Issue 34073: asyncio and ProcessPoolExecutor: OSError on loop.close() (original) (raw)

Calling loop.close() on an eventloop configured to use a ProcessPoolExecutor can result in an OSError.

Expected behavior: no exception raised. Actual behavior: an OSError is raised, and following this call, quit() fails to terminate the process gracefully.

Example:

Python 3.8.0a0 (default, Jul 7 2018, 14:35:49) [GCC 7.3.0] on linux Type "help", "copyright", "credits" or "license" for more information.

import asyncio from concurrent.futures import ProcessPoolExecutor import os

loop = asyncio.get_event_loop_policy().new_event_loop() loop.set_default_executor(ProcessPoolExecutor()) future = loop.run_in_executor(None, os.getpid) loop.run_until_complete(future) 24697 loop.close() Exception ignored in: <function ProcessPoolExecutor._start_queue_management_thread..weakref_cb at 0x7f52e7f643f0> Traceback (most recent call last): File "/code/Lib/concurrent/futures/process.py", line 567, in weakref_cb thread_wakeup.wakeup() File "/code/Lib/concurrent/futures/process.py", line 89, in wakeup self._writer.send_bytes(b"") File "/code/Lib/multiprocessing/connection.py", line 183, in send_bytes self._check_closed() File "/code/Lib/multiprocessing/connection.py", line 136, in _check_closed Exception in thread QueueManagerThread: Traceback (most recent call last): File "/code/Lib/threading.py", line 917, in _bootstrap_inner self.run() File "/code/Lib/threading.py", line 865, in run self._target(*self._args, **self._kwargs) File "/code/Lib/concurrent/futures/process.py", line 368, in _queue_management_worker thread_wakeup.clear() File "/code/Lib/concurrent/futures/process.py", line 92, in clear while self._reader.poll(): File "/code/Lib/multiprocessing/connection.py", line 255, in poll self._check_closed() File "/code/Lib/multiprocessing/connection.py", line 136, in _check_closed raise OSError("handle is closed") OSError: handle is closed

raise OSError("handle is closed")

OSError: handle is closed