From 0cf18a6f636ba46cd8689a38978b8650c6a33454 Mon Sep 17 00:00:00 2001
From: Aliaksandr Valialkin <valyala@victoriametrics.com>
Date: Mon, 15 Jul 2024 23:59:13 +0200
Subject: [PATCH] lib/uint64set: optimize Set.Has() for nil Set - it should be
 inlined now

This makes unnecessary the checkDeleted variable at lib/storage/index_db.go

This is a follow-up for b984f4672e4993f60562a482e18dae86262500fc
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/6342
---
 lib/storage/index_db.go    | 19 +++++++------------
 lib/uint64set/uint64set.go |  4 ++++
 2 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/lib/storage/index_db.go b/lib/storage/index_db.go
index b4078fa7f..e2e9bcc07 100644
--- a/lib/storage/index_db.go
+++ b/lib/storage/index_db.go
@@ -679,7 +679,7 @@ func (is *indexSearch) searchLabelNamesWithFiltersOnDate(qt *querytracer.Tracer,
 	if filter != nil && filter.Len() <= 100e3 {
 		// It is faster to obtain label names by metricIDs from the filter
 		// instead of scanning the inverted index for the matching filters.
-		// This would help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2978
+		// This should help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2978
 		metricIDs := filter.AppendTo(nil)
 		qt.Printf("sort %d metricIDs", len(metricIDs))
 		is.getLabelNamesForMetricIDs(qt, metricIDs, lns, maxLabelNames)
@@ -772,13 +772,12 @@ func (is *indexSearch) getLabelNamesForMetricIDs(qt *querytracer.Tracer, metricI
 	}
 
 	dmis := is.db.s.getDeletedMetricIDs()
-	checkDeleted := dmis.Len() > 0
 
 	var mn MetricName
 	foundLabelNames := 0
 	var buf []byte
 	for _, metricID := range metricIDs {
-		if checkDeleted && dmis.Has(metricID) {
+		if dmis.Has(metricID) {
 			// skip deleted IDs from result
 			continue
 		}
@@ -1033,7 +1032,7 @@ func (is *indexSearch) searchLabelValuesWithFiltersOnDate(qt *querytracer.Tracer
 	if filter != nil && filter.Len() <= 100e3 {
 		// It is faster to obtain label values by metricIDs from the filter
 		// instead of scanning the inverted index for the matching filters.
-		// This would help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2978
+		// This should help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2978
 		metricIDs := filter.AppendTo(nil)
 		qt.Printf("sort %d metricIDs", len(metricIDs))
 		is.getLabelValuesForMetricIDs(qt, lvs, labelName, metricIDs, maxLabelValues)
@@ -1107,13 +1106,12 @@ func (is *indexSearch) getLabelValuesForMetricIDs(qt *querytracer.Tracer, lvs ma
 	}
 
 	dmis := is.db.s.getDeletedMetricIDs()
-	checkDeleted := dmis.Len() > 0
 
 	var mn MetricName
 	foundLabelValues := 0
 	var buf []byte
 	for _, metricID := range metricIDs {
-		if checkDeleted && dmis.Has(metricID) {
+		if dmis.Has(metricID) {
 			// skip deleted IDs from result
 			continue
 		}
@@ -2013,12 +2011,9 @@ func (is *indexSearch) getTSIDByMetricNameNoExtDB(dst *TSID, metricName []byte,
 		if len(tail) > 0 {
 			logger.Panicf("FATAL: unexpected non-empty tail left after unmarshaling TSID: %X", tail)
 		}
-		if dmis.Len() > 0 {
-			// Verify whether the dst is marked as deleted.
-			if dmis.Has(dst.MetricID) {
-				// The dst is deleted. Continue searching.
-				continue
-			}
+		if dmis.Has(dst.MetricID) {
+			// The dst is deleted. Continue searching.
+			continue
 		}
 		// Found valid dst.
 		return true
diff --git a/lib/uint64set/uint64set.go b/lib/uint64set/uint64set.go
index edd8bf042..95fee3ee0 100644
--- a/lib/uint64set/uint64set.go
+++ b/lib/uint64set/uint64set.go
@@ -183,6 +183,10 @@ func (s *Set) Has(x uint64) bool {
 	if s == nil {
 		return false
 	}
+	return s.hasSlow(x)
+}
+
+func (s *Set) hasSlow(x uint64) bool {
 	hi32 := uint32(x >> 32)
 	lo32 := uint32(x)
 	bs := s.buckets