split 与 index 的性能对比

gistfile1.txt

BenchmarkSubStr/split
BenchmarkSubStr/split-4         	11353098	       106 ns/op	      32 B/op	       1 allocs/op
BenchmarkSubStr/index
BenchmarkSubStr/index-4         	187964112	         6.37 ns/op	       0 B/op	       0 allocs/op

str_test.go

package perf

import (
	"strings"
	"testing"
)

func TestSubStr(t *testing.T) {
	t.Run("splitAndGet", func(t *testing.T) {

	})
}

func BenchmarkSubStr(b *testing.B) {
	str := "hello.world"
	split := func(str string) (string, string, bool) {
		parts := strings.Split(str, ".")
		if len(parts) == 1 {
			return str, "", false
		}
		return parts[0], parts[1], true
	}
	index := func(str string) (string, string, bool) {
		pos := strings.IndexByte(str, '.')
		if pos < 0 || pos == len(str)-1 {
			return str, "", false
		}
		a := str[0:pos]
		b := str[pos+1:]
		return a, b, true
	}
	b.Run("split", func(b *testing.B) {
		b.ReportAllocs()
		for i := 0; i < b.N; i++ {
			split(str)
		}
	})
	b.Run("index", func(b *testing.B) {
		b.ReportAllocs()
		for i := 0; i < b.N; i++ {
			_,_,ok:=index(str)
			if ok{
			}
		}
	})
}