lib/storage: disable composite index usage when querying old data

app/vmselect/netstorage/netstorage.go

@@ -25,8 +25,6 @@ var (
 	maxTagValuesPerSearch        = flag.Int("search.maxTagValues", 100e3, "The maximum number of tag values returned from /api/v1/label/<label_name>/values")
 	maxTagValueSuffixesPerSearch = flag.Int("search.maxTagValueSuffixesPerSearch", 100e3, "The maximum number of tag value suffixes returned from /metrics/find")
 	maxMetricsPerSearch          = flag.Int("search.maxUniqueTimeseries", 300e3, "The maximum number of unique time series each search can scan")
-	disableCompositeTagFilters   = flag.Bool("search.disableCompositeTagFilters", false, "Whether to disable composite tag filters. This option is useful "+
-		"for querying old data, which is created before v1.54.0 release. Note that disabled composite tag filters may reduce query performance")
 )
 
 // Result is a single timeseries result.
@@ -931,9 +929,6 @@ type blockRef struct {
 func setupTfss(tr storage.TimeRange, tagFilterss [][]storage.TagFilter, deadline searchutils.Deadline) ([]*storage.TagFilters, error) {
 	tfss := make([]*storage.TagFilters, 0, len(tagFilterss))
 	for _, tagFilters := range tagFilterss {
-		if !*disableCompositeTagFilters {
-			tagFilters = storage.ConvertToCompositeTagFilters(tagFilters)
-		}
 		tfs := storage.NewTagFilters()
 		for i := range tagFilters {
 			tf := &tagFilters[i]

docs/CHANGELOG.md

@@ -2,7 +2,7 @@
 
 # tip
 
-* FEATURE: optimize searching for time series by label filters where individual filters match big number of time series (more than a million). For example, the query `up{job="foobar"}` should work faster if `{job="foobar"}` matches a million of time series, while `up{job="foobar"}` matches much lower number of time series. The optimization can be disabled by passing `-search.disableCompositeTagFilters` command-line flag to VictoriaMetrics.
+* FEATURE: optimize searching for time series by label filters where individual filters match big number of time series (more than a million). For example, the query `up{job="foobar"}` should work faster if `{job="foobar"}` matches a million of time series, while `up{job="foobar"}` matches much lower number of time series.
 * FEATURE: single-node VictoriaMetrics now accepts requests to handlers with `/prometheus` and `/graphite` prefixes such as `/prometheus/api/v1/query`. This improves compatibility with [handlers from VictoriaMetrics cluster](https://victoriametrics.github.io/Cluster-VictoriaMetrics.html#url-format).
 * FEATURE: expose `process_open_fds` and `process_max_fds` metrics. These metrics can be used for alerting when `process_open_fds` reaches `process_max_fds`. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/402 and https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1037
 * FEATURE: vmalert: add `-datasource.appendTypePrefix` command-line option for querying both Prometheus and Graphite datasource in cluster version of VictoriaMetrics. See [these docs](https://victoriametrics.github.io/vmalert.html#graphite) for details.

lib/fs/fs.go

@@ -3,6 +3,7 @@ package fs
 import (
 	"fmt"
 	"io"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -257,6 +258,48 @@ func SymlinkRelative(srcPath, dstPath string) error {
 	return os.Symlink(srcPathRel, dstPath)
 }
 
+// CopyDirectory copies all the files in srcPath to dstPath.
+func CopyDirectory(srcPath, dstPath string) error {
+	fis, err := ioutil.ReadDir(srcPath)
+	if err != nil {
+		return err
+	}
+	if err := MkdirAllIfNotExist(dstPath); err != nil {
+		return err
+	}
+	for _, fi := range fis {
+		if !fi.Mode().IsRegular() {
+			// Skip non-files
+			continue
+		}
+		src := filepath.Join(srcPath, fi.Name())
+		dst := filepath.Join(dstPath, fi.Name())
+		if err := copyFile(src, dst); err != nil {
+			return err
+		}
+	}
+	MustSyncPath(dstPath)
+	return nil
+}
+
+func copyFile(srcPath, dstPath string) error {
+	src, err := os.Open(srcPath)
+	if err != nil {
+		return err
+	}
+	defer MustClose(src)
+	dst, err := os.Create(dstPath)
+	if err != nil {
+		return err
+	}
+	defer MustClose(dst)
+	if _, err := io.Copy(dst, src); err != nil {
+		return err
+	}
+	MustSyncPath(dstPath)
+	return nil
+}
+
 // ReadFullData reads len(data) bytes from r.
 func ReadFullData(r io.Reader, data []byte) error {
 	n, err := io.ReadFull(r, data)

lib/storage/index_db.go

@@ -117,10 +117,13 @@ type indexDB struct {
 	// metricIDs, since it usually requires 1 bit per deleted metricID.
 	deletedMetricIDs           atomic.Value
 	deletedMetricIDsUpdateLock sync.Mutex
+
+	// The minimum timestamp when queries with composite index can be used.
+	minTimestampForCompositeIndex int64
 }
 
 // openIndexDB opens index db from the given path with the given caches.
-func openIndexDB(path string, metricIDCache, metricNameCache, tsidCache *workingsetcache.Cache) (*indexDB, error) {
+func openIndexDB(path string, metricIDCache, metricNameCache, tsidCache *workingsetcache.Cache, minTimestampForCompositeIndex int64) (*indexDB, error) {
 	if metricIDCache == nil {
 		logger.Panicf("BUG: metricIDCache must be non-nil")
 	}
@@ -152,6 +155,8 @@ func openIndexDB(path string, metricIDCache, metricNameCache, tsidCache *working
 		tsidCache:                      tsidCache,
 		uselessTagFiltersCache:         workingsetcache.New(mem/128, time.Hour),
 		metricIDsPerDateTagFilterCache: workingsetcache.New(mem/128, time.Hour),
+
+		minTimestampForCompositeIndex: minTimestampForCompositeIndex,
 	}
 
 	is := db.getIndexSearch(noDeadline)
@@ -1628,6 +1633,9 @@ func (db *indexDB) searchTSIDs(tfss []*TagFilters, tr TimeRange, maxMetrics int,
 	if len(tfss) == 0 {
 		return nil, nil
 	}
+	if tr.MinTimestamp >= db.minTimestampForCompositeIndex {
+		tfss = convertToCompositeTagFilterss(tfss)
+	}
 
 	tfKeyBuf := tagFiltersKeyBufPool.Get()
 	defer tagFiltersKeyBufPool.Put(tfKeyBuf)
@@ -1886,8 +1894,8 @@ func (is *indexSearch) updateMetricIDsByMetricNameMatch(metricIDs, srcMetricIDs
 	sortedMetricIDs := srcMetricIDs.AppendTo(nil)
 
 	kb := &is.kb
-	kb.B = marshalCommonPrefix(kb.B[:0], nsPrefixTagToMetricIDs)
+	kb.B = is.marshalCommonPrefix(kb.B[:0], nsPrefixTagToMetricIDs)
-	tfs = fromCompositeTagFilters(tfs, kb.B)
+	tfs = removeCompositeTagFilters(tfs, kb.B)
 
 	metricName := kbPool.Get()
 	defer kbPool.Put(metricName)
@@ -2090,17 +2098,21 @@ func (is *indexSearch) getTagFilterWithMinMetricIDsCount(tfs *TagFilters, maxMet
 	return nil, metricIDs, nil
 }
 
-func fromCompositeTagFilters(tfs []*tagFilter, prefix []byte) []*tagFilter {
+func removeCompositeTagFilters(tfs []*tagFilter, prefix []byte) []*tagFilter {
-	tfsNew := make([]*tagFilter, 0, len(tfs))
+	if !hasCompositeTagFilters(tfs, prefix) {
+		return tfs
+	}
+	var tagKey []byte
+	var name []byte
+	tfsNew := make([]*tagFilter, 0, len(tfs)+1)
 	for _, tf := range tfs {
 		if !bytes.HasPrefix(tf.prefix, prefix) {
 			tfsNew = append(tfsNew, tf)
 			continue
 		}
 		suffix := tf.prefix[len(prefix):]
-		var tagKey, tail []byte
 		var err error
-		tail, tagKey, err = unmarshalTagValue(tagKey[:0], suffix)
+		_, tagKey, err = unmarshalTagValue(tagKey[:0], suffix)
 		if err != nil {
 			logger.Panicf("BUG: cannot unmarshal tag key from suffix=%q: %s", suffix, err)
 		}
@@ -2114,20 +2126,49 @@ func fromCompositeTagFilters(tfs []*tagFilter, prefix []byte) []*tagFilter {
 		if err != nil {
 			logger.Panicf("BUG: cannot unmarshal nameLen from tagKey %q: %s", tagKey, err)
 		}
+		if nameLen == 0 {
+			logger.Panicf("BUG: nameLen must be greater than 0")
+		}
 		if uint64(len(tagKey)) < nameLen {
 			logger.Panicf("BUG: expecting at %d bytes for name in tagKey=%q; got %d bytes", nameLen, tagKey, len(tagKey))
 		}
+		name = append(name[:0], tagKey[:nameLen]...)
 		tagKey = tagKey[nameLen:]
-		tfNew := *tf
+		var tfNew tagFilter
-		tfNew.key = append(tfNew.key[:0], tagKey...)
+		if err := tfNew.Init(prefix, tagKey, tf.value, tf.isNegative, tf.isRegexp); err != nil {
-		tfNew.prefix = append(tfNew.prefix[:0], prefix...)
+			logger.Panicf("BUG: cannot initialize {%s=%q} filter: %s", tagKey, tf.value, err)
-		tfNew.prefix = marshalTagValue(tfNew.prefix, tagKey)
+		}
-		tfNew.prefix = append(tfNew.prefix, tail...)
+		tfsNew = append(tfsNew, &tfNew)
+	}
+	if len(name) > 0 {
+		var tfNew tagFilter
+		if err := tfNew.Init(prefix, nil, name, false, false); err != nil {
+			logger.Panicf("BUG: unexpected error when initializing {__name__=%q} filter: %s", name, err)
+		}
 		tfsNew = append(tfsNew, &tfNew)
 	}
 	return tfsNew
 }
 
+func hasCompositeTagFilters(tfs []*tagFilter, prefix []byte) bool {
+	var tagKey []byte
+	for _, tf := range tfs {
+		if !bytes.HasPrefix(tf.prefix, prefix) {
+			continue
+		}
+		suffix := tf.prefix[len(prefix):]
+		var err error
+		_, tagKey, err = unmarshalTagValue(tagKey[:0], suffix)
+		if err != nil {
+			logger.Panicf("BUG: cannot unmarshal tag key from suffix=%q: %s", suffix, err)
+		}
+		if len(tagKey) > 0 && tagKey[0] == compositeTagKeyPrefix {
+			return true
+		}
+	}
+	return false
+}
+
 func matchTagFilters(mn *MetricName, tfs []*tagFilter, kb *bytesutil.ByteBuffer) (bool, error) {
 	kb.B = marshalCommonPrefix(kb.B[:0], nsPrefixTagToMetricIDs)
 	for i, tf := range tfs {

lib/storage/index_db_test.go

@@ -456,7 +456,7 @@ func TestIndexDBOpenClose(t *testing.T) {
 	defer tsidCache.Stop()
 
 	for i := 0; i < 5; i++ {
-		db, err := openIndexDB("test-index-db", metricIDCache, metricNameCache, tsidCache)
+		db, err := openIndexDB("test-index-db", metricIDCache, metricNameCache, tsidCache, 0)
 		if err != nil {
 			t.Fatalf("cannot open indexDB: %s", err)
 		}
@@ -479,7 +479,7 @@ func TestIndexDB(t *testing.T) {
 		defer tsidCache.Stop()
 
 		dbName := "test-index-db-serial"
-		db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache)
+		db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache, 0)
 		if err != nil {
 			t.Fatalf("cannot open indexDB: %s", err)
 		}
@@ -509,7 +509,7 @@ func TestIndexDB(t *testing.T) {
 
 		// Re-open the db and verify it works as expected.
 		db.MustClose()
-		db, err = openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache)
+		db, err = openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache, 0)
 		if err != nil {
 			t.Fatalf("cannot open indexDB: %s", err)
 		}
@@ -533,7 +533,7 @@ func TestIndexDB(t *testing.T) {
 		defer tsidCache.Stop()
 
 		dbName := "test-index-db-concurrent"
-		db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache)
+		db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache, 0)
 		if err != nil {
 			t.Fatalf("cannot open indexDB: %s", err)
 		}
@@ -1465,7 +1465,7 @@ func TestSearchTSIDWithTimeRange(t *testing.T) {
 	defer tsidCache.Stop()
 
 	dbName := "test-index-db-ts-range"
-	db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache)
+	db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache, 0)
 	if err != nil {
 		t.Fatalf("cannot open indexDB: %s", err)
 	}

lib/storage/index_db_timing_test.go

@@ -50,7 +50,7 @@ func BenchmarkIndexDBAddTSIDs(b *testing.B) {
 	defer tsidCache.Stop()
 
 	const dbName = "bench-index-db-add-tsids"
-	db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache)
+	db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache, 0)
 	if err != nil {
 		b.Fatalf("cannot open indexDB: %s", err)
 	}
@@ -115,7 +115,7 @@ func BenchmarkHeadPostingForMatchers(b *testing.B) {
 	defer tsidCache.Stop()
 
 	const dbName = "bench-head-posting-for-matchers"
-	db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache)
+	db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache, 0)
 	if err != nil {
 		b.Fatalf("cannot open indexDB: %s", err)
 	}
@@ -294,7 +294,7 @@ func BenchmarkIndexDBGetTSIDs(b *testing.B) {
 	defer tsidCache.Stop()
 
 	const dbName = "bench-index-db-get-tsids"
-	db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache)
+	db, err := openIndexDB(dbName, metricIDCache, metricNameCache, tsidCache, 0)
 	if err != nil {
 		b.Fatalf("cannot open indexDB: %s", err)
 	}

lib/storage/storage.go

@@ -108,6 +108,9 @@ type Storage struct {
 	// which may be in the process of flushing to disk by concurrently running
 	// snapshot process.
 	snapshotLock sync.Mutex
+
+	// The minimum timestamp when composite index search can be used.
+	minTimestampForCompositeIndex int64
 }
 
 // OpenStorage opens storage on the given path with the given retentionMsecs.
@@ -126,14 +129,9 @@ func OpenStorage(path string, retentionMsecs int64) (*Storage, error) {
 
 		stop: make(chan struct{}),
 	}
-
 	if err := fs.MkdirAllIfNotExist(path); err != nil {
 		return nil, fmt.Errorf("cannot create a directory for the storage at %q: %w", path, err)
 	}
-	snapshotsPath := path + "/snapshots"
-	if err := fs.MkdirAllIfNotExist(snapshotsPath); err != nil {
-		return nil, fmt.Errorf("cannot create %q: %w", snapshotsPath, err)
-	}
 
 	// Protect from concurrent opens.
 	flockF, err := fs.CreateFlockFile(path)
@@ -142,6 +140,12 @@ func OpenStorage(path string, retentionMsecs int64) (*Storage, error) {
 	}
 	s.flockF = flockF
 
+	// Pre-create snapshots directory if it is missing.
+	snapshotsPath := path + "/snapshots"
+	if err := fs.MkdirAllIfNotExist(snapshotsPath); err != nil {
+		return nil, fmt.Errorf("cannot create %q: %w", snapshotsPath, err)
+	}
+
 	// Load caches.
 	mem := memory.Allowed()
 	s.tsidCache = s.mustLoadCache("MetricName->TSID", "metricName_tsid", mem/3)
@@ -166,10 +170,11 @@ func OpenStorage(path string, retentionMsecs int64) (*Storage, error) {
 	// Load indexdb
 	idbPath := path + "/indexdb"
 	idbSnapshotsPath := idbPath + "/snapshots"
+	isEmptyDB := !fs.IsPathExist(idbPath)
 	if err := fs.MkdirAllIfNotExist(idbSnapshotsPath); err != nil {
 		return nil, fmt.Errorf("cannot create %q: %w", idbSnapshotsPath, err)
 	}
-	idbCurr, idbPrev, err := openIndexDBTables(idbPath, s.metricIDCache, s.metricNameCache, s.tsidCache)
+	idbCurr, idbPrev, err := openIndexDBTables(idbPath, s.metricIDCache, s.metricNameCache, s.tsidCache, s.minTimestampForCompositeIndex)
 	if err != nil {
 		return nil, fmt.Errorf("cannot open indexdb tables at %q: %w", idbPath, err)
 	}
@@ -185,6 +190,13 @@ func OpenStorage(path string, retentionMsecs int64) (*Storage, error) {
 	}
 	s.tb = tb
 
+	// Load metadata
+	metadataDir := path + "/metadata"
+	if err := fs.MkdirAllIfNotExist(metadataDir); err != nil {
+		return nil, fmt.Errorf("cannot create %q: %w", metadataDir, err)
+	}
+	s.minTimestampForCompositeIndex = mustGetMinTimestampForCompositeIndex(metadataDir, isEmptyDB)
+
 	s.startCurrHourMetricIDsUpdater()
 	s.startNextDayMetricIDsUpdater()
 	s.startRetentionWatcher()
@@ -235,7 +247,7 @@ func (s *Storage) CreateSnapshot() (string, error) {
 	}
 	fs.MustSyncPath(dstDataDir)
 
-	idbSnapshot := fmt.Sprintf("%s/indexdb/snapshots/%s", s.path, snapshotName)
+	idbSnapshot := fmt.Sprintf("%s/indexdb/snapshots/%s", srcDir, snapshotName)
 	idb := s.idb()
 	currSnapshot := idbSnapshot + "/" + idb.name
 	if err := idb.tb.CreateSnapshotAt(currSnapshot); err != nil {
@@ -253,8 +265,13 @@ func (s *Storage) CreateSnapshot() (string, error) {
 		return "", fmt.Errorf("cannot create symlink from %q to %q: %w", idbSnapshot, dstIdbDir, err)
 	}
 
+	srcMetadataDir := srcDir + "/metadata"
+	dstMetadataDir := dstDir + "/metadata"
+	if err := fs.CopyDirectory(srcMetadataDir, dstMetadataDir); err != nil {
+		return "", fmt.Errorf("cannot copy metadata: %s", err)
+	}
+
 	fs.MustSyncPath(dstDir)
-	fs.MustSyncPath(srcDir + "/snapshots")
 
 	logger.Infof("created Storage snapshot for %q at %q in %.3f seconds", srcDir, dstDir, time.Since(startTime).Seconds())
 	return snapshotName, nil
@@ -537,7 +554,7 @@ func (s *Storage) mustRotateIndexDB() {
 	// Create new indexdb table.
 	newTableName := nextIndexDBTableName()
 	idbNewPath := s.path + "/indexdb/" + newTableName
-	idbNew, err := openIndexDB(idbNewPath, s.metricIDCache, s.metricNameCache, s.tsidCache)
+	idbNew, err := openIndexDB(idbNewPath, s.metricIDCache, s.metricNameCache, s.tsidCache, s.minTimestampForCompositeIndex)
 	if err != nil {
 		logger.Panicf("FATAL: cannot create new indexDB at %q: %s", idbNewPath, err)
 	}
@@ -758,6 +775,43 @@ func marshalUint64Set(dst []byte, m *uint64set.Set) []byte {
 	return dst
 }
 
+func mustGetMinTimestampForCompositeIndex(metadataDir string, isEmptyDB bool) int64 {
+	path := metadataDir + "/minTimestampForCompositeIndex"
+	minTimestamp, err := loadMinTimestampForCompositeIndex(path)
+	if err == nil {
+		return minTimestamp
+	}
+	logger.Errorf("cannot read minTimestampForCompositeIndex, so trying to re-create it; error: %s", err)
+	date := time.Now().UnixNano() / 1e6 / msecPerDay
+	if !isEmptyDB {
+		// The current and the next day can already contain non-composite indexes,
+		// so they cannot be queried with composite indexes.
+		date += 2
+	} else {
+		date = 0
+	}
+	minTimestamp = date * msecPerDay
+	dateBuf := encoding.MarshalInt64(nil, minTimestamp)
+	if err := os.RemoveAll(path); err != nil {
+		logger.Fatalf("cannot remove a file with minTimestampForCompositeIndex: %s", err)
+	}
+	if err := fs.WriteFileAtomically(path, dateBuf); err != nil {
+		logger.Fatalf("cannot store minTimestampForCompositeIndex: %s", err)
+	}
+	return minTimestamp
+}
+
+func loadMinTimestampForCompositeIndex(path string) (int64, error) {
+	data, err := ioutil.ReadFile(path)
+	if err != nil {
+		return 0, err
+	}
+	if len(data) != 8 {
+		return 0, fmt.Errorf("unexpected length of %q; got %d bytes; want 8 bytes", path, len(data))
+	}
+	return encoding.UnmarshalInt64(data), nil
+}
+
 func (s *Storage) mustLoadCache(info, name string, sizeBytes int) *workingsetcache.Cache {
 	path := s.cachePath + "/" + name
 	logger.Infof("loading %s cache from %q...", info, path)
@@ -1948,7 +2002,7 @@ func (s *Storage) putTSIDToCache(tsid *TSID, metricName []byte) {
 	s.tsidCache.Set(metricName, buf)
 }
 
-func openIndexDBTables(path string, metricIDCache, metricNameCache, tsidCache *workingsetcache.Cache) (curr, prev *indexDB, err error) {
+func openIndexDBTables(path string, metricIDCache, metricNameCache, tsidCache *workingsetcache.Cache, minTimestampForCompositeIndex int64) (curr, prev *indexDB, err error) {
 	if err := fs.MkdirAllIfNotExist(path); err != nil {
 		return nil, nil, fmt.Errorf("cannot create directory %q: %w", path, err)
 	}
@@ -2007,12 +2061,12 @@ func openIndexDBTables(path string, metricIDCache, metricNameCache, tsidCache *w
 	// Open the last two tables.
 	currPath := path + "/" + tableNames[len(tableNames)-1]
 
-	curr, err = openIndexDB(currPath, metricIDCache, metricNameCache, tsidCache)
+	curr, err = openIndexDB(currPath, metricIDCache, metricNameCache, tsidCache, minTimestampForCompositeIndex)
 	if err != nil {
 		return nil, nil, fmt.Errorf("cannot open curr indexdb table at %q: %w", currPath, err)
 	}
 	prevPath := path + "/" + tableNames[len(tableNames)-2]
-	prev, err = openIndexDB(prevPath, metricIDCache, metricNameCache, tsidCache)
+	prev, err = openIndexDB(prevPath, metricIDCache, metricNameCache, tsidCache, minTimestampForCompositeIndex)
 	if err != nil {
 		curr.MustClose()
 		return nil, nil, fmt.Errorf("cannot open prev indexdb table at %q: %w", prevPath, err)

lib/storage/tag_filters.go

@@ -14,15 +14,23 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/memory"
 )
 
-// ConvertToCompositeTagFilters converts tfs to composite filters.
+// convertToCompositeTagFilterss converts tfss to composite filters.
 //
 // This converts `foo{bar="baz",x=~"a.+"}` to `{foo=bar="baz",foo=x=~"a.+"} filter.
-func ConvertToCompositeTagFilters(tfs []TagFilter) []TagFilter {
+func convertToCompositeTagFilterss(tfss []*TagFilters) []*TagFilters {
+	tfssNew := make([]*TagFilters, len(tfss))
+	for i, tfs := range tfss {
+		tfssNew[i] = convertToCompositeTagFilters(tfs)
+	}
+	return tfssNew
+}
+
+func convertToCompositeTagFilters(tfs *TagFilters) *TagFilters {
 	// Search for metric name filter, which must be used for creating composite filters.
 	var name []byte
-	for _, tf := range tfs {
+	for _, tf := range tfs.tfs {
-		if len(tf.Key) == 0 && !tf.IsNegative && !tf.IsRegexp {
+		if len(tf.key) == 0 && !tf.isNegative && !tf.isRegexp {
-			name = tf.Value
+			name = tf.value
 			break
 		}
 	}
@@ -30,33 +38,34 @@ func ConvertToCompositeTagFilters(tfs []TagFilter) []TagFilter {
 		// There is no metric name filter, so composite filters cannot be created.
 		return tfs
 	}
-	tfsNew := make([]TagFilter, 0, len(tfs))
+	tfsNew := make([]tagFilter, 0, len(tfs.tfs))
 	var compositeKey []byte
 	compositeFilters := 0
-	for _, tf := range tfs {
+	for _, tf := range tfs.tfs {
-		if len(tf.Key) == 0 {
+		if len(tf.key) == 0 {
-			if tf.IsNegative || tf.IsRegexp || string(tf.Value) != string(name) {
+			if tf.isNegative || tf.isRegexp || string(tf.value) != string(name) {
 				tfsNew = append(tfsNew, tf)
 			}
 			continue
 		}
-		if string(tf.Key) == "__graphite__" {
+		if string(tf.key) == "__graphite__" {
 			tfsNew = append(tfsNew, tf)
 			continue
 		}
-		compositeKey = marshalCompositeTagKey(compositeKey[:0], name, tf.Key)
+		compositeKey = marshalCompositeTagKey(compositeKey[:0], name, tf.key)
-		tfsNew = append(tfsNew, TagFilter{
+		var tfNew tagFilter
-			Key:        append([]byte{}, compositeKey...),
+		if err := tfNew.Init(tfs.commonPrefix, compositeKey, tf.value, tf.isNegative, tf.isRegexp); err != nil {
-			Value:      append([]byte{}, tf.Value...),
+			logger.Panicf("BUG: unexpected error when creating composite tag filter for name=%q and key=%q: %s", name, tf.key, err)
-			IsNegative: tf.IsNegative,
+		}
-			IsRegexp:   tf.IsRegexp,
+		tfsNew = append(tfsNew, tfNew)
-		})
 		compositeFilters++
 	}
 	if compositeFilters == 0 {
 		return tfs
 	}
-	return tfsNew
+	tfsCompiled := NewTagFilters()
+	tfsCompiled.tfs = tfsNew
+	return tfsCompiled
 }
 
 // TagFilters represents filters used for filtering tags.

lib/storage/tag_filters_test.go

@@ -9,13 +9,29 @@ import (
 func TestConvertToCompositeTagFilters(t *testing.T) {
 	f := func(tfs, resultExpected []TagFilter) {
 		t.Helper()
-		result := ConvertToCompositeTagFilters(tfs)
+		tfsCompiled := NewTagFilters()
+		for _, tf := range tfs {
+			if err := tfsCompiled.Add(tf.Key, tf.Value, tf.IsNegative, tf.IsRegexp); err != nil {
+				t.Fatalf("cannot add tf=%s: %s", tf.String(), err)
+			}
+		}
+		resultCompiled := convertToCompositeTagFilters(tfsCompiled)
+		result := make([]TagFilter, len(resultCompiled.tfs))
+		for i, tf := range resultCompiled.tfs {
+			result[i] = TagFilter{
+				Key:        tf.key,
+				Value:      tf.value,
+				IsNegative: tf.isNegative,
+				IsRegexp:   tf.isRegexp,
+			}
+		}
 		if !reflect.DeepEqual(result, resultExpected) {
 			t.Fatalf("unexpected result;\ngot\n%+v\nwant\n%+v", result, resultExpected)
 		}
 	}
+
 	// Empty filters
-	f(nil, nil)
+	f(nil, []TagFilter{})
 
 	// A single non-name filter
 	f([]TagFilter{
@@ -167,7 +183,7 @@ func TestConvertToCompositeTagFilters(t *testing.T) {
 		},
 	})
 
-	// A name filter with negative regexp non-name filter.
+	// A name filter with negative regexp non-name filter, which can be converted to non-regexp.
 	f([]TagFilter{
 		{
 			Key:        nil,
@@ -186,6 +202,29 @@ func TestConvertToCompositeTagFilters(t *testing.T) {
 			Key:        []byte("\xfe\x03barfoo"),
 			Value:      []byte("abc"),
 			IsNegative: true,
+			IsRegexp:   false,
+		},
+	})
+
+	// A name filter with negative regexp non-name filter.
+	f([]TagFilter{
+		{
+			Key:        nil,
+			Value:      []byte("bar"),
+			IsNegative: false,
+			IsRegexp:   false,
+		},
+		{
+			Key:        []byte("foo"),
+			Value:      []byte("abc.+"),
+			IsNegative: true,
+			IsRegexp:   true,
+		},
+	}, []TagFilter{
+		{
+			Key:        []byte("\xfe\x03barfoo"),
+			Value:      []byte("abc.+"),
+			IsNegative: true,
 			IsRegexp:   true,
 		},
 	})
@@ -244,7 +283,7 @@ func TestConvertToCompositeTagFilters(t *testing.T) {
 			Key:        []byte("\xfe\x03barfoo"),
 			Value:      []byte("abc"),
 			IsNegative: true,
-			IsRegexp:   true,
+			IsRegexp:   false,
 		},
 		{
 			Key:        []byte("__graphite__"),
@@ -254,7 +293,7 @@ func TestConvertToCompositeTagFilters(t *testing.T) {
 		},
 	})
 
-	// Regexp name filter with non-name filter.
+	// Regexp name filter, which can be converted to non-regexp, with non-name filter.
 	f([]TagFilter{
 		{
 			Key:        nil,
@@ -269,9 +308,19 @@ func TestConvertToCompositeTagFilters(t *testing.T) {
 			IsRegexp:   false,
 		},
 	}, []TagFilter{
+		{
+			Key:        []byte("\xfe\x03barfoo"),
+			Value:      []byte("abc"),
+			IsNegative: true,
+			IsRegexp:   false,
+		},
+	})
+
+	// Regexp name filter with non-name filter.
+	f([]TagFilter{
 		{
 			Key:        nil,
-			Value:      []byte("bar"),
+			Value:      []byte("bar.+"),
 			IsNegative: false,
 			IsRegexp:   true,
 		},
@@ -281,6 +330,42 @@ func TestConvertToCompositeTagFilters(t *testing.T) {
 			IsNegative: true,
 			IsRegexp:   false,
 		},
+	}, []TagFilter{
+		{
+			Key:        nil,
+			Value:      []byte("bar.+"),
+			IsNegative: false,
+			IsRegexp:   true,
+		},
+		{
+			Key:        []byte("foo"),
+			Value:      []byte("abc"),
+			IsNegative: true,
+			IsRegexp:   false,
+		},
+	})
+
+	// Regexp non-name filter, which matches anything.
+	f([]TagFilter{
+		{
+			Key:        nil,
+			Value:      []byte("bar"),
+			IsNegative: false,
+			IsRegexp:   false,
+		},
+		{
+			Key:        []byte("foo"),
+			Value:      []byte(".*"),
+			IsNegative: false,
+			IsRegexp:   true,
+		},
+	}, []TagFilter{
+		{
+			Key:        nil,
+			Value:      []byte("bar"),
+			IsNegative: false,
+			IsRegexp:   false,
+		},
 	})
 }