Fix a race condition in the object store logger #1328
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The Object Store Logger had a race condition in `post_close` where the workers could be shut down before all files were enqueued, due to the same flag being used multiple times. Fixed by adding a second flag to trigger shutdown of the enquing thread that is seperate from the flag used to shutdown the worker pool. Did not add a new test case to verify the "fix", as it is impossible to deterministically trigger this race condition via the public API. Closes https://mosaicml.atlassian.net/browse/CO-638
ravi-mosaicml
requested review from
moinnadeem,
mvpatel2000,
milocress,
ishanashastri and
bandish-shah
milocress
approved these changes
Aug 1, 2022
jbloxham
approved these changes
Aug 1, 2022
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The Object Store Logger had a race condition in
post_closewhere the workers could be shut down before all files were enqueued, due to the same flag being used multiple times. Specifically, if all workers saw an empty queue after the shutdown flag was set while the enqueueing thread was sleeping, then the worker pool would shut down, even if there were objects left to enqueue.Fixed by adding a second flag to trigger shutdown of the enquing thread that is seperate from the flag used to shutdown the worker pool.
Did not add a new test case to verify the "fix", as it is impossible to deterministically trigger this race condition via the public API.
Closes https://mosaicml.atlassian.net/browse/CO-638