benchmark map versus array retrievals in go

maparraybench_test.go

package maparraybench

import (
	"fmt"
	"os"
	"testing"
)

const (
	itemCount = 100
)

func init() {
	fmt.Fprintf(os.Stderr, "benchmark with %d items\n", itemCount)
}

func BenchmarkMap(b *testing.B) {
	m := make(map[string]int)
	for i := 0; i < itemCount; i++ {
		m[fmt.Sprintf("%x", i)] = i
	}
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		for k, v := range m {
			_ = k
			_ = v
		}
	}
}

func BenchmarkArray(b *testing.B) {
	var a []int
	for i := 0; i < itemCount; i++ {
		a = append(a, i)
	}
	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		for j, v := range a {
			_ = v
			_ = j
		}
	}
}