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multiprocessing.Process一旦进程加入，进程所消耗的内存是否会被释放？

我想到的场景大致是这样的：

from multiprocessing import Process
from multiprocessing import Queue
import time
import os

def main():
  tasks = Queue()  
  for task in [1, 18, 1, 2, 5, 2]:
    tasks.put(task)

  num_proc = 3           # this many workers @ each point in time
  procs = []
  for j in range(num_proc):
     p = Process(target = run_q, args = (tasks,))  
     procs.append(p)
     p.start()

  # joines a worker once he's done
  while procs:
    for p in procs:
        if not p.is_alive():
            p.join()        # what happens to the memory allocated by run()?  
            procs.remove(p)
            print p, len(procs)
    time.sleep(1)  

def run_q(task_q):
    while not task_q.empty():  # while's stuff to do, keep working
        task = task_q.get()
        run(task)

def run(x):       # do real work, allocates memory
    print x, os.getpid()
    time.sleep(3*x)


if __name__ == "__main__":
  main()

在实际代码中，长度tasks远远大于 CPU 内核的数量，每个task都是轻量级的，不同的任务占用的 CPU 时间（几分钟到几天）和内存量也大不相同（从花生到几 GB） . 所有这些内存都是 a 本地的run，不需要共享它—​​—所以问题是它是否在 arun返回时释放，和/或在进程加入时释放。

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1 回答 1

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当进程终止时，进程消耗的内存被释放。在您的示例中，这发生在 run_q() 返回时。

于 2012-10-16T23:18:07.423 回答