[ https://issues.apache.org/jira/browse/CASSANDRA-19365?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Jakub Zytka updated CASSANDRA-19365: ------------------------------------ Fix Version/s: 5.1 > invalid EstimatedHistogramReservoirSnapshot::getValue values due to race > condition in DecayingEstimatedHistogramReservoir > ------------------------------------------------------------------------------------------------------------------------- > > Key: CASSANDRA-19365 > URL: https://issues.apache.org/jira/browse/CASSANDRA-19365 > Project: Cassandra > Issue Type: Bug > Components: Observability/Metrics > Reporter: Jakub Zytka > Assignee: Jakub Zytka > Priority: Normal > Fix For: 5.1 > > Time Spent: 20m > Remaining Estimate: 0h > > `DecayingEstimatedHistogramReservoir` has a race condition between `update` > and `rescaleIfNeeded`. > A sample which ends up (`update`) in an already scaled decayingBucket > (`rescaleIfNeeded`) may still use a non-scaled weight because `decayLandmark` > has not been updated yet at the moment of `update`. > > The observed consequence was flooding of the cluster with speculative retries > (we happened to hit low-percentile buckets with overweight samples, which > drove p99 below true p50 for a long time). > Please note that despite the manifestation being similar to CASSANDRA-19330, > these are two distinct bugs in their own right. -- This message was sent by Atlassian Jira (v8.20.10#820010) --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org