Golang Random Element Benchmark

README.md

golang-benchmark-random-element

output

$ go test -bench=. -test.benchtime=5s
goos: darwin
goarch: amd64
pkg: github.com/seriousben/benchmark-random-element
benchmarkmodulo10-16       	78412443	        69.0 ns/op	       0 b/op	       0 allocs/op
benchmarkmodulo100-16      	78941438	        70.5 ns/op	       0 b/op	       0 allocs/op
benchmarkmodulo1000-16     	87087330	        69.2 ns/op	       0 b/op	       0 allocs/op
benchmarkmodulo10000-16    	83965998	        70.6 ns/op	       0 b/op	       0 allocs/op
benchmarkrand10-16         	339789382	        18.2 ns/op	       0 b/op	       0 allocs/op
benchmarkrand100-16        	347168102	        18.0 ns/op	       0 b/op	       0 allocs/op
benchmarkrand1000-16       	339647118	        18.0 ns/op	       0 b/op	       0 allocs/op
benchmarkrand10000-16      	332768221	        17.7 ns/op	       0 b/op	       0 allocs/op
pass
ok  	github.com/seriousben/benchmark-random-element	56.117

main_test.go

package main

import (
	"math/rand"
	"testing"
	"time"
)

func doModulo(n int) {
	_ = time.Now().UnixNano() % int64(n)
}

func BenchmarkModulo10(b *testing.B) {
	b.ReportAllocs()
	for i := 0; i < b.N; i++ {
		doModulo(10)
	}
}

func BenchmarkModulo100(b *testing.B) {
	b.ReportAllocs()
	for i := 0; i < b.N; i++ {
		doModulo(100)
	}
}

func BenchmarkModulo1000(b *testing.B) {
	b.ReportAllocs()
	for i := 0; i < b.N; i++ {
		doModulo(1000)
	}
}

func BenchmarkModulo10000(b *testing.B) {
	b.ReportAllocs()
	for i := 0; i < b.N; i++ {
		doModulo(10000)
	}
}

func doRand(n int) {
	_ = rand.Intn(n)
}

func BenchmarkRand10(b *testing.B) {
	b.ReportAllocs()
	for i := 0; i < b.N; i++ {
		doRand(10)
	}
}

func BenchmarkRand100(b *testing.B) {
	b.ReportAllocs()
	for i := 0; i < b.N; i++ {
		doRand(100)
	}
}

func BenchmarkRand1000(b *testing.B) {
	b.ReportAllocs()
	for i := 0; i < b.N; i++ {
		doRand(1000)
	}
}

func BenchmarkRand10000(b *testing.B) {
	b.ReportAllocs()
	for i := 0; i < b.N; i++ {
		doRand(10000)
	}
}