Question

我试图运行的想法是这样的：

RUN 3进行计算的过程一旦三个过程之一完成任务立即杀死其他人并继续执行主要任务，我不能让它再运行一秒钟

我尝试过的事情是：通过multiprocessing.manager放置全局变量，但这仍然可以使进程完成循环。引发异常

操作系统：Windows PYTHON：2.7

def f(name):
    Doing = True
    try:
        while Doing:
            print 'DOING',name
            somecodethatmarksDoingAsFalse()
    except Exception as error:
        print 'bye'
        print error
        Doing = False
        return True




if __name__ == '__main__':
    p = multiprocessing.Process(target=f, args=('bob',))
    p2 = multiprocessing.Process(target=f, args=('tom',))
    p.start()
    p2.start()

    p.join()
    p2.join()


    raise Exception('I know Python!')
    sys.exit()

当我将操作标记为false时，我希望能够杀死所有进程，引发异常或以任何方式对一个进程进行计算时以任何方式出现

编辑：这不是重复的，因为它仍然完成执行代码，例如，请求模块仍在发送数据

Answer 1

如果需要立即终止，则可以使用multiprocessing.Event通知父进程有关已满足的条件，并让其立即终止工作进程。对于这种所需的少量同步，管理器进程将过于繁琐。

import os
from datetime import datetime
from multiprocessing import Process, Event


def worker(range_, target, found_event):
    print('{} | pid: {} started'.format(datetime.now(), os.getpid()))
    for x in range_:
        if x == target:
            print('{} | pid: {} found target'.format(
                datetime.now(), os.getpid())
            )
            found_event.set()


if __name__ == "__main__":

    N_WORKERS = 4

    step = int(200e6)
    ranges = [range(x, x + step) # change `range` to `xrange` for Python 2
              for x in range(0, N_WORKERS * step, step)]
    # range(0, 200000000), ..., range(800000000, 1000000000)]
    target = int(150e6)  # <-- worker finding this value triggers massacre
    found_event = Event()

    pool = [Process(target=worker, args=(range_, target, found_event))
            for range_ in ranges]

    for p in pool:
        p.start()

    found_event.wait()  # <- blocks until condition met
    print('{} | terminating processes'.format(datetime.now()))
    for p in pool:
        p.terminate()
    for p in pool:
        p.join()
    print('{} | all processes joined'.format(datetime.now()))

示例输出：

2019-01-17 01:55:33.781884 | pid: 28376 started
2019-01-17 01:55:33.782333 | pid: 28377 started
2019-01-17 01:55:33.782851 | pid: 28378 started
2019-01-17 01:55:33.783484 | pid: 28379 started
2019-01-17 01:55:54.715425 | pid: 28376 found target
2019-01-17 01:55:54.715613 | terminating processes
2019-01-17 01:55:54.716326 | all processes joined

Process finished with exit code 0

满足条件时终止多处理进程

1 个答案: