[ https://issues.apache.org/jira/browse/HBASE-14205?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Sean Busbey updated HBASE-14205: -------------------------------- Component/s: regionserver Coprocessors > RegionCoprocessorHost System.nanoTime() performance bottleneck > -------------------------------------------------------------- > > Key: HBASE-14205 > URL: https://issues.apache.org/jira/browse/HBASE-14205 > Project: HBase > Issue Type: Bug > Components: Coprocessors, Performance, regionserver > Reporter: Jan Van Besien > Assignee: Andrew Purtell > Priority: Critical > Fix For: 2.0.0, 1.2.0, 1.3.0 > > Attachments: HBASE-14205.patch > > > The tracking of execution time of coprocessor methods introduced in > HBASE-11516 introduces 2 calls to System.nanoTime() per coprocessor method > per coprocessor. This is resulting in a serious performance bottleneck in > certain scenarios. > For example consider the scenario where many rows are being ingested (PUT) in > a table which has multiple coprocessors (we have up to 20 coprocessors). This > results in 8 extra calls to System.nanoTime() per coprocessor (prePut, > postPut, postStartRegionOperation and postCloseRegionOperation) which has in > total (i.e. times 20) been seen to result in a 50% increase of execution time. > I think it is generally considered bad practice to measure execution times on > such a small scale (per single operation). Also note that measurements are > taken even for coprocessors that do not even have an actual implementation > for certain operations, making the problem worse. -- This message was sent by Atlassian JIRA (v6.3.4#6332)