Author josh.r
Recipients carlorosati, davin, josh.r, rhettinger, xiang.zhang, xtreak
Date 2018-08-22.14:10:07
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Message-id <1534947008.8.0.56676864532.issue34410@psf.upfronthosting.co.za>
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Carlo: The point of Xiang's post is that this is only tangentially related to multiprocessing; the real problem is that tee-ing an iterator implemented in Python (of which pool.imap_unordered is just one example) and using the resulting tee-ed iterators in multiple threads (which pool.imap_unordered does implicitly, as there is a thread involved in dispatching work).

The problem is *exposed* by multiprocessing.pool.imap_unordered, but it entirely a problem with itertools.tee, and as Xiang's repro indicates, it can be triggered easily without the complexity of multiprocessing being involved.

I've updated the bug title to reflect this.
History
Date User Action Args
2018-08-22 14:10:08josh.rsetrecipients: + josh.r, rhettinger, davin, xiang.zhang, xtreak, carlorosati
2018-08-22 14:10:08josh.rsetmessageid: <1534947008.8.0.56676864532.issue34410@psf.upfronthosting.co.za>
2018-08-22 14:10:08josh.rlinkissue34410 messages
2018-08-22 14:10:07josh.rcreate