address review comments and make linter happy

Signed-off-by: f41gh7 <nik@victoriametrics.com>

app/vmselect/clusternative/vmselect.go

@@ -117,9 +117,9 @@ func (api *vmstorageAPI) ResetMetricNamesUsageStats(qt *querytracer.Tracer, dead
 	return netstorage.ResetMetricNamesStats(qt, dl)
 }
 
-func (api *vmstorageAPI) GetMetricNamesUsageStats(qt *querytracer.Tracer, tt *storage.TenantToken, le, limit int, matchPattern string, deadline uint64) (storage.MetricNamesStatsResponse, error) {
+func (api *vmstorageAPI) GetMetricNamesUsageStats(qt *querytracer.Tracer, statsQuery storage.MetricNamesStatsQuery, deadline uint64) (storage.MetricNamesStatsResponse, error) {
 	dl := searchutil.DeadlineFromTimestamp(deadline)
-	return netstorage.GetMetricNamesStats(qt, tt, le, limit, matchPattern, dl)
+	return netstorage.GetMetricNamesStats(qt, statsQuery, dl)
 }
 
 // blockIterator implements vmselectapi.BlockIterator

app/vmselect/netstorage/netstorage.go

@@ -2,6 +2,7 @@ package netstorage
 
 import (
 	"container/heap"
+	"encoding/json"
 	"errors"
 	"flag"
 	"fmt"
@@ -3031,12 +3032,6 @@ func writeUint64(bc *handshake.BufferedConn, n uint64) error {
 	return err
 }
 
-func writeInt64(bc *handshake.BufferedConn, n int64) error {
-	sizeBuf := encoding.MarshalInt64(nil, n)
-	_, err := bc.Write(sizeBuf)
-	return err
-}
-
 func writeBool(bc *handshake.BufferedConn, b bool) error {
 	var buf [1]byte
 	if b {
@@ -3337,14 +3332,14 @@ func metricNameTenantToTags(mn *storage.MetricName) {
 }
 
 // GetMetricNamesStats returns metric names usage statistics for the given params
-func GetMetricNamesStats(qt *querytracer.Tracer, tt *storage.TenantToken, limit, le int, matchPattern string, deadline searchutil.Deadline) (storage.MetricNamesStatsResponse, error) {
+func GetMetricNamesStats(qt *querytracer.Tracer, statsQuery storage.MetricNamesStatsQuery, deadline searchutil.Deadline) (storage.MetricNamesStatsResponse, error) {
 	type nodeResult struct {
 		resp storage.MetricNamesStatsResponse
 		err  error
 	}
 	sns := getStorageNodes()
 	snr := startStorageNodesRequest(qt, sns, true, func(qt *querytracer.Tracer, _ uint, sn *storageNode) any {
-		resp, err := sn.processGetMetricNamesStats(qt, tt, limit, le, matchPattern, deadline)
+		resp, err := sn.processGetMetricNamesStats(qt, statsQuery, deadline)
 		return nodeResult{resp: resp, err: err}
 	})
 	var mu sync.Mutex
@@ -3365,45 +3360,31 @@ func GetMetricNamesStats(qt *querytracer.Tracer, tt *storage.TenantToken, limit,
 	return mnuss, nil
 }
 
-func (sn *storageNode) processGetMetricNamesStats(qt *querytracer.Tracer, tt *storage.TenantToken, limit, le int, matchPattern string, deadline searchutil.Deadline) (storage.MetricNamesStatsResponse, error) {
+func (sn *storageNode) processGetMetricNamesStats(qt *querytracer.Tracer, statsQuery storage.MetricNamesStatsQuery, deadline searchutil.Deadline) (storage.MetricNamesStatsResponse, error) {
 	var result storage.MetricNamesStatsResponse
 	f := func(bc *handshake.BufferedConn) error {
-		bcResult, err := processGetMetricNamesUsageStatsOnConn(bc, tt, limit, le, matchPattern)
+		bcResult, err := processGetMetricNamesUsageStatsOnConn(bc, statsQuery)
 		if err != nil {
 			return err
 		}
 		result = bcResult
 		return nil
 	}
-	if err := sn.execOnConnWithPossibleRetry(qt, "metricNamesUsageStats_v1", f, deadline); err != nil {
+	if err := sn.execOnConnWithPossibleRetry(qt, "metricNamesUsageStats_v2", f, deadline); err != nil {
 		return result, err
 	}
 	return result, nil
 }
 
-func processGetMetricNamesUsageStatsOnConn(bc *handshake.BufferedConn, tt *storage.TenantToken, limit, le int, matchPattern string) (storage.MetricNamesStatsResponse, error) {
+func processGetMetricNamesUsageStatsOnConn(bc *handshake.BufferedConn, statsQuery storage.MetricNamesStatsQuery) (storage.MetricNamesStatsResponse, error) {
 	var result storage.MetricNamesStatsResponse
-	hasTenantToken := tt != nil
-	if err := writeBool(bc, hasTenantToken); err != nil {
-		return result, fmt.Errorf("cannot write hasTenantToken: %w", err)
+
+	data, err := json.Marshal(statsQuery)
+	if err != nil {
+		return result, fmt.Errorf("cannot marshal MetricNamesStatsQuery: %w", err)
 	}
-	// conditionally write tenant token
-	if hasTenantToken {
-		if err := writeUint32(bc, tt.AccountID); err != nil {
-			return result, fmt.Errorf("cannot write AccountID: %w", err)
-		}
-		if err := writeUint32(bc, tt.ProjectID); err != nil {
-			return result, fmt.Errorf("cannot write ProjectID: %w", err)
-		}
-	}
-	if err := writeLimit(bc, limit); err != nil {
-		return result, fmt.Errorf("cannot write limit: %w", err)
-	}
-	if err := writeInt64(bc, int64(le)); err != nil {
-		return result, fmt.Errorf("cannot write le: %w", err)
-	}
-	if err := writeBytes(bc, []byte(matchPattern)); err != nil {
-		return result, fmt.Errorf("cannot write matchPattern: %w", err)
+	if err := writeBytes(bc, data); err != nil {
+		return result, fmt.Errorf("cannot write MetricNamesStatsQuery: %w", err)
 	}
 	if err := bc.Flush(); err != nil {
 		return result, fmt.Errorf("cannot flush write: %w", err)

app/vmselect/stats/stats.go

@@ -45,7 +45,18 @@ func MetricNamesStatsHandler(startTime time.Time, at *auth.Token, qt *querytrace
 			ProjectID: at.ProjectID,
 		}
 	}
-	stats, err := netstorage.GetMetricNamesStats(qt, tt, limit, le, matchPattern, deadline)
+	matchNames := r.Form["match_names"]
+	statsQuery := storage.MetricNamesStatsQuery{
+		TenantToken:  tt,
+		Limit:        limit,
+		Le:           le,
+		MatchNames:   matchNames,
+		MatchPattern: matchPattern,
+	}
+	if limit > 0 && len(matchNames) > limit {
+		return fmt.Errorf("match_names len=%d cannot exceed limit=%d", len(matchNames), limit)
+	}
+	stats, err := netstorage.GetMetricNamesStats(qt, statsQuery, deadline)
 	if err != nil {
 		return err
 	}

app/vmstorage/servers/vmselect.go

@@ -195,8 +195,8 @@ func (api *vmstorageAPI) RegisterMetricNames(qt *querytracer.Tracer, mrs []stora
 	return nil
 }
 
-func (api *vmstorageAPI) GetMetricNamesUsageStats(qt *querytracer.Tracer, tt *storage.TenantToken, limit, le int, matchPattern string, _ uint64) (storage.MetricNamesStatsResponse, error) {
-	return api.s.GetMetricNamesStats(qt, tt, limit, le, matchPattern), nil
+func (api *vmstorageAPI) GetMetricNamesUsageStats(qt *querytracer.Tracer, statsQuery storage.MetricNamesStatsQuery, _ uint64) (storage.MetricNamesStatsResponse, error) {
+	return api.s.GetMetricNamesStats(qt, statsQuery), nil
 }
 
 func (api *vmstorageAPI) ResetMetricNamesUsageStats(qt *querytracer.Tracer, _ uint64) error {

apptest/tests/metric_names_stats_test.go

@@ -122,7 +122,7 @@ func TestClusterMetricNamesStats(t *testing.T) {
 		fmt.Sprintf("-storageNode=%s,%s", vmstorage1.VmselectAddr(), vmstorage2.VmselectAddr()),
 	})
 	// verify empty stats
-	resp := vmselect.MetricNamesStats(t, "", "", "", apptest.QueryOpts{Tenant: "0:0"})
+	resp := vmselect.MetricNamesStats(t, "", "", "", nil, apptest.QueryOpts{Tenant: "0:0"})
 	if len(resp.Records) != 0 {
 		t.Fatalf("unexpected resp Records: %d, want: %d", len(resp.Records), 0)
 	}
@@ -155,7 +155,7 @@ func TestClusterMetricNamesStats(t *testing.T) {
 				{MetricName: "metric_name_3"},
 			},
 		}
-		gotStats := vmselect.MetricNamesStats(t, "", "", "", apptest.QueryOpts{Tenant: tenantID})
+		gotStats := vmselect.MetricNamesStats(t, "", "", "", nil, apptest.QueryOpts{Tenant: tenantID})
 		if diff := cmp.Diff(expected, gotStats); diff != "" {
 			t.Errorf("unexpected response (-want, +got):\n%s", diff)
 		}
@@ -172,7 +172,17 @@ func TestClusterMetricNamesStats(t *testing.T) {
 				{MetricName: "metric_name_1", QueryRequestsCount: 3},
 			},
 		}
-		gotStats = vmselect.MetricNamesStats(t, "", "", "", apptest.QueryOpts{Tenant: tenantID})
+		gotStats = vmselect.MetricNamesStats(t, "", "", "", nil, apptest.QueryOpts{Tenant: tenantID})
+		if diff := cmp.Diff(expected, gotStats); diff != "" {
+			t.Errorf("unexpected response tenant: %s (-want, +got):\n%s", tenantID, diff)
+		}
+		expected = apptest.MetricNamesStatsResponse{
+			Records: []at.MetricNamesStatsRecord{
+				{MetricName: "metric_name_1", QueryRequestsCount: 3},
+			},
+		}
+		matchNames := []string{"metric_name_1"}
+		gotStats = vmselect.MetricNamesStats(t, "", "", "", matchNames, apptest.QueryOpts{Tenant: tenantID})
 		if diff := cmp.Diff(expected, gotStats); diff != "" {
 			t.Errorf("unexpected response tenant: %s (-want, +got):\n%s", tenantID, diff)
 		}
@@ -186,14 +196,27 @@ func TestClusterMetricNamesStats(t *testing.T) {
 			{MetricName: "metric_name_1", QueryRequestsCount: 9},
 		},
 	}
-	gotStats := vmselect.MetricNamesStats(t, "", "", "", apptest.QueryOpts{Tenant: "multitenant"})
+	gotStats := vmselect.MetricNamesStats(t, "", "", "", nil, apptest.QueryOpts{Tenant: "multitenant"})
+	if diff := cmp.Diff(expected, gotStats); diff != "" {
+		t.Errorf("unexpected response (-want, +got):\n%s", diff)
+	}
+
+	// verify multitenant stats
+	expected = apptest.MetricNamesStatsResponse{
+		Records: []at.MetricNamesStatsRecord{
+			{MetricName: "metric_name_2", QueryRequestsCount: 3},
+			{MetricName: "metric_name_1", QueryRequestsCount: 9},
+		},
+	}
+	matchNames := []string{"metric_name_2", "metric_name_1"}
+	gotStats = vmselect.MetricNamesStats(t, "", "", "", matchNames, apptest.QueryOpts{Tenant: "multitenant"})
 	if diff := cmp.Diff(expected, gotStats); diff != "" {
 		t.Errorf("unexpected response (-want, +got):\n%s", diff)
 	}
 
 	// reset cache and check empty state
 	vmselect.MetricNamesStatsReset(t, at.QueryOpts{})
-	resp = vmselect.MetricNamesStats(t, "", "", "", apptest.QueryOpts{Tenant: "multitenant"})
+	resp = vmselect.MetricNamesStats(t, "", "", "", nil, apptest.QueryOpts{Tenant: "multitenant"})
 	if len(resp.Records) != 0 {
 		t.Fatalf("want 0 records, got: %d", len(resp.Records))
 	}

apptest/vmselect.go

@@ -139,13 +139,16 @@ func (app *Vmselect) DeleteSeries(t *testing.T, matchQuery string, opts QueryOpt
 // and returns the statistics response for given params.
 //
 // See https://docs.victoriametrics.com/#Trackingestedmetricsusage
-func (app *Vmselect) MetricNamesStats(t *testing.T, limit, le, matchPattern string, opts QueryOpts) MetricNamesStatsResponse {
+func (app *Vmselect) MetricNamesStats(t *testing.T, limit, le, matchPattern string, matchNames []string, opts QueryOpts) MetricNamesStatsResponse {
 	t.Helper()
 
 	values := opts.asURLValues()
 	values.Add("limit", limit)
 	values.Add("le", le)
 	values.Add("match_pattern", matchPattern)
+	for _, mn := range matchNames {
+		values.Add("match_names", mn)
+	}
 	queryURL := fmt.Sprintf("http://%s/select/%s/prometheus/api/v1/status/metric_names_stats", app.httpListenAddr, opts.getTenant())
 
 	res, statusCode := app.cli.PostForm(t, queryURL, values)

docs/victoriametrics/README.md

@@ -483,6 +483,7 @@ To get metric names usage statistics, use the `/prometheus/api/v1/status/metric_
 * `limit` - integer value to limit the number of metric names in response. By default, API returns 1000 records.
 * `le` -  `less than or equal`, is an integer threshold for filtering metric names by their usage count in queries. For example, with `?le=1` API returns metric names that were queried <=1 times.
 * `match_pattern` - a substring pattern to match metric names. For example, `?match_pattern=vm_` will match any metric names with `vm_` pattern, like `vm_http_requests`, `max_vm_memory_available`. It doesn't support regex syntax.
+* `match_names` - a list of metric names to query. If this param is defined, `le` and `match_pattern` options will be ignored.
 
  The API endpoint returns the following `JSON` response:
 

docs/victoriametrics/changelog/CHANGELOG.md

@@ -18,9 +18,12 @@ See also [LTS releases](https://docs.victoriametrics.com/lts-releases/).
 
 ## tip
 
+** update note 1: change vmselect to vmstorage cluster RPC method from `metricNamesUsageStats_v1` to `metricNamesUsageStats_v2`
+
 * FEATURE: all the VictoriaMetrics components: mask `authKey` value from log messages. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5973) for details.
 * FEATURE: [vmsingle](https://docs.victoriametrics.com/single-server-victoriametrics/), [vmagent](https://docs.victoriametrics.com/vmagent/): add helpful hints to the unexpected EOF error message in the write concurrency limiter. See [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/8704) for details.
 * FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent/): use [VM remote write protocol](https://docs.victoriametrics.com/vmagent/#victoriametrics-remote-write-protocol) by default with automatic downgrade in runtime to Prometheus protocol when needed. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/8462) for details.
+* FEATURE: [vmsingle](https://docs.victoriametrics.com/single-server-victoriametrics/) and `vmstorage` in [VictoriaMetrics cluster](https://docs.victoriametrics.com/cluster-victoriametrics/): enhance  - `/api/v1/status/metric_names_stats` [API](https://docs.victoriametrics.com/keyconcepts/#structure-of-a-metric) with `match_names` query param. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6145) for details and related [docs](https://docs.victoriametrics.com/#track-ingested-metrics-usage)
 
 * BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent/): properly init [enterprise](https://docs.victoriametrics.com/enterprise/) version for `linux/arm` and non-CGO buids. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6019) for details.
 * BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent/): remote write client sets correct content encoding header based on actual body content, rather than relying on configuration. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/8650).

lib/storage/metricnamestats/tracker.go

@@ -391,6 +391,71 @@ func (mt *Tracker) GetStatsForTenant(accountID, projectID uint32, limit, le int,
 	return result
 }
 
+// GetStatsForNamesMultitenant returns stats for metric names
+// ignores accountID and projectID
+//
+// SingleNode version must use GetStatsForNamesTenant with 0 account and project IDs
+func (mt *Tracker) GetStatsForNamesMultitenant(names []string) StatsResult {
+	var result StatsResult
+
+	result.CollectedSinceTs = mt.creationTs.Load()
+	result.TotalRecords = mt.currentItemsCount.Load()
+	result.MaxSizeBytes = mt.maxSizeBytes
+	result.CurrentSizeBytes = mt.currentSizeBytes.Load()
+
+	mt.mu.RLock()
+	for sk, si := range mt.store {
+		for _, mn := range names {
+			if mn == sk.metricName {
+				result.Records = append(result.Records, StatRecord{
+					MetricName:    sk.metricName,
+					RequestsCount: si.requestsCount.Load(),
+					LastRequestTs: si.lastRequestTs.Load(),
+				})
+				break
+			}
+		}
+	}
+	mt.mu.RUnlock()
+
+	result.sort()
+	result.DeduplicateMergeRecords()
+	return result
+}
+
+// GetStatsForNamesTenant returns stats for given accountID and projectID
+func (mt *Tracker) GetStatsForNamesTenant(accountID, projectID uint32, names []string) StatsResult {
+	var result StatsResult
+
+	result.CollectedSinceTs = mt.creationTs.Load()
+	result.TotalRecords = mt.currentItemsCount.Load()
+	result.MaxSizeBytes = mt.maxSizeBytes
+	result.CurrentSizeBytes = mt.currentSizeBytes.Load()
+
+	mt.mu.RLock()
+	for _, mn := range names {
+		sk := statKey{
+			accountID:  accountID,
+			projectID:  projectID,
+			metricName: mn,
+		}
+		si, ok := mt.store[sk]
+		if !ok {
+			continue
+		}
+		result.Records = append(result.Records, StatRecord{
+			MetricName:    sk.metricName,
+			RequestsCount: si.requestsCount.Load(),
+			LastRequestTs: si.lastRequestTs.Load(),
+		})
+	}
+
+	mt.mu.RUnlock()
+
+	result.sort()
+	return result
+}
+
 // GetStats returns stats response for the tracked metrics
 //
 // DeduplicateMergeRecords must be called at cluster version on returned result.

lib/storage/metricnamestats/tracker_test.go

@@ -562,3 +562,60 @@ func TestStatsResultMerge(t *testing.T) {
 	f(dst, src, expected)
 
 }
+
+func TestStatsForMetricNames(t *testing.T) {
+	type testOp struct {
+		o  byte
+		mg string
+	}
+
+	umt, err := loadFrom(t.TempDir()+t.Name(), storeOverhead+10*2)
+	if err != nil {
+		t.Fatalf("cannot load tracker: %s", err)
+	}
+	umt.getCurrentTs = func() uint64 { return 1 }
+	ops := []testOp{
+		{'i', "metric_1"},
+		{'r', "metric_2"},
+		{'r', "metric_1"},
+		{'i', "metric_2"},
+		{'i', "metric_3"},
+		{'i', "metric_4"},
+		{'r', "metric_1"},
+		{'r', "metric_2"},
+		{'r', "metric_2"},
+		{'r', "metric_2"},
+	}
+	for _, op := range ops {
+		switch op.o {
+		case 'i':
+			umt.RegisterIngestRequest(0, 0, []byte(op.mg))
+		case 'r':
+			umt.RegisterQueryRequest(0, 0, []byte(op.mg))
+		}
+	}
+
+	f := func(names []string, expected StatsResult) {
+		t.Helper()
+		got := umt.GetStatsForNamesTenant(0, 0, names)
+		if d := cmp.Diff(expected, got, statsResultCmpOpts); len(d) > 0 {
+			t.Fatalf("unexpected deduplicate result: %s", d)
+		}
+	}
+	want := StatsResult{
+		TotalRecords: 2,
+		Records: []StatRecord{
+			{MetricName: "metric_1", RequestsCount: 2, LastRequestTs: 1},
+		},
+	}
+	f([]string{"metric_1", "metric"}, want)
+	want = StatsResult{
+		TotalRecords: 2,
+		Records: []StatRecord{
+			{MetricName: "metric_1", RequestsCount: 2, LastRequestTs: 1},
+			{MetricName: "metric_2", RequestsCount: 3, LastRequestTs: 1},
+		},
+	}
+	f([]string{"metric_1", "metric_2"}, want)
+
+}

lib/storage/storage.go

@@ -3124,12 +3124,32 @@ type MetricNamesStatsResponse = metricnamestats.StatsResult
 // MetricNamesStatsRecord represents record at MetricNamesStatsResponse
 type MetricNamesStatsRecord = metricnamestats.StatRecord
 
-// GetMetricNamesStats returns metric names usage stats with give limit and lte predicate
-func (s *Storage) GetMetricNamesStats(_ *querytracer.Tracer, tt *TenantToken, limit, le int, matchPattern string) MetricNamesStatsResponse {
-	if tt != nil {
-		return s.metricsTracker.GetStatsForTenant(tt.AccountID, tt.ProjectID, limit, le, matchPattern)
+// MetricNamesStatsQuery represents query params for Stats requests
+type MetricNamesStatsQuery struct {
+	TenantToken  *TenantToken
+	Limit        int
+	Le           int
+	MatchPattern string
+	MatchNames   []string
+}
+
+// GetMetricNamesStats returns metric names usage stats for given Query params
+func (s *Storage) GetMetricNamesStats(_ *querytracer.Tracer, statsQuery MetricNamesStatsQuery) MetricNamesStatsResponse {
+
+	if statsQuery.TenantToken != nil {
+		tt := statsQuery.TenantToken
+		if len(statsQuery.MatchNames) > 0 {
+			return s.metricsTracker.GetStatsForNamesTenant(tt.AccountID, tt.ProjectID, statsQuery.MatchNames)
+		}
+
+		return s.metricsTracker.GetStatsForTenant(tt.AccountID, tt.ProjectID, statsQuery.Limit, statsQuery.Le, statsQuery.MatchPattern)
 	}
-	res := s.metricsTracker.GetStats(limit, le, matchPattern)
+
+	var res MetricNamesStatsResponse
+	if len(statsQuery.MatchNames) > 0 {
+		return s.metricsTracker.GetStatsForNamesMultitenant(statsQuery.MatchNames)
+	}
+	res = s.metricsTracker.GetStats(statsQuery.Limit, statsQuery.Le, statsQuery.MatchPattern)
 	res.DeduplicateMergeRecords()
 	return res
 }

lib/storage/storage_test.go

@@ -3471,7 +3471,10 @@ func TestStorageMetricTracker(t *testing.T) {
 
 	var sr Search
 	// check stats for metrics with 0 requests count
-	mus := s.GetMetricNamesStats(nil, nil, 10_000, 0, "")
+	statsQuery := MetricNamesStatsQuery{
+		Limit: 10_000,
+	}
+	mus := s.GetMetricNamesStats(nil, statsQuery)
 	if len(mus.Records) != int(numRows) {
 		t.Fatalf("unexpected Stats records count=%d, want %d records", len(mus.Records), numRows)
 	}
@@ -3487,11 +3490,12 @@ func TestStorageMetricTracker(t *testing.T) {
 	}
 	sr.MustClose()
 
-	mus = s.GetMetricNamesStats(nil, nil, 10_000, 0, "")
+	mus = s.GetMetricNamesStats(nil, statsQuery)
 	if len(mus.Records) != 0 {
 		t.Fatalf("unexpected Stats records count=%d; want 0 records", len(mus.Records))
 	}
-	mus = s.GetMetricNamesStats(nil, nil, 10_000, 1, "")
+	statsQuery.Le = 1
+	mus = s.GetMetricNamesStats(nil, statsQuery)
 	if len(mus.Records) != int(numRows) {
 		t.Fatalf("unexpected Stats records count=%d, want %d records", len(mus.Records), numRows)
 	}

lib/vmselectapi/api.go

@@ -40,7 +40,7 @@ type API interface {
 	Tenants(qt *querytracer.Tracer, tr storage.TimeRange, deadline uint64) ([]string, error)
 
 	// GetMetricNamesUsageStats returns statistics for metric names
-	GetMetricNamesUsageStats(qt *querytracer.Tracer, tt *storage.TenantToken, limit, le int, matchPattern string, deadline uint64) (storage.MetricNamesStatsResponse, error)
+	GetMetricNamesUsageStats(qt *querytracer.Tracer, sq storage.MetricNamesStatsQuery, deadline uint64) (storage.MetricNamesStatsResponse, error)
 
 	// ResetMetricNamesUsageStats resets internal state of metric names tracker
 	ResetMetricNamesUsageStats(qt *querytracer.Tracer, deadline uint64) error

lib/vmselectapi/server.go

@@ -1,6 +1,7 @@
 package vmselectapi
 
 import (
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -348,18 +349,6 @@ func (ctx *vmselectRequestCtx) readUint64() (uint64, error) {
 	return n, nil
 }
 
-func (ctx *vmselectRequestCtx) readInt64() (int64, error) {
-	ctx.sizeBuf = bytesutil.ResizeNoCopyMayOverallocate(ctx.sizeBuf, 8)
-	if _, err := io.ReadFull(ctx.bc, ctx.sizeBuf); err != nil {
-		if err == io.EOF {
-			return 0, err
-		}
-		return 0, fmt.Errorf("cannot read int64: %w", err)
-	}
-	n := encoding.UnmarshalInt64(ctx.sizeBuf)
-	return n, nil
-}
-
 func (ctx *vmselectRequestCtx) readAccountIDProjectID() (uint32, uint32, error) {
 	accountID, err := ctx.readUint32()
 	if err != nil {
@@ -586,7 +575,7 @@ func (s *Server) processRPC(ctx *vmselectRequestCtx, rpcName string) error {
 		return s.processRegisterMetricNames(ctx)
 	case "tenants_v1":
 		return s.processTenants(ctx)
-	case "metricNamesUsageStats_v1":
+	case "metricNamesUsageStats_v2":
 		return s.processMetricNamesUsageStats(ctx)
 	case "resetMetricNamesStats_v1":
 		return s.processResetMetricUsageStats(ctx)
@@ -1076,46 +1065,24 @@ func (s *Server) processSearch(ctx *vmselectRequestCtx) error {
 	return nil
 }
 
+const maxMetricNamesStatsQueryJSONSize = 1024 * 1024
+
 func (s *Server) processMetricNamesUsageStats(ctx *vmselectRequestCtx) error {
 	// Read request.
-	hasTenant, err := ctx.readBool()
-	if err != nil {
-		return fmt.Errorf("cannot read hasTenant: %w", err)
-	}
-	var at *storage.TenantToken
-	if hasTenant {
-		accountID, err := ctx.readUint32()
-		if err != nil {
-			return fmt.Errorf("cannot read accountID: %w", err)
-		}
-		projectID, err := ctx.readUint32()
-		if err != nil {
-			return fmt.Errorf("cannot read projectID: %w", err)
-		}
-		at = &storage.TenantToken{
-			AccountID: accountID,
-			ProjectID: projectID,
-		}
-	}
-	limit, err := ctx.readLimit()
-	if err != nil {
-		return fmt.Errorf("cannot read limit: %w", err)
-	}
-	le, err := ctx.readInt64()
-	if err != nil {
-		return fmt.Errorf("cannot read le: %w", err)
-	}
-	if err := ctx.readDataBufBytes(256); err != nil {
+	if err := ctx.readDataBufBytes(maxMetricNamesStatsQueryJSONSize); err != nil {
 		return fmt.Errorf("cannot read matchPattern: %w", err)
 	}
-	matchPattern := string(ctx.dataBuf)
+	var statsQuery storage.MetricNamesStatsQuery
+	if err := json.Unmarshal(ctx.dataBuf, &statsQuery); err != nil {
+		return fmt.Errorf("cannot parse MetricNamesStatsQuery: %w", err)
+	}
 
 	if err := s.beginConcurrentRequest(ctx); err != nil {
 		return ctx.writeErrorMessage(err)
 	}
 	defer s.endConcurrentRequest()
 
-	result, err := s.api.GetMetricNamesUsageStats(ctx.qt, at, limit, int(le), matchPattern, ctx.deadline)
+	result, err := s.api.GetMetricNamesUsageStats(ctx.qt, statsQuery, ctx.deadline)
 	if err != nil {
 		return ctx.writeErrorMessage(err)
 	}