From 36a9e02c32b3e1ca67b10432138233a5c1b3e070 Mon Sep 17 00:00:00 2001
From: Ti Chi Robot <ti-community-prow-bot@tidb.io>
Date: Wed, 13 Dec 2023 13:40:49 +0800
Subject: [PATCH] statsitics: clear the fmsketch's map correctly (#49379)
 (#49402)

close pingcap/tidb#49381
---
 pkg/statistics/fmsketch.go | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/pkg/statistics/fmsketch.go b/pkg/statistics/fmsketch.go
index 74ee24a922c70..bd0a43d52f08c 100644
--- a/pkg/statistics/fmsketch.go
+++ b/pkg/statistics/fmsketch.go
@@ -213,16 +213,7 @@ func (s *FMSketch) MemoryUsage() (sum int64) {
 }
 
 func (s *FMSketch) reset() {
-	// not use hashset.Clear, it will release all memory and Not conducive to memory reuse.
-	// the size of set is not more than 10000.
-	set := make([]uint64, 0, s.hashset.Count())
-	s.hashset.Iter(func(k uint64, v bool) (stop bool) {
-		set = append(set, k)
-		return false
-	})
-	for _, k := range set {
-		s.hashset.Delete(k)
-	}
+	s.hashset.Clear()
 	s.mask = 0
 	s.maxSize = 0
 }