[issue31990] Pickling deadlocks in thread with python -m

Werner Smidt added the comment: Thanks for going to the trouble, Sara. Curiosity remains, but I'll mark this as closed. -- stage: -> resolved status: open -> closed ___ Python tracker

[issue31990] Pickling deadlocks in thread with python -m

Sara Kelley added the comment: After looking a little more I don't believe the extension is the problem, but it is an easier way to see the problem. When testqueuepickle3 is run as a script you don't see the error. When it is imported as a module, even from another script with valid syntax,

[issue31990] Pickling deadlocks in thread with python -m

Sara Kelley added the comment: https://docs.python.org/3/using/cmdline.html#cmdoption-m The documentation says you must not give a file extension with the module option. Because the extension was given the thread is deadlocking in importlib._bootstrap when trying to acquire the module lock.

[issue31990] Pickling deadlocks in thread with python -m

Werner Smidt added the comment: Sorry for being lacking in providing some OS info. b Opensuse Tumbleweed, Linux kernel 5.8.10-1, Intel system I cannot explain why, but relating to Sara's answer, if you remove the .join() statements at the end, you get the following exception:

[issue31990] Pickling deadlocks in thread with python -m

Sara Kelley added the comment: >python3 -m testqueuepickle3.py >It hangs. I see this hang too. If you only specify the module name it does not hang. python3 -m testqueuepickle3 -- nosy: +serakeri ___ Python tracker

[issue31990] Pickling deadlocks in thread with python -m

Irit Katriel added the comment: Which system are seeing this on? -- ___ Python tracker ___ ___ Python-bugs-list mailing list

[issue31990] Pickling deadlocks in thread with python -m

Werner Smidt added the comment: The condition still stands. if I execute: python3 testqueuepickle3.py Everything is fine. If, however I execute: python3 -m testqueuepickle3.py It hangs. -- versions: +Python 3.8 ___ Python tracker

[issue31990] Pickling deadlocks in thread with python -m

Change by Werner Smidt : -- status: pending -> open Removed file: https://bugs.python.org/file47255/testqueuepickle.py ___ Python tracker ___

[issue31990] Pickling deadlocks in thread with python -m

Irit Katriel added the comment: I don't see the hang on Linux (3.7) or windows (3.10). I think this might be a python 2-only issue. There were problems in Python 2 with importer race conditions, and since you start threads at import time, that could be what was causing what you saw. Python

[issue31990] Pickling deadlocks in thread with python -m

New submission from Werner Smidt : Hi there I recently stumbled on an interesting behaviour. I won't call it an error, because I think it's a mistake I made. BACKGROUND: I want to spawn threads that handle pickled data. This works really well. However, I would