python - 如何随后运行两个并行进程？

Question

我想确保以下两个并行过程相继实现。特别是，我希望先实现十个 f 功能，然后在完成该部分后，再实现十个 g 功能。有谁知道我应该如何修改我的代码？

from multiprocessing import Process
import time
import random

wait_low = 0.1
wait_high = 15

def f(i):
    time.sleep(random.uniform(wait_low, wait_high))
    print 'hello'+str(i)

def g(i):
    time.sleep(random.uniform(wait_low, wait_high))
    print 'hey'+str(i)


if __name__ == '__main__':
    for j in range(10):
        p = Process(target=f, args=(j,))
        p.start()
    p.join()

    print "switch"

    # comment
    for j in range(10):
        q = Process(target=g, args=(j,))
        q.start()
    q.join()

    time.sleep(5)

    print "I'm done"

我得到的结果是:

hello2
hello0
hello1
hello5
hello6
hello8
hello3
hello7
hello9
switch
hey6
hey3
hello4
hey9
hey8
I'm done
hey2
hey0
hey1
hey5
hey7
hey4

非常感谢!

Answer 1

所有 f 和 g 都需要连接。

if __name__ == '__main__':
    fs = []
    for j in range(10):
        p = Process(target=f, args=(j,))
        p.start()
        fs.append(p)

    for f in fs:
        f.join()

    print "switch"

    # comment
    gs = []
    for j in range(10):
        q = Process(target=g, args=(j,))
        q.start()
        gs.append(q)

    for g in gs:
        g.join()

    print "I'm done"

输出:

hello2
hello8
hello5
hello6
hello9
hello1
hello4
hello3
hello7
hello0
switch
hey0
hey7
hey2
hey8
hey4
hey3
hey1
hey9
hey5
hey6
I'm done