pytho线程信号量

pytho线程信号量

import threading,time
def going(num,sleep_time):
    semaphore.acquire()#启动允许执行
    print("gonging is %s"%num)
    time.sleep(sleep_time)
    semaphore.release()#释放
if __name__=="__main__":
    semaphore  = threading.BoundedSemaphore(5) #最多允许5个线程同时运行
    for i in range(20):
        t = threading.Thread(target=going,args=(i,1))
        t.start()