go语言限制Goroutine数量

package main import ("fmt""runtime""time") func main() {runtime.GOMAXPROCS(runtime.NumCPU())c := make(chan bool, 100)t := time.Tick(time.Second) go func() {for {select {case <-t:watching()}}}() for i := 0; i < 10000000; i++ {c <- truego worker(i, c)} fmt.Println("Done")} func watching() {fmt.Printf("NumGoroutine: %d\n", runtime.NumGoroutine())} func worker(i int, c chan bool) {//fmt.Println("worker", i)time.Sleep(100 * time.Microsecond)<-c}