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Hudson commented on HBASE-20716: -------------------------------- Results for branch branch-2.1 [build #482 on builds.a.o|https://builds.apache.org/job/HBase%20Nightly/job/branch-2.1/482/]: (x) *{color:red}-1 overall{color}* ---- details (if available): (/) {color:green}+1 general checks{color} -- For more information [see general report|https://builds.apache.org/job/HBase%20Nightly/job/branch-2.1/482//General_Nightly_Build_Report/] (x) {color:red}-1 jdk8 hadoop2 checks{color} -- For more information [see jdk8 (hadoop2) report|https://builds.apache.org/job/HBase%20Nightly/job/branch-2.1/482//JDK8_Nightly_Build_Report_(Hadoop2)/] (x) {color:red}-1 jdk8 hadoop3 checks{color} -- For more information [see jdk8 (hadoop3) report|https://builds.apache.org/job/HBase%20Nightly/job/branch-2.1/482//JDK8_Nightly_Build_Report_(Hadoop3)/] (/) {color:green}+1 source release artifact{color} -- See build output for details. (/) {color:green}+1 client integration test{color} > Unsafe access cleanup > --------------------- > > Key: HBASE-20716 > URL: https://issues.apache.org/jira/browse/HBASE-20716 > Project: HBase > Issue Type: Sub-task > Components: Performance > Reporter: stack > Assignee: Sahil Aggarwal > Priority: Critical > Labels: beginner > Fix For: 3.0.0, 2.2.0, 2.1.1 > > Attachments: HBASE-20716.master.001.patch, > HBASE-20716.master.002.patch, HBASE-20716.master.003.patch, > HBASE-20716.master.004.patch, HBASE-20716.master.005.patch, > HBASE-20716.master.006.patch, HBASE-20716.master.007.patch, > HBASE-20716.master.008.patch, Screen Shot 2018-06-26 at 11.37.49 AM.png > > > We have two means of getting at unsafe; UnsafeAccess and then internal to the > Bytes class. They are effectively doing the same thing. We should have one > avenue to Unsafe only. > Many of our paths to Unsafe via UnsafeAccess traverse flags to check if > access is available, if it is aligned and the order in which words are > written on the machine. Each check costs -- especially if done millions of > times a second -- and on occasion adds bloat in hot code paths. The unsafe > access inside Bytes checks on startup what the machine is capable off and > then does a static assign of the appropriate class-to-use from there on out. > UnsafeAccess does not do this running the checks everytime. Would be good to > have the Bytes behavior pervasive. > The benefit of one access to Unsafe only is plain. The benefits we gain > removing checks will be harder to measure though should be plain when you > disassemble a hot-path; in a (very) rare case, the saved byte codes could be > the difference between inlining or not. -- This message was sent by Atlassian JIRA (v7.6.3#76005)