diff --git a/app/vmselect/netstorage/netstorage.go b/app/vmselect/netstorage/netstorage.go
index 70e585043c..ff0ecc7b5f 100644
--- a/app/vmselect/netstorage/netstorage.go
+++ b/app/vmselect/netstorage/netstorage.go
@@ -115,7 +115,7 @@ func timeseriesWorker(workerID uint) {
 	}
 }
 
-// RunParallel runs in parallel f for all the results from rss.
+// RunParallel runs f in parallel for all the results from rss.
 //
 // f shouldn't hold references to rs after returning.
 // workerID is the id of the worker goroutine that calls f.
diff --git a/lib/storage/index_db.go b/lib/storage/index_db.go
index a480b494fa..bf63561d22 100644
--- a/lib/storage/index_db.go
+++ b/lib/storage/index_db.go
@@ -20,6 +20,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/memory"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/mergeset"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storagepacelimiter"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/uint64set"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/workingsetcache"
 	"github.com/VictoriaMetrics/fastcache"
@@ -783,10 +784,15 @@ func (is *indexSearch) searchTagKeys(accountID, projectID uint32, tks map[string
 	mp := &is.mp
 	mp.Reset()
 	dmis := is.db.getDeletedMetricIDs()
+	loopsPaceLimiter := 0
 	kb.B = marshalCommonPrefix(kb.B[:0], nsPrefixTagToMetricIDs, accountID, projectID)
 	prefix := kb.B
 	ts.Seek(prefix)
 	for len(tks) < maxTagKeys && ts.NextItem() {
+		if loopsPaceLimiter&(1<<16) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		loopsPaceLimiter++
 		item := ts.Item
 		if !bytes.HasPrefix(item, prefix) {
 			break
@@ -855,11 +861,16 @@ func (is *indexSearch) searchTagValues(accountID, projectID uint32, tvs map[stri
 	mp := &is.mp
 	mp.Reset()
 	dmis := is.db.getDeletedMetricIDs()
+	loopsPaceLimiter := 0
 	kb.B = marshalCommonPrefix(kb.B[:0], nsPrefixTagToMetricIDs, accountID, projectID)
 	kb.B = marshalTagValue(kb.B, tagKey)
 	prefix := kb.B
 	ts.Seek(prefix)
 	for len(tvs) < maxTagValues && ts.NextItem() {
+		if loopsPaceLimiter&(1<<16) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		loopsPaceLimiter++
 		item := ts.Item
 		if !bytes.HasPrefix(item, prefix) {
 			break
@@ -923,12 +934,17 @@ func (is *indexSearch) getSeriesCount(accountID, projectID uint32) (uint64, erro
 	ts := &is.ts
 	kb := &is.kb
 	mp := &is.mp
+	loopsPaceLimiter := 0
 	var metricIDsLen uint64
 	// Extract the number of series from ((__name__=value): metricIDs) rows
 	kb.B = marshalCommonPrefix(kb.B[:0], nsPrefixTagToMetricIDs, accountID, projectID)
 	kb.B = marshalTagValue(kb.B, nil)
 	ts.Seek(kb.B)
 	for ts.NextItem() {
+		if loopsPaceLimiter&(1<<16) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		loopsPaceLimiter++
 		item := ts.Item
 		if !bytes.HasPrefix(item, kb.B) {
 			break
@@ -989,11 +1005,16 @@ func (is *indexSearch) getTSDBStatusForDate(accountID, projectID uint32, date ui
 	var labelValueCountByLabelName, seriesCountByLabelValuePair uint64
 	nameEqualBytes := []byte("__name__=")
 
+	loopsPaceLimiter := 0
 	kb.B = marshalCommonPrefix(kb.B[:0], nsPrefixDateTagToMetricIDs, accountID, projectID)
 	kb.B = encoding.MarshalUint64(kb.B, date)
 	prefix := kb.B
 	ts.Seek(prefix)
 	for ts.NextItem() {
+		if loopsPaceLimiter&(1<<16) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		loopsPaceLimiter++
 		item := ts.Item
 		if !bytes.HasPrefix(item, prefix) {
 			break
@@ -1523,7 +1544,10 @@ func (is *indexSearch) searchTSIDs(tfss []*TagFilters, tr TimeRange, maxMetrics
 	// Obtain TSID values for the given metricIDs.
 	tsids := make([]TSID, len(metricIDs))
 	i := 0
-	for _, metricID := range metricIDs {
+	for loopsPaceLimiter, metricID := range metricIDs {
+		if loopsPaceLimiter&(1<<10) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
 		// Try obtaining TSIDs from MetricID->TSID cache. This is much faster
 		// than scanning the mergeset if it contains a lot of metricIDs.
 		tsid := &tsids[i]
@@ -1590,7 +1614,10 @@ func (is *indexSearch) updateMetricIDsByMetricNameMatch(metricIDs, srcMetricIDs
 	defer kbPool.Put(metricName)
 	mn := GetMetricName()
 	defer PutMetricName(mn)
-	for _, metricID := range sortedMetricIDs {
+	for loopsPaceLimiter, metricID := range sortedMetricIDs {
+		if loopsPaceLimiter&(1<<10) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
 		var err error
 		metricName.B, err = is.searchMetricName(metricName.B[:0], metricID, accountID, projectID)
 		if err != nil {
@@ -2063,16 +2090,21 @@ func (is *indexSearch) getMetricIDsForTagFilterSlow(tf *tagFilter, maxLoops int,
 	}
 
 	// Scan all the rows with tf.prefix and call f on every tf match.
-	loops := 0
 	ts := &is.ts
 	kb := &is.kb
 	mp := &is.mp
 	mp.Reset()
 	var prevMatchingSuffix []byte
 	var prevMatch bool
+	loops := 0
+	loopsPaceLimiter := 0
 	prefix := tf.prefix
 	ts.Seek(prefix)
 	for ts.NextItem() {
+		if loopsPaceLimiter&(1<<14) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		loopsPaceLimiter++
 		item := ts.Item
 		if !bytes.HasPrefix(item, prefix) {
 			return nil
@@ -2188,8 +2220,13 @@ func (is *indexSearch) updateMetricIDsForOrSuffixNoFilter(prefix []byte, maxMetr
 	mp.Reset()
 	maxLoops := maxMetrics * maxIndexScanLoopsPerMetric
 	loops := 0
+	loopsPaceLimiter := 0
 	ts.Seek(prefix)
 	for metricIDs.Len() < maxMetrics && ts.NextItem() {
+		if loopsPaceLimiter&(1<<16) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		loopsPaceLimiter++
 		item := ts.Item
 		if !bytes.HasPrefix(item, prefix) {
 			return nil
@@ -2221,10 +2258,15 @@ func (is *indexSearch) updateMetricIDsForOrSuffixWithFilter(prefix []byte, metri
 	mp.Reset()
 	maxLoops := len(sortedFilter) * maxIndexScanLoopsPerMetric
 	loops := 0
+	loopsPaceLimiter := 0
 	ts.Seek(prefix)
 	var sf []uint64
 	var metricID uint64
 	for ts.NextItem() {
+		if loopsPaceLimiter&(1<<12) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		loopsPaceLimiter++
 		item := ts.Item
 		if !bytes.HasPrefix(item, prefix) {
 			return nil
@@ -2768,8 +2810,13 @@ func (is *indexSearch) updateMetricIDsAll(metricIDs *uint64set.Set, accountID, p
 func (is *indexSearch) updateMetricIDsForPrefix(prefix []byte, metricIDs *uint64set.Set, maxMetrics int) error {
 	ts := &is.ts
 	mp := &is.mp
+	loopsPaceLimiter := 0
 	ts.Seek(prefix)
 	for ts.NextItem() {
+		if loopsPaceLimiter&(1<<16) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		loopsPaceLimiter++
 		item := ts.Item
 		if !bytes.HasPrefix(item, prefix) {
 			return nil
diff --git a/lib/storage/search.go b/lib/storage/search.go
index 3a2929c913..082d70f347 100644
--- a/lib/storage/search.go
+++ b/lib/storage/search.go
@@ -7,6 +7,7 @@ import (
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storagepacelimiter"
 )
 
 // BlockRef references a Block.
@@ -131,6 +132,8 @@ type Search struct {
 	err error
 
 	needClosing bool
+
+	loops int
 }
 
 func (s *Search) reset() {
@@ -141,6 +144,7 @@ func (s *Search) reset() {
 	s.ts.reset()
 	s.err = nil
 	s.needClosing = false
+	s.loops = 0
 }
 
 // Init initializes s from the given storage, tfss and tr.
@@ -194,6 +198,10 @@ func (s *Search) NextMetricBlock() bool {
 		return false
 	}
 	for s.ts.NextBlock() {
+		if s.loops&(1<<10) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		s.loops++
 		tsid := &s.ts.BlockRef.bh.TSID
 		var err error
 		s.MetricBlockRef.MetricName, err = s.storage.searchMetricName(s.MetricBlockRef.MetricName[:0], tsid.MetricID, tsid.AccountID, tsid.ProjectID)
diff --git a/lib/storage/storage.go b/lib/storage/storage.go
index 7d1f8fbade..431800d1f7 100644
--- a/lib/storage/storage.go
+++ b/lib/storage/storage.go
@@ -863,11 +863,6 @@ func nextRetentionDuration(retentionMonths int) time.Duration {
 
 // searchTSIDs returns sorted TSIDs for the given tfss and the given tr.
 func (s *Storage) searchTSIDs(tfss []*TagFilters, tr TimeRange, maxMetrics int) ([]TSID, error) {
-	// Make sure that there are enough resources for processing data ingestion before starting the query.
-	// This should prevent from data ingestion starvation when provessing heavy queries.
-	// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/291 .
-	storagepacelimiter.Search.WaitIfNeeded()
-
 	// Do not cache tfss -> tsids here, since the caching is performed
 	// on idb level.
 	tsids, err := s.idb().searchTSIDs(tfss, tr, maxMetrics)
@@ -879,18 +874,27 @@ func (s *Storage) searchTSIDs(tfss []*TagFilters, tr TimeRange, maxMetrics int)
 
 // prefetchMetricNames pre-fetches metric names for the given tsids into metricID->metricName cache.
 //
+// It is expected that all the tsdis have the same (accountID, projectID)
+//
 // This should speed-up further searchMetricName calls for metricIDs from tsids.
 func (s *Storage) prefetchMetricNames(tsids []TSID) error {
+	if len(tsids) == 0 {
+		return nil
+	}
+	accountID := tsids[0].AccountID
+	projectID := tsids[0].ProjectID
 	var metricIDs uint64Sorter
-	tsidsMap := make(map[uint64]*TSID)
 	prefetchedMetricIDs := s.prefetchedMetricIDs.Load().(*uint64set.Set)
 	for i := range tsids {
-		metricID := tsids[i].MetricID
+		tsid := &tsids[i]
+		if tsid.AccountID != accountID || tsid.ProjectID != projectID {
+			logger.Panicf("BUG: unexpected (accountID, projectID) in tsid=%#v; want accountID=%d, projectID=%d", tsid, accountID, projectID)
+		}
+		metricID := tsid.MetricID
 		if prefetchedMetricIDs.Has(metricID) {
 			continue
 		}
 		metricIDs = append(metricIDs, metricID)
-		tsidsMap[metricID] = &tsids[i]
 	}
 	if len(metricIDs) < 500 {
 		// It is cheaper to skip pre-fetching and obtain metricNames inline.
@@ -905,9 +909,11 @@ func (s *Storage) prefetchMetricNames(tsids []TSID) error {
 	idb := s.idb()
 	is := idb.getIndexSearch()
 	defer idb.putIndexSearch(is)
-	for _, metricID := range metricIDs {
-		tsid := tsidsMap[metricID]
-		metricName, err = is.searchMetricName(metricName[:0], metricID, tsid.AccountID, tsid.ProjectID)
+	for loops, metricID := range metricIDs {
+		if loops&(1<<10) == 0 {
+			storagepacelimiter.Search.WaitIfNeeded()
+		}
+		metricName, err = is.searchMetricName(metricName[:0], metricID, accountID, projectID)
 		if err != nil && err != io.EOF {
 			return fmt.Errorf("error in pre-fetching metricName for metricID=%d: %w", metricID, err)
 		}
diff --git a/lib/storagepacelimiter/storagepacelimiter.go b/lib/storagepacelimiter/storagepacelimiter.go
index 1ca5860a10..4eda4d95f9 100644
--- a/lib/storagepacelimiter/storagepacelimiter.go
+++ b/lib/storagepacelimiter/storagepacelimiter.go
@@ -5,7 +5,11 @@ import (
 )
 
 // Search limits the pace of search calls when there is at least a single in-flight assisted merge.
+//
+// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/291
 var Search = pacelimiter.New()
 
 // BigMerges limits the pace for big merges when there is at least a single in-flight small merge.
+//
+// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/648
 var BigMerges = pacelimiter.New()