multiprocessing用例

from multiprocessing import Pool
import time,random


def fun(x):

    print(str(x))
    time.sleep(random.randrange(3, 5))
    
if __name__=="__main__":
    pool = Pool(8)
    for i in range(80):
        pool.apply_async(func=fun,args=(i,))
        print('-------------')
    print('go')
    pool.close()
    print('close')
    pool.join()
    print('ok')

for i in range(5):
        s = multiprocessing.Process(target=main,args=('a',))
        s.start()
        l.append(s)
    for i in l:  无法控制进程数量 而Pool可以.
        i.join()