Python多处理:进程不并行运行

Question

我是python中学习多处理模块的新手。我尝试运行以下简单代码：

import multiprocessing, time
def print_squares(number):
for i in range(number):
print("square of {0} is {1}".format(i , i*i))
time.sleep(0.1)
def print_cubes(number):
for j in range(number):
print("cube of {0} is {1}".format(j, j*j*j))
time.sleep(0.1)
if __name__ == "__main__":
process_1 = multiprocessing.Process(target = print_squares, args = (10,))
process_2 = multiprocessing.Process(target = print_cubes, args = (10,))
process_1.start()
process_2.start()
process_1.join()
process_2.join()

因此，我遇到了以下问题：我预计两个过程将通过并行工作打印混合的立方体和正方形，就像一样

square of 0 is 0
cube of 0 is 0
square of 1 is 1
cube of 1 is 1

等等。我的脚本没有像描述的那样表现，而是打印了：

cube of 0 is 0
cube of 1 is 1
cube of 2 is 8
cube of 3 is 27
cube of 4 is 64
cube of 5 is 125
cube of 6 is 216
cube of 7 is 343
cube of 8 is 512
cube of 9 is 729
square of 0 is 0
square of 1 is 1
square of 2 is 4
square of 3 is 9
square of 4 is 16
square of 5 is 25
square of 6 is 36
square of 7 is 49
square of 8 is 64
square of 9 is 81

很明显，进程并不是并行运行的，第二个进程只有在第一个进程完成后才开始。

此外，当我运行类似的代码，但使用线程而不是进程时，它可以随心所欲地工作。

我使用的是windows 10和python 3.8。我将感谢任何关于如何解决这个问题并使两个过程同时工作的信息，提前感谢！

Answer 1

代码是正确的，应该并行运行。以下是我机器上的输出(linux mint+python3.8(：

square of 0 is 0
cube of 0 is 0
square of 1 is 1

也许有一些stdout缓冲，打印调用在正确的时间发生，但流在最后被刷新，请尝试：

print("cube of {0} is {1}".format(j, j * j * j), flush=True)

或

sys.stdout.flush()