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Lars Hofhansl commented on HBASE-4241: -------------------------------------- I have an (unrealistic) local test scenario that basically "updates" the same row in a state table. VERSIONS is set to 1. In this scenario 1m "updates" produced > 50mb of garbage that is completely avoided with this change. > Optimize flushing of the Store cache for max versions and (new) min versions > ---------------------------------------------------------------------------- > > Key: HBASE-4241 > URL: https://issues.apache.org/jira/browse/HBASE-4241 > Project: HBase > Issue Type: Improvement > Components: regionserver > Affects Versions: 0.92.0 > Reporter: Lars Hofhansl > Assignee: Lars Hofhansl > Attachments: 4241-v2.txt, 4241.txt > > > As discussed with with Jon, there is room for improvement in how the memstore > is flushed to disk. > Currently only expired KVs are pruned before flushing, but we can also prune > versions if we find at least maxVersions versions in the memstore. > The same holds for the new minversion feature: If we find at least minVersion > versions in the store we can remove all further versions that are expired. > Generally we should use the same mechanism here that is used for Compaction. > I.e. StoreScanner. We only need to add a scanner to Memstore that can scan > along the current snapshot. -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira