Comparsion of channels ws file per goroutine

test.go

package file_watcher

import (
	"fmt"
	"io"
	"log"
	"os"
	"strings"
	"sync"
	"testing"
)

func filePerRouting() {
	wg := sync.WaitGroup{}

	t := log.Logger{}

	for i := 0; i < 1000; i++ {
		wg.Add(1)
		go func(number int) {
			f, err := os.OpenFile("/tmp/test.file.log", os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0644)
			if err != nil {
				t.Fatal(err)
			}

			for j := 0; j < 1000; j++ {
				r := strings.NewReader(fmt.Sprintf("goroutine: %d, loop: %d\n", number, j))
				_, err = io.Copy(f, r)
				if err != nil {
					t.Fatal(err)
				}
			}
			err = f.Close()
			if err != nil {
				t.Fatal(f)
			}
			wg.Done()
		}(i)
	}
	wg.Wait()
}

func withChanel() {
	t := log.Logger{}
	wg := sync.WaitGroup{}

	ch := make(chan string, 0)

	wg.Add(1)
	go func(input chan string) {
		f, err := os.OpenFile("/tmp/test.file.log", os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0644)
		if err != nil {
			t.Fatal(err)
		}

		for x := range input {
			r := strings.NewReader(x)
			_, err = io.Copy(f, r)
			if err != nil {
				t.Fatal(err)
			}
		}

		err = f.Close()
		if err != nil {
			t.Fatal(f)
		}

		wg.Done()
	}(ch)

	tokens := make(chan bool, 1000)

	for i := 0; i < 1000; i++ {
		wg.Add(1)
		go func(number int, c chan string) {

			for j := 0; j < 1000; j++ {
				c <- fmt.Sprintf("goroutine: %d, loop: %d\n", number, j)
			}

			// signaling about exit
			tokens <- true
			wg.Done()
		}(i, ch)
	}

	// closing channel after all goroutins exit
	for i := 0; i < 1000; i++ {
		<-tokens
	}
	close(ch)
	wg.Wait()
}

func BenchmarkFilePerRoutine(b *testing.B) {
	for i := 0; i < b.N; i++ {
		filePerRouting()
	}

}

func BenchmarkWithChannel(b *testing.B) {
	for i := 0; i < b.N; i++ {
		withChanel()
	}

}


/*
1	1334103459 ns/op
1	1743324112 ns/op

*/