python多进程编程

Posted 2021-02-10 愤怒中的小草

""""
import os
import time
#fork只用于linux中
pid = os.fork()
print("hello")
if pid == 0:
    print("子进程{},父进程是{}".format(os.getpid(),os.getppid()))
else:
    print("父进程是{}".format(os.getppid()))

#加这个的目的是当父进程关闭的时候关闭子进程
time.sleep(2)
"""
from concurrent.futures import ProcessPoolExecutor
import multiprocessing

#多进程编程
import time

def get_html(n):
    time.sleep(n)
    print("sub_process")
    return n

if __name__ == "__main__":
    #process = multiprocessing.Process(target=get_html,args=(2,))
    #process.start()
    #process.join()
    #print("main process")

    #进程池
    pool = multiprocessing.Pool(multiprocessing.cpu_count())
    #result = pool.apply_async(get_html,args=(3,))

    #等待所有任务完成加入
    #pool.close()
    #pool.join()
    #print(result.get())

    #imap
    #for result in pool.imap(get_html,[1,5,3]):
    #    print("{} sleep success".format(result))

    for result in pool.imap_unordered(get_html,[1,5,3]):
        print("{} sleep success".format(result))