golang locking benchmarks

lock_test.go

package main

import (
	"sync"
	"sync/atomic"
	"testing"
)

var v int64

var mutex sync.Mutex

func BenchmarkMutex(b *testing.B) {
	v = 0
	for i := 0; i < b.N; i++ {
		mutex.Lock()
		v++
		mutex.Unlock()
	}
}

var rwMutex sync.RWMutex

func BenchmarkRWMutex_lock(b *testing.B) {
	v = 0
	for i := 0; i < b.N; i++ {
		rwMutex.Lock()
		v++
		rwMutex.Unlock()
	}
}

func BenchmarkRWMutex_rLock(b *testing.B) {
	v = 0
	for i := 0; i < b.N; i++ {
		rwMutex.RLock()
		v++
		rwMutex.RUnlock()
	}
}

func BenchmarkAtomicAdd(b *testing.B) {
	v = 0
	for i := 0; i < b.N; i++ {
		atomic.AddInt64(&v, 1)
	}
}

output

# go test -v -bench=. 
testing: warning: no tests to run
PASS
BenchmarkMutex		50000000	        28.0 ns/op
BenchmarkRWMutex_lock	30000000	        57.0 ns/op
BenchmarkRWMutex_rLock	50000000	        28.0 ns/op
BenchmarkAtomicAdd	100000000	        14.0 ns/op
ok  	tmp/c1v	6.037s