[New-bugs-announce] [issue23051] multiprocessing.pool methods imap() and imap_unordered() cause deadlock

[Alon Diamant]

New submission from Alon Diamant:

When imap() or imap_unordered() are called with the iterable parameter set as a generator function, and when that generator function raises an exception, then the _task_handler thread (running the method _handle_tasks) dies immediately, without causing the other threads to stop and without reporting the exception to the main thread (that one that called imap()).

I saw this issue in Python 2.7.8, 2.7.9 and 3.4.2. Didn't check other versions, but I assume this is a bug in all Python versions since 2.6.

I will be attaching examples that reproduce this issue, as well as patches for both Python 2.7 and Python 3.4.

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components: Library (Lib)
messages: 232643
nosy: advance512
priority: normal
severity: normal
status: open
title: multiprocessing.pool methods imap() and imap_unordered() cause deadlock
type: behavior
versions: Python 2.7, Python 3.4

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue23051>
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