Fix a reference issue inside multiprocessing.Pool that caused the pool to remain alive if it was deleted without being closed or terminated explicitly.
multiprocessing.Process.is_alive() now removes the process from the
_children set if the process completed.
The change prevents leaking "dangling" processes.
(cherry picked from commit 2db64823c2)
* bpo-30595: Fix multiprocessing.Queue.get(timeout) (#2027)
multiprocessing.Queue.get() with a timeout now polls its reader in
non-blocking mode if it succeeded to aquire the lock but the acquire
took longer than the timeout.
Co-Authored-By: Grzegorz Grzywacz <grzgrzgrz3@gmail.com>
(cherry picked from commit 1b7863c3b6)
* bpo-30595: Increase test_queue_feeder_donot_stop_onexc() timeout (#2148)
_test_multiprocessing.test_queue_feeder_donot_stop_onexc() now uses a
timeout of 1 second on Queue.get(), instead of 0.1 second, for slow
buildbots.
(cherry picked from commit 8f6eeaf21c)
(cherry picked from commit e42339d3a0)
* Clear potential ref cycle between Process and Process target
Besides Process.join() not being called, this was an indirect cause of bpo-30775.
The threading module already does this.
* Add issue reference.
(cherry picked from commit 79d37ae979)
* bpo-24484: Avoid race condition in multiprocessing cleanup
The finalizer registry can be mutated while inspected by multiprocessing
at process exit.
* Use test.support.start_threads()
* Add Misc/NEWS.
(cherry picked from commit 1eb6c0074d)
* bpo-30414: multiprocesing.Queue._feed do not break from main loop on exc
Queue background running thread was not handling exceptions correctly.
Any exception occurred inside thread (putting unpickable object) cause
feeder to finish running. After that every message put into queue is
silently ignored.
* bpo-30414: multiprocesing.Queue._feed do not break from main loop on exc
Queue background running thread was not handling exceptions correctly.
Any exception occurred inside thread (putting unpickable object) cause
feeder to finish running. After that every message put into queue is
silently ignored..
(cherry picked from commit bc50f03db4)
* bpo-29861: release references to multiprocessing Pool tasks (#743)
* bpo-29861: release references to multiprocessing Pool tasks
Release references to tasks, their arguments and their results as soon
as they are finished, instead of keeping them alive until another task
arrives.
* Comments in test
(cherry picked from commit 8988945cdc)
* Fix Misc/NEWS ?
- backports issue #10845's mitigation of incompatibilities between
the multiprocessing module and directory and zipfile execution
- Multiprocessing on Windows will now automatically skip rerunning top
level __main__.py modules in spawned processes, rather than failing
with AssertionError
In multiprocessing, a pool worker process would die
if the result/error could not be pickled. This could
cause pool methods to hang.
In 3.x this was fixed by 0aa8af79359d (which also added
an error_callback argument to some methods), but the fix
was not back ported.
tzickel
Serhiy Storchaka
Victor Stinner
Antoine Pitrou
Marc Schlaich
Davin Potts
Nick Coghlan
Benjamin Peterson
Richard Oudkerk
Richard Oudkerk
Ezio Melotti
doko@ubuntu.com
Kristján Valur Jónsson
Giampaolo Rodola'
Charles-François Natali
Antoine Pitrou