From 002a1a779bcd60732ccd2f75ecc69f48813e5fc9 Mon Sep 17 00:00:00 2001
From: Weizhen Wang <wangweizhen@pingcap.com>
Date: Sat, 8 Feb 2025 11:07:52 +0800
Subject: [PATCH] datum: remove wrong usage of pool and prealloc the buffer
 (#59331)

close pingcap/tidb#59332
---
 pkg/types/datum.go | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/pkg/types/datum.go b/pkg/types/datum.go
index 3d25f16cce..dd3f56da8e 100644
--- a/pkg/types/datum.go
+++ b/pkg/types/datum.go
@@ -23,7 +23,6 @@ import (
 	"sort"
 	"strconv"
 	"strings"
-	"sync"
 	"time"
 	"unicode/utf8"
 	"unsafe"
@@ -2431,16 +2430,11 @@ func (ds *datumsSorter) Swap(i, j int) {
 	ds.datums[i], ds.datums[j] = ds.datums[j], ds.datums[i]
 }
 
-var strBuilderPool = sync.Pool{New: func() any { return &strings.Builder{} }}
-
 // DatumsToString converts several datums to formatted string.
 func DatumsToString(datums []Datum, handleSpecialValue bool) (string, error) {
 	n := len(datums)
-	builder := strBuilderPool.Get().(*strings.Builder)
-	defer func() {
-		builder.Reset()
-		strBuilderPool.Put(builder)
-	}()
+	builder := &strings.Builder{}
+	builder.Grow(8 * n)
 	if n > 1 {
 		builder.WriteString("(")
 	}