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Hadoop QA commented on HBASE-17471: ----------------------------------- | (/) *{color:green}+1 overall{color}* | \\ \\ || Vote || Subsystem || Runtime || Comment || | {color:blue}0{color} | {color:blue} reexec {color} | {color:blue} 0m 22s {color} | {color:blue} Docker mode activated. {color} | | {color:green}+1{color} | {color:green} hbaseanti {color} | {color:green} 0m 0s {color} | {color:green} Patch does not have any anti-patterns. {color} | | {color:green}+1{color} | {color:green} @author {color} | {color:green} 0m 0s {color} | {color:green} The patch does not contain any @author tags. {color} | | {color:green}+1{color} | {color:green} test4tests {color} | {color:green} 0m 0s {color} | {color:green} The patch appears to include 9 new or modified test files. {color} | | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 3m 3s {color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 0m 35s {color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 0m 45s {color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} mvneclipse {color} | {color:green} 0m 14s {color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} findbugs {color} | {color:green} 1m 41s {color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 0m 27s {color} | {color:green} master passed {color} | | {color:green}+1{color} | {color:green} mvninstall {color} | {color:green} 0m 40s {color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} compile {color} | {color:green} 0m 37s {color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javac {color} | {color:green} 0m 37s {color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} checkstyle {color} | {color:green} 0m 44s {color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} mvneclipse {color} | {color:green} 0m 13s {color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} whitespace {color} | {color:green} 0m 0s {color} | {color:green} The patch has no whitespace issues. {color} | | {color:green}+1{color} | {color:green} hadoopcheck {color} | {color:green} 25m 57s {color} | {color:green} Patch does not cause any errors with Hadoop 2.6.1 2.6.2 2.6.3 2.6.4 2.6.5 2.7.1 2.7.2 2.7.3 or 3.0.0-alpha1. {color} | | {color:green}+1{color} | {color:green} findbugs {color} | {color:green} 1m 49s {color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} javadoc {color} | {color:green} 0m 27s {color} | {color:green} the patch passed {color} | | {color:green}+1{color} | {color:green} unit {color} | {color:green} 83m 31s {color} | {color:green} hbase-server in the patch passed. {color} | | {color:green}+1{color} | {color:green} asflicense {color} | {color:green} 0m 16s {color} | {color:green} The patch does not generate ASF License warnings. {color} | | {color:black}{color} | {color:black} {color} | {color:black} 121m 39s {color} | {color:black} {color} | \\ \\ || Subsystem || Report/Notes || | Docker | Client=1.12.3 Server=1.12.3 Image:yetus/hbase:8d52d23 | | JIRA Patch URL | https://issues.apache.org/jira/secure/attachment/12849230/HBASE-17471.v6.patch | | JIRA Issue | HBASE-17471 | | Optional Tests | asflicense javac javadoc unit findbugs hadoopcheck hbaseanti checkstyle compile | | uname | Linux ffdf64b1c679 3.13.0-105-generic #152-Ubuntu SMP Fri Dec 2 15:37:11 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux | | Build tool | maven | | Personality | /home/jenkins/jenkins-slave/workspace/PreCommit-HBASE-Build/component/dev-support/hbase-personality.sh | | git revision | master / 8aea84d | | Default Java | 1.8.0_121 | | findbugs | v3.0.0 | | Test Results | https://builds.apache.org/job/PreCommit-HBASE-Build/5441/testReport/ | | modules | C: hbase-server U: hbase-server | | Console output | https://builds.apache.org/job/PreCommit-HBASE-Build/5441/console | | Powered by | Apache Yetus 0.3.0 http://yetus.apache.org | This message was automatically generated. > Region Seqid will be out of order in WAL if using mvccPreAssign > --------------------------------------------------------------- > > Key: HBASE-17471 > URL: https://issues.apache.org/jira/browse/HBASE-17471 > Project: HBase > Issue Type: Bug > Components: wal > Affects Versions: 2.0.0, 1.4.0 > Reporter: Allan Yang > Assignee: Allan Yang > Priority: Critical > Attachments: HBASE-17471-duo.patch, HBASE-17471-duo-v1.patch, > HBASE-17471-duo-v2.patch, HBASE-17471.patch, HBASE-17471.tmp, > HBASE-17471.v2.patch, HBASE-17471.v3.patch, HBASE-17471.v4.patch, > HBASE-17471.v5.patch, HBASE-17471.v6.patch > > > mvccPreAssign was brought by HBASE-16698, which truly improved the > performance of writing, especially in ASYNC_WAL scenario. But mvccPreAssign > was only used in {{doMiniBatchMutate}}, not in Increment/Append path. If > Increment/Append and batch put are using against the same region in parallel, > then seqid of the same region may not monotonically increasing in the WAL. > Since one write path acquires mvcc/seqid before append, and the other > acquires in the append/sync consume thread. > The out of order situation can easily reproduced by a simple UT, which was > attached in the attachment. I modified the code to assert on the disorder: > {code} > if(this.highestSequenceIds.containsKey(encodedRegionName)) { > assert highestSequenceIds.get(encodedRegionName) < sequenceid; > } > {code} > I'd like to say, If we allow disorder in WALs, then this is not a issue. > But as far as I know, if {{highestSequenceIds}} is not properly set, some > WALs may not archive to oldWALs correctly. > which I haven't figure out yet is that, will disorder in WAL cause data loss > when recovering from disaster? If so, then it is a big problem need to be > fixed. > I have fix this problem in our costom1.1.x branch, my solution is using > mvccPreAssign everywhere, making it un-configurable. Since mvccPreAssign it > is indeed a better way than assign seqid in the ringbuffer thread while > keeping handlers waiting for it. > If anyone think it is doable, then I will port it to branch-1 and master > branch and upload it. > -- This message was sent by Atlassian JIRA (v6.3.4#6332)