bench_results.txt

go test -bench=. itoa_test.go
goos: darwin
goarch: amd64
BenchmarkFmtSprintf-4    	 2000000	       938 ns/op
BenchmarkStrconvItoa-4   	 5000000	       253 ns/op
PASS
ok  	command-line-arguments	4.335s

itoa_test.go

package main

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

var testcases = []int{123, 9, 987654321, 101, 512, 22223333}

func BenchmarkFmtSprintf(b *testing.B) {
	for i := 0; i < b.N; i++ {
		for _, val := range testcases {
			fmt.Sprintf("%d", val)
		}
	}
}

func BenchmarkStrconvItoa(b *testing.B) {
	for i := 0; i < b.N; i++ {
		for _, val := range testcases {
			strconv.Itoa(val)
		}
	}
}