/reducer.test.ts

@@ -0,0 +1,35 @@
+import { afterEach, describe, expect, it, vi, type Mock } from "vitest";
+import { getFromStorage, saveToStorage } from "../../utils/storage";
+
+vi.mock("../../utils/storage", () => ({
+  getFromStorage: vi.fn(),
+  saveToStorage: vi.fn(),
+}));
+
+describe("customPanel reducer", () => {
+  afterEach(() => {
+    vi.resetAllMocks();
+    vi.resetModules();
+  });
+
+  it("persists reduceMemUsage under its own storage key", async () => {
+    const { reducer, initialCustomPanelState } = await import("./reducer");
+
+    reducer(initialCustomPanelState, { type: "TOGGLE_REDUCE_MEM_USAGE" });
+
+    expect(saveToStorage).toHaveBeenCalledWith("REDUCE_MEM_USAGE", true);
+    expect(saveToStorage).not.toHaveBeenCalledWith("TABLE_COMPACT", true);
+  });
+
+  it("hydrates reduceMemUsage from storage", async () => {
+    const getFromStorageMock = getFromStorage as Mock;
+    getFromStorageMock.mockImplementation((key: string) => {
+      if (key === "REDUCE_MEM_USAGE") return true;
+      return undefined;
+    });
+
+    const { initialCustomPanelState } = await import("./reducer");
+
+    expect(initialCustomPanelState.reduceMemUsage).toBe(true);
+  });
+});

app/vmui/packages/vmui/src/state/customPanel/reducer.ts

@@ -35,7 +35,7 @@ export const initialCustomPanelState: CustomPanelState = {
   isTracingEnabled: false,
   seriesLimits: limitsStorage ? JSON.parse(limitsStorage) : DEFAULT_MAX_SERIES,
   tableCompact: getFromStorage("TABLE_COMPACT") as boolean || false,
-  reduceMemUsage: false
+  reduceMemUsage: getFromStorage("REDUCE_MEM_USAGE") as boolean || false
 };
 
 export function reducer(state: CustomPanelState, action: CustomPanelAction): CustomPanelState {
@@ -69,7 +69,7 @@ export function reducer(state: CustomPanelState, action: CustomPanelAction): Cus
         tableCompact: !state.tableCompact
       };
     case "TOGGLE_REDUCE_MEM_USAGE":
-      saveToStorage("TABLE_COMPACT", !state.reduceMemUsage);
+      saveToStorage("REDUCE_MEM_USAGE", !state.reduceMemUsage);
       return {
         ...state,
         reduceMemUsage: !state.reduceMemUsage

app/vmui/packages/vmui/src/utils/storage.ts

@@ -7,6 +7,7 @@ export const ALL_STORAGE_KEYS = [
   "SERIES_LIMITS",
   "LEGEND_AUTO_COLLAPSE",
   "TABLE_COMPACT",
+  "REDUCE_MEM_USAGE",
   "TIMEZONE",
   "DISABLED_DEFAULT_TIMEZONE",
   "THEME",

apptest/model.go

@@ -79,24 +79,25 @@ type PrometheusWriteQuerier interface {
 
 // QueryOpts contains various params used for querying or ingesting data
 type QueryOpts struct {
-	Tenant         string
-	Timeout        string
-	Start          string
-	End            string
-	Time           string
-	Step           string
-	ExtraFilters   []string
-	ExtraLabels    []string
-	Trace          string
-	ReduceMemUsage string
-	MaxLookback    string
-	LatencyOffset  string
-	Format         string
-	NoCache        string
-	Headers        http.Header
-	From           string
-	Until          string
-	StorageStep    string
+	Tenant              string
+	Timeout             string
+	Start               string
+	End                 string
+	Time                string
+	Step                string
+	ExtraFilters        []string
+	ExtraLabels         []string
+	Trace               string
+	ReduceMemUsage      string
+	MaxLookback         string
+	LatencyOffset       string
+	Format              string
+	NoCache             string
+	Headers             http.Header
+	From                string
+	Until               string
+	StorageStep         string
+	DenyPartialResponse string
 }
 
 func (qos *QueryOpts) getHeaders() http.Header {
@@ -132,6 +133,7 @@ func (qos *QueryOpts) asURLValues() url.Values {
 	addNonEmpty("from", qos.From)
 	addNonEmpty("until", qos.Until)
 	addNonEmpty("storage_step", qos.StorageStep)
+	addNonEmpty("deny_partial_response", qos.DenyPartialResponse)
 
 	return uv
 }

apptest/tests/replication_test.go

@@ -1015,35 +1015,42 @@ func testGroupSkipSlowReplicas(tc *apptest.TestCase, opts *testGroupReplicationO
 func testGroupPartialResponse(tc *apptest.TestCase, opts *testGroupReplicationOpts) {
 	t := tc.T()
 
-	assertSeries := func(app *apptest.Vmselect, wantPartial bool) {
+	assertSeries := func(app *apptest.Vmselect, denyPartialResponse string, want *apptest.PrometheusAPIV1SeriesResponse) {
 		t.Helper()
 		tc.Assert(&apptest.AssertOptions{
 			Msg: "unexpected /api/v1/series response",
 			Got: func() any {
 				return app.PrometheusAPIV1Series(t, `{__name__=~".*"}`, apptest.QueryOpts{
-					Start: "2024-01-01T00:00:00Z",
-					End:   "2024-01-31T00:00:00Z",
+					Start:               "2024-01-01T00:00:00Z",
+					End:                 "2024-01-31T00:00:00Z",
+					DenyPartialResponse: denyPartialResponse,
 				}).Sort()
 			},
-			Want: &apptest.PrometheusAPIV1SeriesResponse{
-				Status:    "success",
-				IsPartial: wantPartial,
-			},
+			Want: want,
 			CmpOpts: []cmp.Option{
-				cmpopts.IgnoreFields(apptest.PrometheusAPIV1SeriesResponse{}, "Data"),
+				cmpopts.IgnoreFields(apptest.PrometheusAPIV1SeriesResponse{}, "Data", "Error"),
 			},
 		})
 	}
 
-	mustReturnPartialResponse := true
-	mustReturnFullResponse := false
+	allowPartialResponse := ""
+	denyPartialResponse := "1"
+
+	mustReturnPartialResponse := &apptest.PrometheusAPIV1SeriesResponse{
+		Status:    "success",
+		IsPartial: true,
+	}
+	mustReturnFullResponse := &apptest.PrometheusAPIV1SeriesResponse{
+		Status:    "success",
+		IsPartial: false,
+	}
 
 	// All vmstorage replicas are available so both vmselects must return full
 	// response.
-	assertSeries(opts.c.vmselect, mustReturnFullResponse)
-	assertSeries(opts.c.vmselectGroupRF, mustReturnFullResponse)
-	assertSeries(opts.c.vmselectGlobalRF, mustReturnFullResponse)
-	assertSeries(opts.c.vmselectGroupGlobalRF, mustReturnFullResponse)
+	assertSeries(opts.c.vmselect, allowPartialResponse, mustReturnFullResponse)
+	assertSeries(opts.c.vmselectGroupRF, allowPartialResponse, mustReturnFullResponse)
+	assertSeries(opts.c.vmselectGlobalRF, allowPartialResponse, mustReturnFullResponse)
+	assertSeries(opts.c.vmselectGroupGlobalRF, allowPartialResponse, mustReturnFullResponse)
 
 	// Stop groupRF-1 vmstorage nodes in first group.
 	//
@@ -1053,10 +1060,10 @@ func testGroupPartialResponse(tc *apptest.TestCase, opts *testGroupReplicationOp
 	// about the replication factor and therefore they must still be able to
 	// return full dataset.
 	opts.c.storageGroups[0].stopNodes(tc, opts.groupRF-1)
-	assertSeries(opts.c.vmselect, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGroupRF, mustReturnFullResponse)
-	assertSeries(opts.c.vmselectGlobalRF, mustReturnFullResponse)
-	assertSeries(opts.c.vmselectGroupGlobalRF, mustReturnFullResponse)
+	assertSeries(opts.c.vmselect, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupRF, allowPartialResponse, mustReturnFullResponse)
+	assertSeries(opts.c.vmselectGlobalRF, allowPartialResponse, mustReturnFullResponse)
+	assertSeries(opts.c.vmselectGroupGlobalRF, allowPartialResponse, mustReturnFullResponse)
 
 	// Stop groupRF-1 vmstorages in the remaining groups.
 	//
@@ -1066,10 +1073,10 @@ func testGroupPartialResponse(tc *apptest.TestCase, opts *testGroupReplicationOp
 	for g := 1; g < len(opts.c.storageGroups); g++ {
 		opts.c.storageGroups[g].stopNodes(tc, opts.groupRF-1)
 	}
-	assertSeries(opts.c.vmselect, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGroupRF, mustReturnFullResponse)
-	assertSeries(opts.c.vmselectGlobalRF, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGroupGlobalRF, mustReturnFullResponse)
+	assertSeries(opts.c.vmselect, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupRF, allowPartialResponse, mustReturnFullResponse)
+	assertSeries(opts.c.vmselectGlobalRF, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupGlobalRF, allowPartialResponse, mustReturnFullResponse)
 
 	// Stop one more vmstorage in the first group.
 	//
@@ -1077,10 +1084,10 @@ func testGroupPartialResponse(tc *apptest.TestCase, opts *testGroupReplicationOp
 	// because it is unaware of replication across groups. vmselectGroupGlobalRF
 	// will continue retuning full dataset.
 	opts.c.storageGroups[0].stopNodes(tc, 1)
-	assertSeries(opts.c.vmselect, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGroupRF, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGlobalRF, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGroupGlobalRF, mustReturnFullResponse)
+	assertSeries(opts.c.vmselect, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupRF, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGlobalRF, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupGlobalRF, allowPartialResponse, mustReturnFullResponse)
 
 	// Stop one more vmstoarge in remaining globarRF-1 groups.
 	//
@@ -1089,19 +1096,56 @@ func testGroupPartialResponse(tc *apptest.TestCase, opts *testGroupReplicationOp
 	for g := 1; g < opts.globalRF-1; g++ {
 		opts.c.storageGroups[g].stopNodes(tc, 1)
 	}
-	assertSeries(opts.c.vmselect, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGroupRF, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGlobalRF, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGroupGlobalRF, mustReturnFullResponse)
+	assertSeries(opts.c.vmselect, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupRF, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGlobalRF, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupGlobalRF, allowPartialResponse, mustReturnFullResponse)
 
 	// Stop one more vmstoarge in one more group.
 	//
 	// vmselectGroupGlobalRF must now return partial dataset.
 	opts.c.storageGroups[opts.globalRF].stopNodes(tc, 1)
-	assertSeries(opts.c.vmselect, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGroupRF, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGlobalRF, mustReturnPartialResponse)
-	assertSeries(opts.c.vmselectGroupGlobalRF, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselect, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupRF, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGlobalRF, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupGlobalRF, allowPartialResponse, mustReturnPartialResponse)
+
+	// Stop all the remaining vmstorage nodes except a single node.
+	//
+	// At this point vmselects still must be able to return partial response
+	// because at least one vmstorage node has successfully returned results.
+	n := len(opts.c.storageGroups[0].vmstorages)
+	opts.c.storageGroups[0].stopNodes(tc, n-1)
+	for g := 1; g < len(opts.c.storageGroups); g++ {
+		n := len(opts.c.storageGroups[g].vmstorages)
+		opts.c.storageGroups[g].stopNodes(tc, n)
+	}
+	assertSeries(opts.c.vmselect, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupRF, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGlobalRF, allowPartialResponse, mustReturnPartialResponse)
+	assertSeries(opts.c.vmselectGroupGlobalRF, allowPartialResponse, mustReturnPartialResponse)
+
+	mustReturnUnavailableError := &apptest.PrometheusAPIV1SeriesResponse{
+		Status:    "error",
+		ErrorType: "503",
+	}
+
+	// vmselects must return an error for the same request when partial
+	// responses are denied explicitly.
+	assertSeries(opts.c.vmselect, denyPartialResponse, mustReturnUnavailableError)
+	assertSeries(opts.c.vmselectGroupRF, denyPartialResponse, mustReturnUnavailableError)
+	assertSeries(opts.c.vmselectGlobalRF, denyPartialResponse, mustReturnUnavailableError)
+	assertSeries(opts.c.vmselectGroupGlobalRF, denyPartialResponse, mustReturnUnavailableError)
+
+	// Stop the last remaining vmstorage node.
+	//
+	// vmselects must return an error when there are no successful vmstorage
+	// responses.
+	opts.c.storageGroups[0].stopNodes(tc, 1)
+	assertSeries(opts.c.vmselect, allowPartialResponse, mustReturnUnavailableError)
+	assertSeries(opts.c.vmselectGroupRF, allowPartialResponse, mustReturnUnavailableError)
+	assertSeries(opts.c.vmselectGlobalRF, allowPartialResponse, mustReturnUnavailableError)
+	assertSeries(opts.c.vmselectGroupGlobalRF, allowPartialResponse, mustReturnUnavailableError)
 }
 
 // TestClusterReplication_PartialResponseMultitenant checks how vmselect handles some

apptest/tests/testdata/mimir-tsdb/anonymous/01JFJBS3YP1SHZ3PJQ6HK76EC3/meta.json

@@ -0,0 +1,51 @@
+{
+	"ulid": "01JFJBS3YP1SHZ3PJQ6HK76EC3",
+	"minTime": 1734709200000,
+	"maxTime": 1734709320000,
+	"stats": {
+		"numSamples": 400,
+		"numSeries": 100,
+		"numChunks": 100
+	},
+	"compaction": {
+		"level": 1,
+		"sources": [
+			"01JFJBS3YP1SHZ3PJQ6HK76EC3"
+		],
+		"parents": [
+			{
+				"ulid": "00000000000000000000000000",
+				"minTime": 0,
+				"maxTime": 0
+			}
+		],
+		"hints": [
+			"from-out-of-order"
+		]
+	},
+	"version": 1,
+	"out_of_order": false,
+	"thanos": {
+		"labels": {},
+		"downsample": {
+			"resolution": 0
+		},
+		"source": "receive",
+		"segment_files": [
+			"000001"
+		],
+		"files": [
+			{
+				"rel_path": "chunks/000001",
+				"size_bytes": 4808
+			},
+			{
+				"rel_path": "index",
+				"size_bytes": 55021
+			},
+			{
+				"rel_path": "meta.json"
+			}
+		]
+	}
+}

apptest/tests/vmctl_mimir_migration_test.go

@@ -0,0 +1,140 @@
+package tests
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp/cmpopts"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/apptest"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/fs"
+)
+
+const (
+	testMimirPath             = "testdata/mimir-tsdb"
+	expectedMimirResponseFile = "./testdata/mimir-tsdb/expected_response.json"
+)
+
+func TestSingleVmctlMimirProtocol(t *testing.T) {
+	fs.MustRemoveDir(t.Name())
+
+	tc := apptest.NewTestCase(t)
+	defer tc.Stop()
+
+	vmsingleDst := tc.MustStartDefaultVmsingle()
+	vmAddr := fmt.Sprintf("http://%s/", vmsingleDst.HTTPAddr())
+	dir, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("cannot get current working directory: %s", err)
+	}
+
+	path := fmt.Sprintf("fs://%s/%s", dir, testMimirPath)
+	vmctlFlags := []string{
+		`mimir`,
+		`--mimir-tenant-id=anonymous`,
+		`--mimir-filter-time-start=2024-12-01T00:00:00Z`,
+		`--mimir-filter-time-end=2024-12-31T23:59:59Z`,
+		`--mimir-custom-s3-endpoint=http://localhost:9000`,
+		`--mimir-path=` + path,
+		`--vm-addr=` + vmAddr,
+		`--disable-progress-bar=true`,
+		`--vm-concurrency=6`,
+		`--mimir-concurrency=6`,
+	}
+
+	testMimirProtocol(tc, vmsingleDst, vmctlFlags)
+}
+
+func TestClusterVmctlMimirProtocol(t *testing.T) {
+	fs.MustRemoveDir(t.Name())
+
+	tc := apptest.NewTestCase(t)
+	defer tc.Stop()
+
+	cluster := tc.MustStartDefaultCluster()
+	vmAddr := fmt.Sprintf("http://%s/", cluster.Vminsert.HTTPAddr())
+	dir, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("cannot get current working directory: %s", err)
+	}
+
+	path := fmt.Sprintf("fs://%s/%s", dir, testMimirPath)
+
+	vmctlFlags := []string{
+		`mimir`,
+		`--mimir-tenant-id=anonymous`,
+		`--mimir-filter-time-start=2024-12-01T00:00:00Z`,
+		`--mimir-filter-time-end=2024-12-31T23:59:59Z`,
+		`--mimir-custom-s3-endpoint=http://localhost:9000`,
+		`--mimir-path=` + path,
+		`--vm-addr=` + vmAddr,
+		`--disable-progress-bar=true`,
+		`--vm-concurrency=6`,
+		`--mimir-concurrency=6`,
+		`--vm-account-id=0`,
+	}
+
+	testMimirProtocol(tc, cluster, vmctlFlags)
+}
+
+func testMimirProtocol(tc *apptest.TestCase, sut apptest.PrometheusWriteQuerier, vmctlFlags []string) {
+	t := tc.T()
+	t.Helper()
+
+	cmpOpt := cmpopts.IgnoreFields(apptest.PrometheusAPIV1QueryResponse{}, "Status", "Data.ResultType")
+
+	// test for empty data request
+	got := sut.PrometheusAPIV1Query(t, `{__name__=~".*"}`, apptest.QueryOpts{
+		Step: "5m",
+		Time: "2025-06-02T17:14:00Z",
+	})
+
+	want := apptest.NewPrometheusAPIV1QueryResponse(t, `{"data":{"result":[]}}`)
+	if diff := cmp.Diff(want, got, cmpOpt); diff != "" {
+		t.Errorf("unexpected response (-want, +got):\n%s", diff)
+	}
+
+	tc.MustStartVmctl("vmctl", vmctlFlags)
+
+	sut.ForceFlush(t)
+
+	// open the expected series response file
+	file, err := os.Open(expectedMimirResponseFile)
+	if err != nil {
+		t.Fatalf("cannot open expected series response file: %s", err)
+	}
+	defer file.Close()
+
+	bytes, err := io.ReadAll(file)
+	if err != nil {
+		t.Fatalf("cannot read expected series response file: %s", err)
+	}
+
+	var wantResponse apptest.PrometheusAPIV1QueryResponse
+	if err := json.Unmarshal(bytes, &wantResponse); err != nil {
+		t.Fatalf("cannot unmarshal expected series response file: %s", err)
+	}
+	wantResponse.Sort()
+
+	tc.Assert(&apptest.AssertOptions{
+		// For cluster version, we need to wait longer for the metrics to be stored
+		Retries: 300,
+		Msg:     `unexpected metrics stored on vmsingle via the prometheus protocol`,
+		Got: func() any {
+			expected := sut.PrometheusAPIV1Export(t, `{__name__=~".*"}`, apptest.QueryOpts{
+				Start: "2024-12-01T15:31:10Z",
+				End:   "2024-12-31T15:32:20Z",
+			})
+			expected.Sort()
+			return expected.Data.Result
+		},
+		Want: wantResponse.Data.Result,
+		CmpOpts: []cmp.Option{
+			cmpopts.IgnoreFields(apptest.PrometheusAPIV1QueryResponse{}, "Status", "Data.ResultType"),
+		},
+	})
+}

dashboards/vm/vmalert.json

@@ -2804,10 +2804,10 @@
             "overrides": []
           },
           "gridPos": {
-            "h": 8,
+            "h": 7,
             "w": 12,
             "x": 0,
-            "y": 352
+            "y": 11
           },
           "id": 63,
           "options": {
@@ -2843,7 +2843,113 @@
           ],
           "title": "Restarts ($job)",
           "type": "timeseries"
-        }
+        },
+        {
+          "datasource": {
+            "type": "victoriametrics-metrics-datasource",
+            "uid": "$ds"
+          },
+          "description": "Group iteration reset can be caused by irregular delays during evaluation or by the system wall clock being moved backward.\nIf it is caused by host clock changes, vmalert could generate duplicate results for the group rules, since some evaluations could be repeated.\nCheck the host clock time synchronization configuration if this happens frequently.\n",
+          "fieldConfig": {
+            "defaults": {
+              "color": {
+                "mode": "palette-classic"
+              },
+              "custom": {
+                "axisBorderShow": false,
+                "axisCenteredZero": false,
+                "axisColorMode": "text",
+                "axisLabel": "",
+                "axisPlacement": "auto",
+                "barAlignment": 0,
+                "barWidthFactor": 0.6,
+                "drawStyle": "bars",
+                "fillOpacity": 10,
+                "gradientMode": "none",
+                "hideFrom": {
+                  "legend": false,
+                  "tooltip": false,
+                  "viz": false
+                },
+                "insertNulls": false,
+                "lineInterpolation": "linear",
+                "lineWidth": 1,
+                "pointSize": 5,
+                "scaleDistribution": {
+                  "type": "linear"
+                },
+                "showPoints": "never",
+                "showValues": false,
+                "spanNulls": false,
+                "stacking": {
+                  "group": "A",
+                  "mode": "none"
+                },
+                "thresholdsStyle": {
+                  "mode": "off"
+                }
+              },
+              "mappings": [],
+              "thresholds": {
+                "mode": "absolute",
+                "steps": [
+                  {
+                    "color": "green",
+                    "value": 0
+                  },
+                  {
+                    "color": "red",
+                    "value": 80
+                  }
+                ]
+              },
+              "unit": "short"
+            },
+            "overrides": []
+          },
+          "gridPos": {
+            "h": 7,
+            "w": 12,
+            "x": 12,
+            "y": 11
+          },
+          "id": 70,
+          "options": {
+            "legend": {
+              "calcs": [
+                "mean",
+                "lastNotNull",
+                "max"
+              ],
+              "displayMode": "table",
+              "placement": "bottom",
+              "showLegend": true
+            },
+            "tooltip": {
+              "hideZeros": false,
+              "mode": "multi",
+              "sort": "none"
+            }
+          },
+          "pluginVersion": "12.2.0",
+          "targets": [
+            {
+              "datasource": {
+                "type": "victoriametrics-metrics-datasource",
+                "uid": "$ds"
+              },
+              "editorMode": "code",
+              "exemplar": false,
+              "expr": "sum(increase(vmalert_iteration_reset_total{job=~\"$job\", instance=~\"$instance\"}[$__rate_interval])) by(job, group, file) > 0",
+              "interval": "1m",
+              "legendFormat": "({{job}}) {{group}}({{file}})",
+              "range": true,
+              "refId": "A"
+            }
+          ],
+          "title": "Group Iteration Reset ($instance)",
+          "type": "timeseries"
+        }        
       ],
       "title": "Troubleshooting",
       "type": "row"

dashboards/vmalert.json

@@ -2803,10 +2803,10 @@
             "overrides": []
           },
           "gridPos": {
-            "h": 8,
+            "h": 7,
             "w": 12,
             "x": 0,
-            "y": 352
+            "y": 11
           },
           "id": 63,
           "options": {
@@ -2842,7 +2842,113 @@
           ],
           "title": "Restarts ($job)",
           "type": "timeseries"
-        }
+        },
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "$ds"
+          },
+          "description": "Group iteration reset can be caused by irregular delays during evaluation or by the system wall clock being moved backward.\nIf it is caused by host clock changes, vmalert could generate duplicate results for the group rules, since some evaluations could be repeated.\nCheck the host clock time synchronization configuration if this happens frequently.\n",
+          "fieldConfig": {
+            "defaults": {
+              "color": {
+                "mode": "palette-classic"
+              },
+              "custom": {
+                "axisBorderShow": false,
+                "axisCenteredZero": false,
+                "axisColorMode": "text",
+                "axisLabel": "",
+                "axisPlacement": "auto",
+                "barAlignment": 0,
+                "barWidthFactor": 0.6,
+                "drawStyle": "bars",
+                "fillOpacity": 10,
+                "gradientMode": "none",
+                "hideFrom": {
+                  "legend": false,
+                  "tooltip": false,
+                  "viz": false
+                },
+                "insertNulls": false,
+                "lineInterpolation": "linear",
+                "lineWidth": 1,
+                "pointSize": 5,
+                "scaleDistribution": {
+                  "type": "linear"
+                },
+                "showPoints": "never",
+                "showValues": false,
+                "spanNulls": false,
+                "stacking": {
+                  "group": "A",
+                  "mode": "none"
+                },
+                "thresholdsStyle": {
+                  "mode": "off"
+                }
+              },
+              "mappings": [],
+              "thresholds": {
+                "mode": "absolute",
+                "steps": [
+                  {
+                    "color": "green",
+                    "value": 0
+                  },
+                  {
+                    "color": "red",
+                    "value": 80
+                  }
+                ]
+              },
+              "unit": "short"
+            },
+            "overrides": []
+          },
+          "gridPos": {
+            "h": 7,
+            "w": 12,
+            "x": 12,
+            "y": 11
+          },
+          "id": 70,
+          "options": {
+            "legend": {
+              "calcs": [
+                "mean",
+                "lastNotNull",
+                "max"
+              ],
+              "displayMode": "table",
+              "placement": "bottom",
+              "showLegend": true
+            },
+            "tooltip": {
+              "hideZeros": false,
+              "mode": "multi",
+              "sort": "none"
+            }
+          },
+          "pluginVersion": "12.2.0",
+          "targets": [
+            {
+              "datasource": {
+                "type": "prometheus",
+                "uid": "$ds"
+              },
+              "editorMode": "code",
+              "exemplar": false,
+              "expr": "sum(increase(vmalert_iteration_reset_total{job=~\"$job\", instance=~\"$instance\"}[$__rate_interval])) by(job, group, file) > 0",
+              "interval": "1m",
+              "legendFormat": "({{job}}) {{group}}({{file}})",
+              "range": true,
+              "refId": "A"
+            }
+          ],
+          "title": "Group Iteration Reset ($instance)",
+          "type": "timeseries"
+        }        
       ],
       "title": "Troubleshooting",
       "type": "row"

deployment/docker/rules/alerts-vmalert.yml

@@ -64,6 +64,18 @@ groups:
             group \"{{ $labels.group }}\". See https://docs.victoriametrics.com/victoriametrics/vmalert/#groups. 
             If rule expressions are taking longer than expected, please see https://docs.victoriametrics.com/victoriametrics/troubleshooting/#slow-queries."
 
+      - alert: GroupIterationReset
+        expr: increase(vmalert_iteration_reset_total[5m]) > 0
+        for: 5m
+        labels:
+          severity: warning
+        annotations:
+          summary: "Evaluation iteration for group {{ $labels.group }} in file {{ $labels.file }} is reset"
+          description: "Evaluation iteration for group \"{{ $labels.group }}\" in file \"{{ $labels.file }}\" is reset on vmalert instance {{ $labels.instance }}.
+            This can be caused by irregular delays during evaluation or by the system wall clock being moved backward. If it is caused by host clock changes, vmalert could
+            generate duplicate results for the group rules since some evaluations could be repeated. Check host clock time synchronization configurations if this happens frequently."
+
+
       - alert: RemoteWriteErrors
         expr: increase(vmalert_remotewrite_errors_total[5m]) > 0
         for: 15m
@@ -108,4 +120,3 @@ groups:
           summary: "vmalert instance {{ $labels.instance }} is failing to send notifications to Alertmanager"
           description: "vmalert instance {{ $labels.instance }} is failing to send alert notifications to \"{{ $labels.addr }}\".
             Check vmalert's logs for detailed error message."
-

deployment/docker/rules/alerts-vmanomaly.yml

@@ -40,7 +40,7 @@ groups:
         annotations:
           summary: "Metrics have not been seen from \"{{ $labels.job }}\"(\"{{ $labels.instance }}\") for {{ $value }} seconds"
           description: >
-           The missing metric may indicate that vmanomaly is not running or is inaccessible from vmagent or the remotewrite endpoint.
+            The missing metric may indicate that vmanomaly is not running or is inaccessible from vmagent or the remotewrite endpoint.
 
       - alert: ProcessNearFDLimits
         expr: (process_max_fds{job=~".*vmanomaly.*"} - process_open_fds{job=~".*vmanomaly.*"}) < 100

docs/victoriametrics/README.md

@@ -1136,6 +1136,8 @@ By default, the last point on the interval `[now - max_lookback ... now]` is scr
 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
 with scrape intervals exceeding `5m`.
 
+ VictoriaMetrics supports Prometheus v3.0 utf-8 content encoding with `Accept` header. If `Accept: allow-utf-8` HTTP header provided, `/federate` API response changes according to [Prometheus utf-8](https://prometheus.io/docs/guides/utf8/#querying) specification - `metric_name{tag="value"}` transforms into `{"metric_name","tag"="value"}`.
+
 ## Capacity planning
 
 VictoriaMetrics uses lower amounts of CPU, RAM and storage space on production workloads compared to competing solutions (Prometheus, Thanos, Cortex, TimescaleDB, InfluxDB, QuestDB, M3DB) according to [our case studies](https://docs.victoriametrics.com/victoriametrics/casestudies/).

docs/victoriametrics/changelog/CHANGELOG.md

@@ -26,7 +26,17 @@ See also [LTS releases](https://docs.victoriametrics.com/victoriametrics/lts-rel
 
 ## tip
 
+* FEATURE: [vmalert](https://docs.victoriametrics.com/victoriametrics/vmalert/): support `match[]=<label_selector>` query parameters in `/api/v1/rules` and `/api/v1/alerts` APIs to return only the rules that have configured labels satisfying the provided label selectors. See [11020](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/11020).
 * FEATURE: [vmagent](https://docs.victoriametrics.com/victoriametrics/vmagent/), [vmsingle](https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/) and `vminsert` in [VictoriaMetrics cluster](https://docs.victoriametrics.com/victoriametrics/cluster-victoriametrics/): add `-opentelemetry.promoteAllResourceAttributes` and `-opentelemetry.promoteScopeMetadata` command-line flags to allow managing label promotion for resource attributes and OTel scope metadata. See [OpenTelemetry](https://docs.victoriametrics.com/victoriametrics/integrations/opentelemetry/) docs and [#10931](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/10931).
+* FEATURE: [vmctl](https://docs.victoriametrics.com/vmctl/): add the ability to migrate data from Mimir object storage to VictoriaMetrics. See [#7717](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7717). 
+
+* BUGFIX: [vmalert](https://docs.victoriametrics.com/victoriametrics/vmalert/): fix the `Notifiers` page in web UI appearing blank despite the API returning notifier data correctly. See [#11035](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/11035).
+* BUGFIX: [vmalert](https://docs.victoriametrics.com/victoriametrics/vmalert/): reset the group evaluation timestamp if it exceeds the current host time. Previously, vmalert could use future timestamps for evaluations if the system clock was shifted backward. See [#10985](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/10985).
+* BUGFIX: [vmagent](https://docs.victoriametrics.com/victoriametrics/vmagent/) and [vmsingle](https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/): properly parse [Prometheus Native Histograms](https://prometheus.io/docs/specs/native_histograms/), previously Protobuf parser could produce unexpected `vmrange` labels. See [#11041](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/11041).
+* BUGFIX: [MetricsQL](https://docs.victoriametrics.com/victoriametrics/metricsql/): `integrate()` no longer extrapolates the last sample's value past the end of the time series. Previously, querying `integrate(metric[1h])` at a timestamp where the series had already ended would keep accruing area as if the last value continued indefinitely, producing values much larger than the true integral. See [#9474](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/9474). Thanks to @wtfashwin for contribution.
+* BUGFIX: `vmselect` in [VictoriaMetrics cluster](https://docs.victoriametrics.com/victoriametrics/cluster-victoriametrics/): avoid returning HTTP 503 for queries with partial results when a storage group is unavailable and `-search.denyPartialResponse` is disabled.
+* BUGFIX: [vmsingle](https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/) and `vmselect` in [VictoriaMetrics cluster](https://docs.victoriametrics.com/victoriametrics/cluster-victoriametrics/): properly escape `utf-8` label names for [/federate](https://docs.victoriametrics.com/victoriametrics/#federation) API requests. See [#10968](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/10968).
+* BUGFIX: [vmui](https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/#vmui): persist the `Disable deduplication` toggle under its own local storage key. Before this fix, the toggle state was lost after reload and could overwrite the `Compact view` table setting. See [#11004](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/11004). Thanks to @immanuwell for the contribution.
 
 ## [v1.144.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.144.0)
 

docs/victoriametrics/changelog/CHANGELOG_2024.md

@@ -173,7 +173,7 @@ Released at 2024-10-02
 
 It is recommended upgrading to [v1.107.0](https://docs.victoriametrics.com/victoriametrics/changelog/#v11070) because [v1.104.0](https://docs.victoriametrics.com/victoriametrics/changelog/#v11040) contains a bug, which can lead to runtime panic at `vmselect` component. See this [issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7549) for details.
 
-**Update note 1: `*.passwordFile` and similar flags are trimming trailing whitespaces at the end of content. If authorization check performed with `*.passwordFile` content, make sure to update authorization settings to not include trailing whitespaces before the upgrade. In case of [operator](https://docs.victoriametrics.com/operator/) managed installations, make sure to update operator version to [v0.48.*](https://docs.victoriametrics.com/operator/changelog/#v0480---25-sep-2024). See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6986) for the details. This change reverts behavior introduced at [v1.102.0-rc2](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.102.0-rc2) release**
+**Update note 1: `*.passwordFile` and similar flags are trimming trailing whitespaces at the end of content. If authorization check performed with `*.passwordFile` content, make sure to update authorization settings to not include trailing whitespaces before the upgrade. In case of [operator](https://docs.victoriametrics.com/operator/) managed installations, make sure to update operator version to [v0.48.*](https://docs.victoriametrics.com/operator/changelog/#v0480). See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6986) for the details. This change reverts behavior introduced at [v1.102.0-rc2](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.102.0-rc2) release**
 
 * SECURITY: upgrade Go builder from Go1.23.0 to Go1.23.1. See the list of issues addressed in [Go1.23.1](https://github.com/golang/go/issues?q=milestone%3AGo1.23.1+label%3ACherryPickApproved).
 * SECURITY: upgrade base docker image (Alpine) from 3.20.2 to 3.20.3. See [alpine 3.20.3 release notes](https://alpinelinux.org/posts/Alpine-3.17.10-3.18.9-3.19.4-3.20.3-released.html).

docs/victoriametrics/vmagent_common_flags.md

@@ -502,7 +502,7 @@ See the docs at https://docs.victoriametrics.com/victoriametrics/vmagent/ .
      Supports array of values separated by comma or specified via multiple flags.
      Empty values are set to default value.
   -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 (default 100)
+     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. See also -remoteWrite.significantFigures (default 100)
      Supports array of values separated by comma or specified via multiple flags.
      Empty values are set to default value.
   -remoteWrite.sendTimeout array

docs/victoriametrics/vmalert.md

@@ -801,17 +801,15 @@ Please refer to the [VictoriaMetrics Cloud documentation](https://docs.victoriam
 `vmalert` runs a web-server (`-httpListenAddr`) for serving metrics and alerts endpoints:
 
 * `http://<vmalert-addr>` - UI;
-* `http://<vmalert-addr>/api/v1/rules` - list of all loaded groups and rules. Supports `search`, `group_limit`, and `page_num` parameters, as well as additional [filtering](https://prometheus.io/docs/prometheus/latest/querying/api/#rules);
-* `http://<vmalert-addr>/api/v1/alerts` - list of all active alerts;
-* `http://<vmalert-addr>/api/v1/notifiers` - list all available notifiers;
-* `http://<vmalert-addr>/vmalert/api/v1/alert?group_id=<group_id>&alert_id=<alert_id>` - get alert status in JSON format.
-* `http://<vmalert-addr>/vmalert/api/v1/rule?group_id=<group_id>&rule_id=<rule_id>` - get rule status in JSON format.
-* `http://<vmalert-addr>/vmalert/api/v1/group?group_id=<group_id>` - get group status in JSON format.
-Used as alert source in AlertManager.
-* `http://<vmalert-addr>/vmalert/alert?group_id=<group_id>&alert_id=<alert_id>` - get alert status in web UI.
-* `http://<vmalert-addr>/vmalert/rule?group_id=<group_id>&rule_id=<rule_id>` - get rule status in web UI.
-* `http://<vmalert-addr>/vmalert/api/v1/rule?group_id=<group_id>&alert_id=<alert_id>` - get rule status in JSON format.
-* `http://<vmalert-addr>/metrics` - application metrics.
+* `http://<vmalert-addr>/api/v1/rules` - returns a list of all loaded groups and rules. Supports the `datasource_type`, `search`, `group_limit`, and `page_num` parameters, as well as additional [filtering](https://prometheus.io/docs/prometheus/latest/querying/api/#rules);
+* `http://<vmalert-addr>/api/v1/alerts` - returns a list of all active alerts. Supports the `datasource_type`, `rule_group[]`, `file[]` and `match[]`(applied on templated alert labels) query parameters;
+* `http://<vmalert-addr>/api/v1/notifiers` - returns a list of all available notifiers;
+* `http://<vmalert-addr>/vmalert/api/v1/alert?group_id=<group_id>&alert_id=<alert_id>` - returns the alert status in JSON format;
+* `http://<vmalert-addr>/vmalert/api/v1/rule?group_id=<group_id>&rule_id=<rule_id>` - returns the rule status in JSON format;
+* `http://<vmalert-addr>/vmalert/api/v1/group?group_id=<group_id>` - returns the group status in JSON format. Used as the alert source in AlertManager;
+* `http://<vmalert-addr>/vmalert/alert?group_id=<group_id>&alert_id=<alert_id>` - displays the alert status in the web UI;
+* `http://<vmalert-addr>/vmalert/rule?group_id=<group_id>&rule_id=<rule_id>` - displays the rule status in the web UI;
+* `http://<vmalert-addr>/metrics` - application metrics endpoint;
 * `http://<vmalert-addr>/-/reload` - hot configuration reload.
 
 `vmalert` web UI can be accessed from [single-node version of VictoriaMetrics](https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/)

docs/victoriametrics/vmctl/mimir.md

@@ -73,4 +73,66 @@ ou can define it via the flag `--remote-read-headers=X-Scope-OrgID:demo`.
 
 See [remote-read mode](https://docs.victoriametrics.com/victoriametrics/vmctl/remoteread/) for more details.
 
-See also general [vmctl migration tips](https://docs.victoriametrics.com/victoriametrics/vmctl/#migration-tips).
+See also general [vmctl migration tips](https://docs.victoriametrics.com/victoriametrics/vmctl/#migration-tips).
+
+### Read data from the remote storage like S3, GCS, Azure etc.
+
+If you have data stored in remote storage like S3, GCS, Azure etc. you can use `vmctl` in `mimir` mode to read data from 
+the remote storage and import it into VictoriaMetrics. In this mode `vmctl` reads data from the remote storage or file system
+and checks index file, define needed blocks to be processed. After it downloads blocks by defined filters and 
+use Prometheus converter to read and sent data to VictoriaMetrics.
+
+The following example shows how to read data from the file system and import it into VictoriaMetrics:
+
+```sh
+./vmctl mimir --mimir-path="fs:///mimir/test_data/mimir-tsdb" \                                               ? ? orbstack 
+  --mimir-tenant-id=anonymous \
+  --mimir-filter-time-start=2024-12-01T00:00:00 \
+  --mimir-filter-time-end=2024-12-18T23:59:59 \
+  --mimir-creds-file-path=creads \
+  --vm-concurrency=6 \
+  --mimir-concurrency=6 \
+  --vm-addr=http://localhost:8428/
+```
+This approach is useful when you have data stored on the local file system or you have a mounted volume, 
+download the data from the remote storage etc.
+
+The following example shows how to read data from the remote storage and import it into VictoriaMetrics:
+
+```sh
+./vmctl mimir --mimir-path="s3:///mimir-tsdb/anonymous" \
+  --mimir-filter-time-start=2024-12-01T00:00:00 \
+  --mimir-filter-time-end=2024-12-17T23:59:59 \
+  --mimir-creds-file-path=creads \
+  --mimir-custom-s3-endpoint='http://localhost:9000' \
+  --vm-concurrency=6 \
+  --mimir-concurrency=6 \
+  --vm-addr=http://localhost:8428/
+```
+
+In the example above we are used `--mimir-custom-s3-endpoint` flag to specify the custom S3 endpoint if it is needed.
+
+When the process finishes, you will see the following:
+
+```sh
+2025/01/18 13:01:59 Fetching blocks from remote storage
+Found 204 blocks to import. Continue? [Y/n] y
+VM worker 0:? 1589405 samples/s                                                                                                                                                                                     
+VM worker 1:? 1911834 samples/s                                                                                                                                                                                     
+VM worker 2:? 1849187 samples/s                                                                                                                                                                                     
+VM worker 3:? 1648820 samples/s                                                                                                                                                                                     
+VM worker 4:? 1539212 samples/s                                                                                                                                                                                     
+VM worker 5:? 1411485 samples/s                                                                                                                                                                                     
+Processing blocks: 204 / 204 [?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????] 100.00%
+2025/01/18 13:02:18 Import finished!
+2025/01/18 13:02:18 VictoriaMetrics importer stats:
+  idle duration: 18.485875611s;
+  time spent while importing: 16.40543875s;
+  total samples: 177961995;
+  samples/s: 10847743.71;
+  total bytes: 4.1 GB;
+  bytes/s: 248.2 MB;
+  import requests: 893;
+  import requests retries: 0;
+2025/01/18 13:02:18 Total time: 18.867547083s
+```

docs/victoriametrics/vmctl/vmctl_influx_flags.md

@@ -56,7 +56,7 @@ OPTIONS:
    --vm-compress                                      Whether to apply gzip compression to import requests (default: true)
    --vm-batch-size value                              How many samples importer collects before sending the import request to VM (default: 200000)
    --vm-significant-figures value                     The number of significant figures to leave in metric values before importing. See https://en.wikipedia.org/wiki/Significant_figures. Zero value saves all the significant figures. This option may be used for increasing on-disk compression level for the stored metrics. See also --vm-round-digits option (default: 0)
-   --vm-round-digits value                            Round metric values to the given number of decimal digits after the point. This option may be used for increasing on-disk compression level for the stored metrics (default: 100)
+   --vm-round-digits value                            Round metric values to the given number of decimal digits after the point. This option may be used for increasing on-disk compression level for the stored metrics. See also --vm-significant-figures option (default: 100)
    --vm-extra-label value [ --vm-extra-label value ]  Extra labels, that will be added to imported timeseries. In case of collision, label value defined by flag will have priority. Flag can be set multiple times, to add few additional labels.
    --vm-rate-limit value                              Optional data transfer rate limit in bytes per second.
       By default, the rate limit is disabled. It can be useful for limiting load on configured via '--vm-addr' destination. (default: 0)

docs/victoriametrics/vmctl/vmctl_opentsdb_flags.md

@@ -51,7 +51,7 @@ OPTIONS:
    --vm-compress                                      Whether to apply gzip compression to import requests (default: true)
    --vm-batch-size value                              How many samples importer collects before sending the import request to VM (default: 200000)
    --vm-significant-figures value                     The number of significant figures to leave in metric values before importing. See https://en.wikipedia.org/wiki/Significant_figures. Zero value saves all the significant figures. This option may be used for increasing on-disk compression level for the stored metrics. See also --vm-round-digits option (default: 0)
-   --vm-round-digits value                            Round metric values to the given number of decimal digits after the point. This option may be used for increasing on-disk compression level for the stored metrics (default: 100)
+   --vm-round-digits value                            Round metric values to the given number of decimal digits after the point. This option may be used for increasing on-disk compression level for the stored metrics. See also --vm-significant-figures option (default: 100)
    --vm-extra-label value [ --vm-extra-label value ]  Extra labels, that will be added to imported timeseries. In case of collision, label value defined by flag will have priority. Flag can be set multiple times, to add few additional labels.
    --vm-rate-limit value                              Optional data transfer rate limit in bytes per second.
       By default, the rate limit is disabled. It can be useful for limiting load on configured via '--vm-addr' destination. (default: 0)

docs/victoriametrics/vmctl/vmctl_prometheus_flags.md

@@ -44,7 +44,7 @@ OPTIONS:
    --vm-compress                                      Whether to apply gzip compression to import requests (default: true)
    --vm-batch-size value                              How many samples importer collects before sending the import request to VM (default: 200000)
    --vm-significant-figures value                     The number of significant figures to leave in metric values before importing. See https://en.wikipedia.org/wiki/Significant_figures. Zero value saves all the significant figures. This option may be used for increasing on-disk compression level for the stored metrics. See also --vm-round-digits option (default: 0)
-   --vm-round-digits value                            Round metric values to the given number of decimal digits after the point. This option may be used for increasing on-disk compression level for the stored metrics (default: 100)
+   --vm-round-digits value                            Round metric values to the given number of decimal digits after the point. This option may be used for increasing on-disk compression level for the stored metrics. See also --vm-significant-figures option (default: 100)
    --vm-extra-label value [ --vm-extra-label value ]  Extra labels, that will be added to imported timeseries. In case of collision, label value defined by flag will have priority. Flag can be set multiple times, to add few additional labels.
    --vm-rate-limit value                              Optional data transfer rate limit in bytes per second.
       By default, the rate limit is disabled. It can be useful for limiting load on configured via '--vm-addr' destination. (default: 0)

docs/victoriametrics/vmctl/vmctl_remote-read_flags.md

@@ -59,7 +59,7 @@ OPTIONS:
    --vm-compress                                      Whether to apply gzip compression to import requests (default: true)
    --vm-batch-size value                              How many samples importer collects before sending the import request to VM (default: 200000)
    --vm-significant-figures value                     The number of significant figures to leave in metric values before importing. See https://en.wikipedia.org/wiki/Significant_figures. Zero value saves all the significant figures. This option may be used for increasing on-disk compression level for the stored metrics. See also --vm-round-digits option (default: 0)
-   --vm-round-digits value                            Round metric values to the given number of decimal digits after the point. This option may be used for increasing on-disk compression level for the stored metrics (default: 100)
+   --vm-round-digits value                            Round metric values to the given number of decimal digits after the point. This option may be used for increasing on-disk compression level for the stored metrics. See also --vm-significant-figures option (default: 100)
    --vm-extra-label value [ --vm-extra-label value ]  Extra labels, that will be added to imported timeseries. In case of collision, label value defined by flag will have priority. Flag can be set multiple times, to add few additional labels.
    --vm-rate-limit value                              Optional data transfer rate limit in bytes per second.
       By default, the rate limit is disabled. It can be useful for limiting load on configured via '--vm-addr' destination. (default: 0)

lib/prompb/write_request_unmarshaler.go

@@ -398,6 +398,10 @@ func (nhctx *nativeHistogramContext) appendTimeSeries(tss []TimeSeries, baseLabe
 	if baseName == "" {
 		return tss, labelsPool, samplesPool
 	}
+	originName := *nameValueP
+	defer func() {
+		*nameValueP = originName
+	}()
 
 	*nameValueP = fb.formatName(baseName, "_count")
 	tss, labelsPool, samplesPool = appendHistogramSeries(tss, labelsPool, samplesPool, baseLabels, "", tsMillis, count)
@@ -550,9 +554,11 @@ func (nhctx *nativeHistogramContext) reset() {
 	nhctx.zeroCountInt = 0
 	nhctx.zeroCountFloat = 0
 	nhctx.timestamp = 0
+	clear(nhctx.negativeSpans)
 	nhctx.negativeSpans = nhctx.negativeSpans[:0]
 	nhctx.negativeDeltas = nhctx.negativeDeltas[:0]
 	nhctx.negativeCounts = nhctx.negativeCounts[:0]
+	clear(nhctx.positiveSpans)
 	nhctx.positiveSpans = nhctx.positiveSpans[:0]
 	nhctx.positiveDeltas = nhctx.positiveDeltas[:0]
 	nhctx.positiveCounts = nhctx.positiveCounts[:0]

lib/prompb/write_request_unmarshaler_test.go

@@ -3,8 +3,9 @@ package prompb
 import (
 	"encoding/binary"
 	"math"
-	"reflect"
 	"testing"
+
+	"github.com/google/go-cmp/cmp"
 )
 
 func TestUnmarshalTimeSeries(t *testing.T) {
@@ -18,8 +19,8 @@ func TestUnmarshalTimeSeries(t *testing.T) {
 		if err != nil {
 			t.Fatalf("unexpected error: %s", err)
 		}
-		if !reflect.DeepEqual(tss, wantTSS) {
-			t.Fatalf("unexpected result\ngot:\n%v\nwant:\n%v", tss, wantTSS)
+		if diff := cmp.Diff(wantTSS, tss); len(diff) > 0 {
+			t.Fatalf("unexpected timeseries (-want, +got):\n%s", diff)
 		}
 	}
 
@@ -197,6 +198,93 @@ func TestUnmarshalTimeSeries(t *testing.T) {
 			},
 		})
 	}
+
+	{
+		// verify histogram fields are correctly reused
+		nativeHistogramC := nativeHistogramContext{
+			countInt:         0,
+			isCountFloat:     true,
+			countFloat:       2.5,
+			sum:              1.0,
+			schema:           1,
+			zeroThreshold:    0.00001,
+			isZeroCountFloat: true,
+			zeroCountFloat:   0.5,
+			timestamp:        3000,
+			positiveSpans:    []bucketSpan{{offset: 1, length: 2}},
+			positiveCounts:   []float64{1.5, 1.0},
+			negativeSpans:    []bucketSpan{{offset: 0, length: 1}},
+		}
+		nativeHistogramC2 := nativeHistogramContext{
+			countInt:         0,
+			isCountFloat:     true,
+			countFloat:       0,
+			sum:              1.0,
+			schema:           1,
+			zeroThreshold:    0.00001,
+			isZeroCountFloat: true,
+			zeroCountFloat:   0.5,
+			timestamp:        4000,
+			positiveSpans:    []bucketSpan{{offset: 0, length: 2}},
+			positiveCounts:   []float64{1.5, 1.0},
+			negativeSpans:    []bucketSpan{{offset: 0, length: 1}},
+			negativeCounts:   []float64{1.5, 0},
+		}
+		hd1 := encodeHistogram(nativeHistogramC)
+		hd2 := encodeHistogram(nativeHistogramC2)
+
+		src := encodeTimeSeries(
+			[]Label{{Name: "__name__", Value: "rpc_latency_seconds"}},
+			nil,
+			[][]byte{hd1, hd2},
+		)
+		f(src, []TimeSeries{
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_count"}},
+				Samples: []Sample{{Value: 2.5, Timestamp: 3000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_sum"}},
+				Samples: []Sample{{Value: 1.0, Timestamp: 3000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_bucket"}, {Name: "vmrange", Value: appendVmrangeHelper(-0.00001, 0.00001)}},
+				Samples: []Sample{{Value: 0.5, Timestamp: 3000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_bucket"}, {Name: "vmrange", Value: appendVmrangeHelper(1, 1.414)}},
+				Samples: []Sample{{Value: 1.5, Timestamp: 3000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_bucket"}, {Name: "vmrange", Value: appendVmrangeHelper(1.414, 2.0)}},
+				Samples: []Sample{{Value: 1.0, Timestamp: 3000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_count"}},
+				Samples: []Sample{{Value: 0, Timestamp: 4000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_sum"}},
+				Samples: []Sample{{Value: 1.0, Timestamp: 4000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_bucket"}, {Name: "vmrange", Value: appendVmrangeHelper(-0.00001, 0.00001)}},
+				Samples: []Sample{{Value: 0.5, Timestamp: 4000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_bucket"}, {Name: "vmrange", Value: appendVmrangeHelper(0.7071, 1)}},
+				Samples: []Sample{{Value: 1.5, Timestamp: 4000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_bucket"}, {Name: "vmrange", Value: appendVmrangeHelper(1, 1.414)}},
+				Samples: []Sample{{Value: 1.0, Timestamp: 4000}},
+			},
+			{
+				Labels:  []Label{{Name: "__name__", Value: "rpc_latency_seconds_bucket"}, {Name: "vmrange", Value: appendVmrangeHelper(-1, -0.7071)}},
+				Samples: []Sample{{Value: 1.5, Timestamp: 4000}},
+			},
+		})
+	}
 }
 
 func encodeTimeSeries(labels []Label, samples []Sample, histograms [][]byte) []byte {

lib/vmselectapi/server.go

@@ -76,6 +76,15 @@ type Server struct {
 
 // Limits contains various limits for Server.
 type Limits struct {
+	// MaxLabelNames is the maximum label names, which may be returned from labelNames request.
+	MaxLabelNames int
+
+	// MaxLabelValues is the maximum label values, which may be returned from labelValues request.
+	MaxLabelValues int
+
+	// MaxTagValueSuffixes is the maximum number of entries, which can be returned from tagValueSuffixes request.
+	MaxTagValueSuffixes int
+
 	// MaxConcurrentRequests is the maximum number of concurrent requests a server can process.
 	//
 	// The remaining requests wait for up to MaxQueueDuration for their execution.
@@ -674,6 +683,9 @@ func (s *Server) processLabelNames(ctx *vmselectRequestCtx) error {
 	if err != nil {
 		return fmt.Errorf("cannot read maxLabelNames: %w", err)
 	}
+	if maxLabelNames <= 0 || maxLabelNames > s.limits.MaxLabelNames {
+		maxLabelNames = s.limits.MaxLabelNames
+	}
 
 	if err := s.beginConcurrentRequest(ctx); err != nil {
 		return ctx.writeErrorMessage(err)
@@ -725,6 +737,9 @@ func (s *Server) processLabelValues(ctx *vmselectRequestCtx) error {
 	if err != nil {
 		return fmt.Errorf("cannot read maxLabelValues: %w", err)
 	}
+	if maxLabelValues <= 0 || maxLabelValues > s.limits.MaxLabelValues {
+		maxLabelValues = s.limits.MaxLabelValues
+	}
 
 	if err := s.beginConcurrentRequest(ctx); err != nil {
 		return ctx.writeErrorMessage(err)
@@ -787,6 +802,9 @@ func (s *Server) processTagValueSuffixes(ctx *vmselectRequestCtx) error {
 	if err != nil {
 		return fmt.Errorf("cannot read maxTagValueSuffixes: %w", err)
 	}
+	if maxSuffixes <= 0 || maxSuffixes > s.limits.MaxTagValueSuffixes {
+		maxSuffixes = s.limits.MaxTagValueSuffixes
+	}
 
 	if err := s.beginConcurrentRequest(ctx); err != nil {
 		return ctx.writeErrorMessage(err)
@@ -799,6 +817,14 @@ func (s *Server) processTagValueSuffixes(ctx *vmselectRequestCtx) error {
 		return ctx.writeErrorMessage(err)
 	}
 
+	if len(suffixes) >= s.limits.MaxTagValueSuffixes {
+		err := fmt.Errorf("more than %d tag value suffixes found "+
+			"for tagKey=%q, tagValuePrefix=%q, delimiter=%c on time range %s; "+
+			"either narrow down the query or increase -search.max* command-line flag value; see https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/#resource-usage-limits",
+			s.limits.MaxTagValueSuffixes, tagKey, tagValuePrefix, delimiter, tr.String())
+		return ctx.writeErrorMessage(err)
+	}
+
 	// Send an empty error message to vmselect.
 	if err := ctx.writeString(""); err != nil {
 		return fmt.Errorf("cannot send empty error message: %w", err)