chan_benchmark.go

package main

import (
	"fmt"
	"sync"
	"time"
)

const maxThread = 16

var (
	channel   chan interface{}
	startTime []time.Time
	endTime   []time.Time
	wg        sync.WaitGroup
)

func server(id int) {
	startTime[id] = time.Now()
	for i := 0; i < 1000000; i++ {
		<-channel
	}
}

func client(id int) {
	for i := 0; i < 1000000; i++ {
		channel <- id
	}
	endTime[id] = time.Now()
	wg.Done()
}

func measure(numThreads int) {
	channel = make(chan interface{}, 10000)
	startTime = make([]time.Time, numThreads)
	endTime = make([]time.Time, numThreads)

	for i := 0; i < numThreads; i++ {
		wg.Add(1)
		go server(i)
		go client(i)
	}

	wg.Wait()

	for i := 1; i < numThreads; i++ {
		if startTime[0].After(startTime[i]) {
			startTime[0] = startTime[i]
		}
	}

	for i := 1; i < numThreads; i++ {
		if endTime[0].Before(endTime[i]) {
			endTime[0] = endTime[i]
		}
	}

	ms := endTime[0].Sub(startTime[0]).Seconds() * 1000

	fmt.Printf("chan: %d*1000000 send/recv time in ms: %f (%f nr_of_msg/msec)\n",
		numThreads, ms, float64(numThreads*1000000)/ms)

}

func main() {
	for numThreads := 1; numThreads <= maxThread; numThreads *= 2 {
		measure(numThreads)
	}
}