[issue40399] Program hangs if process created right after adding object to a Queue

[Delgan]

Delgan <delgan.py at gmail.com> added the comment:

I noticed the bug is reproducible even if the child process does not put object in the queue:




    import multiprocessing 
    import threading 
    import time 

    if __name__ == "__main__": 
      queue = multiprocessing.SimpleQueue() 

      def consume(queue):
        while True:
          print("Consumed:", queue.get())

      thread = threading.Thread(target=consume, args=(queue,))
      thread.start()
      
      for i in range(10000):
        queue.put(i)
        p = multiprocessing.Process(target=lambda: None) 
        p.start() 
        p.join()

        print("Not hanging yet", i)

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue40399>
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