Go ants库使用

package main

import (
	"fmt"
	"sync"
	"sync/atomic"
	"time"

	"github.com/panjf2000/ants/v2"
)

var sum int32

func myFunc(i interface{}) int32 {
	n := i.(int32)
	atomic.AddInt32(&sum, n)
	return n
}

func demoFunc() {
	time.Sleep(10 * time.Millisecond)
	fmt.Println("Hello World!")
}

func main() {
  // ants库中定义了一个默认的池，默认容量为MaxInt32, 使用的使用可以不用再New, 但是默认池也需要Release()
	defer ants.Release()

	runTimes := 1000

	// Use the common pool.
	var wg sync.WaitGroup
	syncCalculateSum := func() {
		demoFunc()
		wg.Done()
	}
	for i := 0; i < runTimes; i++ {
		wg.Add(1)
		_ = ants.Submit(syncCalculateSum)
	}
	wg.Wait()
	fmt.Printf("running goroutines: %d\n", ants.Running())
	fmt.Printf("finish all tasks.\n")

	// 控制goroutine池的容量
	p, _ := ants.NewPoolWithFunc(10, func(i interface{}) {
		// 获取返回结果
		ret := myFunc(i)
		fmt.Printf("result= %d\n", ret)
		wg.Done()
	})
	defer p.Release()
	// 提交任务
	for i := 0; i < runTimes; i++ {
		wg.Add(1)
		_ = p.Invoke(int32(i))
	}
	wg.Wait()
	fmt.Printf("running goroutines: %d\n", p.Running())
	fmt.Printf("finish all tasks, result is %d\n", sum)
}

....
running goroutines: 1000
finish all tasks.
....
running goroutines: 10
finish all tasks, result is 499500
Exiting.
....