PHOENIX-7825 ConcurrentMutationsIT make MyClock.shouldAdvance volatile#2442
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apurtell wants to merge 1 commit intoapache:masterfrom
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PHOENIX-7825 ConcurrentMutationsIT make MyClock.shouldAdvance volatile#2442apurtell wants to merge 1 commit intoapache:masterfrom
apurtell wants to merge 1 commit intoapache:masterfrom
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ConcurrentMutationsITinstalls a customEnvironmentEdge, and the test thread callssetAdvance(false)to freeze time so two mutations share a timestamp. However,MyClock.shouldAdvanceis not volatile, so the JMM does not require regionserver handler threads in the same JVM to observe the freeze, and in practice they keep advancing time, causing mutations expected to share a timestamp to diverge and producing non-deterministic index-scrutiny results, with the sharedParallelStatsDisabledmini-cluster amplifying the race.