Joining a thread now ensures the underlying OS thread has exited. This is required for safer fork() in multi-threaded processes.
---------
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
The test had an instability issue due to the ordering of the dummy
queue operation and the real wakeup pipe operations. Both primitives
are thread safe but not done atomically as a single update and may
interleave arbitrarily. With the old order of operations this can lead
to an incorrect state where the dummy queue is full but the wakeup
pipe is empty. By swapping the order in clear() I think this can no
longer happen in any possible operation interleaving (famous last
words).
concurrent.futures: The *executor manager thread* now catches
exceptions when adding an item to the *call queue*. During Python
finalization, creating a new thread can now raise RuntimeError. Catch
the exception and call terminate_broken() in this case.
Add test_python_finalization_error() to test_concurrent_futures.
concurrent.futures._ExecutorManagerThread changes:
* terminate_broken() no longer calls shutdown_workers() since the
call queue is no longer working anymore (read and write ends of
the queue pipe are closed).
* terminate_broken() now terminates child processes, not only
wait until they complete.
* _ExecutorManagerThread.terminate_broken() now holds shutdown_lock
to prevent race conditons with ProcessPoolExecutor.submit().
multiprocessing.Queue changes:
* Add _terminate_broken() method.
* _start_thread() sets _thread to None on exception to prevent
leaking "dangling threads" even if the thread was not started
yet.
Fix test_timeout() of test_concurrent_futures.test_wait. Remove the
future which may or may not complete depending if it takes longer
than the timeout ot not. Keep the second future which does not
complete before wait(). Make also the test faster: 0.5 second instead
of 6 seconds, so remove @support.requires_resource('walltime')
decorator.
test_error_at_task_unpickle() and
test_error_during_result_unpickle_in_result_handler() now restore
sys.stderr which is overriden by _raise_error_ignore_stderr().
This fixes issue #105829, https://github.com/python/cpython/issues/105829
Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>
Co-authored-by: Antoine Pitrou <antoine@python.org>
Co-authored-by: Chris Withers <chris@withers.org>
Co-authored-by: Thomas Moreau <thomas.moreau.2010@gmail.com>
Fix a race condition in _ExecutorManagerThread.terminate_broken():
ignore the InvalidStateError on future.set_exception(). It can happen
if the future is cancelled before the caller.
Moreover, test_crash_big_data() now waits explicitly until the
executor completes.
Antoine Pitrou
elfstrom
Victor Stinner
Serhiy Storchaka