( )⚙ D6844 remotefilelog: replace repack lock to solve race condition

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remotefilelog: replace repack lock to solve race condition
ClosedPublic

Authored by lothiraldan on Sep 12 2019, 9:40 AM.

Details

Summary

2c74337e6483 reduced the probability of race-conditions when starting
background repack and prefetch and we saw the difference in our CI instance
with all failures disappearing except one where one call to waitonrepack seems
to returns too early.

I'm not sure what exactly goes wrong but I realized that while the prefetch
operation uses a standard Mercurial lock, the repack operation is using a
custom lock based on fcntl.flock on available platforms. As extutil.flock
fallback on traditional Mercurial locks on other platforms and the tests are
stable on my laptop, our CI environment and GCC112, I'm sending this patch to
standardize the behavior across environments.

Diff Detail

Repository
rHG Mercurial
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Unit
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Event Timeline

lothiraldan created this revision.Sep 12 2019, 9:40 AM
This revision was not accepted when it landed; it landed in state Needs Review.
This revision was automatically updated to reflect the committed changes.