当我注释掉例子中func myFunc中的打印，cpu会飙升，翻了将近一倍，什么原因啊

[yingjie52]

var sum int32

func myFunc(i interface{}) {
n := i.(int32)
atomic.AddInt32(&sum, n)
fmt.Printf("run with %d\n", n)
}

func demoFunc() {
time.Sleep(1 * time.Millisecond)
//fmt.Println("Hello World!")
}

func main() {
defer ants.Release()

runTimes := 10000000

// 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")

// Use the pool with a function,
// set 10 to the capacity of goroutine pool and 1 second for expired duration.
p, _ := ants.NewPoolWithFunc(1000, func(i interface{}) {
	myFunc(i)
	wg.Done()
})
defer p.Release()
// Submit tasks one by one.
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)

}