join多进程池类在Python3 ()方法中卡住

Question

正在尝试运行下面的代码。但是，我无法使用join()方法将结果合并到一个字典中。它只是一直在无限期地运行。不确定是我做错了什么，还是某个库还没有针对我的MacBook硅片进行优化。

import random
import time
import multiprocessing as mp
import math

start_time = time.time()
probs = {"cats":0.10,"dogs": 0.80, "bats": 0.10}

calculations = 10000
processors = 8

def f(how_many_times, times):
    for i in range(how_many_times):
        rand_num = random.random()
        total = 0
        for animal, prob in probs.items():
            total += prob
            if total > rand_num:
                times[animal] += 1
                break

if __name__ == '__main__':
    start_time = time.time()
    
    manager = mp.Manager()
    total_times = manager.dict()
    pool = mp.Pool(processors)
    calculations_per_processor = math.floor(calculations/processors)
    for i in range(processors):
        job = pool.apply_async(f, args=(calculations_per_processor, total_times))
    
    pool.close()
    pool.join()
    
    print("--- %s seconds ---" % (time.time() - start_time))

强制退出后，代码给出以下报告：

---------------------------------------------------------------------------
KeyboardInterrupt                         Traceback (most recent call last)
<ipython-input-3-890e4966932e> in <module>
     10 
     11     pool.close()
---> 12     pool.join()
     13 
     14     print("--- %s seconds ---" % (time.time() - start_time))

/opt/anaconda3/lib/python3.8/multiprocessing/pool.py in join(self)
    660         elif self._state not in (CLOSE, TERMINATE):
    661             raise ValueError("In unknown state")
--> 662         self._worker_handler.join()
    663         self._task_handler.join()
    664         self._result_handler.join()

/opt/anaconda3/lib/python3.8/threading.py in join(self, timeout)
   1009 
   1010         if timeout is None:
-> 1011             self._wait_for_tstate_lock()
   1012         else:
   1013             # the behavior of a negative timeout isn't documented, but

/opt/anaconda3/lib/python3.8/threading.py in _wait_for_tstate_lock(self, block, timeout)
   1025         if lock is None:  # already determined that the C code is done
   1026             assert self._is_stopped
-> 1027         elif lock.acquire(block, timeout):
   1028             lock.release()
   1029             self._stop()

KeyboardInterrupt: 

Answer 1

此问题仅出现在Jupyter笔记本电脑中。在终端中运行代码时，join()方法没有问题。不确定如何修复笔记本电脑。我已经尝试卸载anaconda并使用pip3重新安装notebook。但是没有成功