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HBase Review Board commented on HBASE-2997: ------------------------------------------- Message from: "Ryan Rawson" <ryano...@gmail.com> ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: http://review.cloudera.org/r/843/#review1230 ----------------------------------------------------------- src/main/java/org/apache/hadoop/hbase/KeyValue.java <http://review.cloudera.org/r/843/#comment4189> key values are only used by 1 thread at a time, so no. and even if they were shared, we'd just result in the current situation - use more cpu than is theoretically necessary. src/main/java/org/apache/hadoop/hbase/KeyValue.java <http://review.cloudera.org/r/843/#comment4190> it actually is worth it... also key values tend to be short lived, but recopying this array out half a dozen times during a scan is pricy according to the profiler. 6% cpu. src/main/java/org/apache/hadoop/hbase/KeyValue.java <http://review.cloudera.org/r/843/#comment4191> in a 64 bit jvm you cannot read a partial long, the updates are atomic. this is part of the spec. also single threaded comment above. - Ryan > Performance fixes - profiler driven > ----------------------------------- > > Key: HBASE-2997 > URL: https://issues.apache.org/jira/browse/HBASE-2997 > Project: HBase > Issue Type: Bug > Affects Versions: 0.89.20100621 > Reporter: ryan rawson > Assignee: ryan rawson > Priority: Critical > Fix For: 0.90.0 > > Attachments: HBASE-2997-1.txt, HBASE-2997-2.txt, HBASE-2997-3.txt, > HBASE-2997-4.txt, HBASE-2997-5.txt > > > while profiling hbase I found a number of slow pieces. Here are fixes for > them. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.