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Heng Chen commented on HBASE-14460: ----------------------------------- {quote} I thought this a little ugly because row could be massive... row should stick around a short time only. {quote} yeah... It is ugly... We should remove the row in map when relates writeQueue be empty for a while.... And the map's value should be a wrapper class which contains a writeQueue and a readPoint.... > [Perf Regression] Merge of MVCC and SequenceId (HBASE-HBASE-8763) slowed > Increments, CheckAndPuts, batch operations > ------------------------------------------------------------------------------------------------------------------- > > Key: HBASE-14460 > URL: https://issues.apache.org/jira/browse/HBASE-14460 > Project: HBase > Issue Type: Bug > Components: Performance > Reporter: stack > Assignee: stack > Priority: Critical > Attachments: 14460.txt, region_lock.png > > > As reported by 鈴木俊裕 up on the mailing list -- see "Performance degradation > between CDH5.3.1(HBase0.98.6) and CDH5.4.5(HBase1.0.0)" -- our unification of > sequenceid and MVCC slows Increments (and other ops) as the mvcc needs to > 'catch up' to our current point before we can read the last Increment value > that we need to update. > We can say that our Increment is just done wrong, we should just be writing > Increments and summing on read, but checkAndPut as well as batching > operations have the same issue. Fix. -- This message was sent by Atlassian JIRA (v6.3.4#6332)