classification
Title: test_thread leaks a core dump on PPC64 AIX 3.x
Type: Stage:
Components: Tests Versions: Python 3.8
process
Status: open Resolution:
Dependencies: Superseder:
Assigned To: Nosy List: Michael.Felt, vstinner, xtreak
Priority: normal Keywords:

Created on 2019-03-12 16:14 by vstinner, last changed 2019-05-21 11:14 by Michael.Felt.

Messages (7)
msg337772 - (view) Author: STINNER Victor (vstinner) * (Python committer) Date: 2019-03-12 16:14
PPC64 AIX 3.x:
https://buildbot.python.org/all/#/builders/10/builds/2224

0:12:47 [160/420/1] test_threading failed (env changed)
...
Ran 158 tests in 12.023s

OK (skipped=1)
Warning -- files was modified by test_threading
  Before: []
  After:  ['core']


I don't know if it's a regression or if it occurred in the past.

Michael: Can you please try to reproduce the issue? Any idea if it's new or not?

You can try to identify which test creates a core dump using:

$ ./python -m test.bisect_cmd --fail-env-changed test_thread -v

The command is supposed to find which test creates the "core" file.
msg337775 - (view) Author: Karthikeyan Singaravelan (xtreak) * (Python triager) Date: 2019-03-12 16:39
See also https://bugs.python.org/issue35828#msg337076 where test_multiprocessing_fork seemed to leave a core dump. Maybe one test core dumps and leaves the report to the other causing env changed?
msg338178 - (view) Author: STINNER Victor (vstinner) * (Python committer) Date: 2019-03-18 09:04
David Edelsohn: Would you mind to have a look at this issue?
msg338975 - (view) Author: Michael Felt (Michael.Felt) * Date: 2019-03-27 16:52
I have looked at this briefly.

I would consider it a regression, or a spurious incident as the bot run before (https://buildbot.python.org/all/#/builders/10/builds/2223) and after (https://buildbot.python.org/all/#/builders/10/builds/2225) do not show this error. It may also be spurious - as there are other users on that bot system and the cause could be a side-effect of something else.

FYI: The error message is something similar to what I see when building using xlc - there is a core dump - but I cannot get a copy of the core dump to evaluate it.

See: https://bugs.python.org/issue35828#msg336134 - where I ask for a hint on how to get the code that reports the ENV change to save/copy a core dump.
msg340391 - (view) Author: STINNER Victor (vstinner) * (Python committer) Date: 2019-04-17 12:02
The same bug is back:
https://buildbot.python.org/all/#/builders/10/builds/2443

Warning -- files was modified by test_threading
  Before: []
  After:  ['core']
msg340395 - (view) Author: Michael Felt (Michael.Felt) * Date: 2019-04-17 13:41
On 17/04/2019 14:02, STINNER Victor wrote:
> STINNER Victor <vstinner@redhat.com> added the comment:
>
> The same bug is back:
> https://buildbot.python.org/all/#/builders/10/builds/2443
>
> Warning -- files was modified by test_threading
>   Before: []
>   After:  ['core']
>
> ----------

What can I do to "copy" the core dump before normal testing removes it?

I have had a similar message regarding the multiprocessing tests, but in
those cases I expect it is the "client" thread complaining about a
"server" thread crash.

>
> _______________________________________
> Python tracker <report@bugs.python.org>
> <https://bugs.python.org/issue36273>
> _______________________________________
>
msg343012 - (view) Author: Michael Felt (Michael.Felt) * Date: 2019-05-21 11:14
Again - how can I get the core (dump) mentioned in the error message. When I force this situation I have several core dumps - not "the one".
History
Date User Action Args
2019-05-21 11:14:43Michael.Feltsetmessages: + msg343012
2019-04-17 13:41:04Michael.Feltsetmessages: + msg340395
2019-04-17 12:02:30vstinnersetmessages: + msg340391
2019-03-27 16:52:20Michael.Feltsetmessages: + msg338975
2019-03-18 09:04:05vstinnersetmessages: + msg338178
2019-03-12 16:39:08xtreaksetnosy: + xtreak
messages: + msg337775
2019-03-12 16:14:04vstinnercreate