🍒 5.5+ [Concurrency] set queue width on non apple platforms #39766
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@swift-ci please test |
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@swift-ci please test Windows |
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👍 |
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Windows having weird issues: |
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@swift-ci please test Windows |
ktoso
changed the title
DougGregor
approved these changes
Oct 15, 2021
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Description: To avoid thread explosions, i.e. thread growth to the hardcoded number of 255 when tasks are blocked on Linux (and other non apple platforms), and in order to get the same behavior as Swift Concurrency has on Darwin (and back deployment), we must set the global queue width as we set it up for swift concurrency. Without this, when tasks block for even short bursts, we end up with many many threads on Linux systems. The fix sets the width, same as we do on back deployment and gets us consistent behavior across platforms, and no thread explosions.
Risk: Low, affects only non-apple platforms
Review by: @DougGregor @rjmccall @tomerd
Testing: verified manually using example applications;
Original PR: #39764 and the previous one #39742
Radar: rdar://79907041