Summary:
We have seen some rare crash test failures in HyperClockCache, and the source could certainly be a bug fixed in this change, in ClockHandleTable::ConstApplyToEntriesRange. It wasn't properly accounting for the fact that incrementing the acquire counter could be ineffective, due to parallel updates. (When incrementing the acquire counter is ineffective, it is incorrect to then decrement it.)
This change includes some other minor clean-up in HyperClockCache, and adds stats_dump_period_sec with a much lower period to the crash test. This should be the primary caller of ApplyToEntries, in collecting cache entry stats.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10768
Test Plan: haven't been able to reproduce the failure, but should be in a better state (bug fix and improved crash test)
Reviewed By: anand1976
Differential Revision: D40034747
Pulled By: anand1976
fbshipit-source-id: a06fcefe146e17ee35001984445cedcf3b63eb68
Peter Dillinger
b205c6d029