Golang benchmark test

argbench_test.go

package argbench

import (
	"testing"
)

// n limits the size of the constructed arrays, to prevent the benchmarks from
// measuring memory bandwidth instead of performance.
const n = 1024

func BenchmarkAppendInline(b *testing.B) {
	for i := 0; i < b.N; i++ {
		a := make([]int, 0, n)
		for j := 0; j < n; j++ {
			a = append(a, i)
		}
	}
}

func appendFunc(a []int, i int) []int {
	return append(a, i)
}

func BenchmarkAppendCall(b *testing.B) {
	for i := 0; i < b.N; i++ {
		a := make([]int, 0, n)
		for j := 0; j < n; j++ {
			a = appendFunc(a, i)
		}
	}
}

func appendFuncVargs(a []int, is ...int) []int {
	return append(a, is...)
}

func BenchmarkAppendCallVargs(b *testing.B) {
	for i := 0; i < b.N; i++ {
		a := make([]int, 0, n)
		for j := 0; j < n; j++ {
			a = appendFuncVargs(a, i)
		}
	}
}

func BenchmarkAppendCallVargs2(b *testing.B) {
	for i := 0; i < b.N; i += 2 {
		a := make([]int, 0, n)
		for j := 0; j < n; j++ {
			a = appendFuncVargs(a, i, i+1)
		}
	}
}