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Elliott Clark commented on HBASE-15102: --------------------------------------- That's some great checkstyle math there ( 1 = 33 - 33 ). However the style diff is correct there is one. Findbugs don't seem at all related. Can we get that one check style issue fixed and then I'd be +1 > HeapMemoryTuner can "overtune" memstore size and suddenly drop it into > blocking zone > ------------------------------------------------------------------------------------ > > Key: HBASE-15102 > URL: https://issues.apache.org/jira/browse/HBASE-15102 > Project: HBase > Issue Type: Bug > Components: regionserver > Affects Versions: 2.0.0, 1.2.0, 1.3.0 > Reporter: Ashu Pachauri > Assignee: Ashu Pachauri > Priority: Critical > Fix For: 2.0.0, 1.2.0, 1.3.0 > > Attachments: HBASE-15102-V0.patch, HBASE-15102-V1.patch > > > DefaultHeapMemoryTuner often resets the maximum step size for tuning to 8% of > total heap size. Often, when the size of memstore is to be decreased while > tuning, the 8% tuning can suddenly drop the memstore size below the low water > mark of the previous memstore size (which could potentially be the used size > of the memstore) > This is problematic because suddenly it blocks all the updates by suddenly > causing a situation where memstore used size is above high water mark. This > has a very bad performance impact on an otherwise fine HBase cluster. -- This message was sent by Atlassian JIRA (v6.3.4#6332)