Go Int转string几种方式性能测试

Go语言内置int转string至少有3种方式：

fmt.Sprintf("%d",n)

strconv.Itoa(n)

strconv.FormatInt(n,10)

下面针对这3中方式的性能做一下简单的测试：

package gotest

import (
	"fmt"
	"strconv"
	"testing"
)

func BenchmarkSprintf(b *testing.B) {
	n := 10
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		fmt.Sprintf("%d", n)
	}
}

func BenchmarkItoa(b *testing.B) {
	n := 10
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		strconv.Itoa(n)
	}
}

func BenchmarkFormatInt(b *testing.B) {
	n := int64(10)
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		strconv.FormatInt(n, 10)
	}
}

保存文件为int2string_test.go

执行：

go test -v -bench=. int2string_test.go -benchmem

goos: darwin
goarch: amd64
BenchmarkSprintf-8      20000000               114 ns/op              16 B/op          2 allocs/op
BenchmarkItoa-8         200000000                6.33 ns/op            0 B/op          0 allocs/op
BenchmarkFormatInt-8    300000000                4.10 ns/op            0 B/op          0 allocs/op
PASS
ok      command-line-arguments  5.998s

总体来说，strconv.FormatInt()效率最高，fmt.Sprintf()效率最低