[ 
https://issues.apache.org/jira/browse/HBASE-15716?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15358006#comment-15358006
 ] 

Hadoop QA commented on HBASE-15716:
-----------------------------------

| (x) *{color:red}-1 overall{color}* |
\\
\\
|| Vote || Subsystem || Runtime || Comment ||
| {color:red}-1{color} | {color:red} patch {color} | {color:red} 0m 3s {color} 
| {color:red} HBASE-15716 does not apply to master. Rebase required? Wrong 
Branch? See https://yetus.apache.org/documentation/0.2.1/precommit-patchnames 
for help. {color} |
\\
\\
|| Subsystem || Report/Notes ||
| JIRA Patch URL | 
https://issues.apache.org/jira/secure/attachment/12815564/15716.implementation.using.ScannerReadPoints.branch-1.patch
 |
| JIRA Issue | HBASE-15716 |
| Console output | 
https://builds.apache.org/job/PreCommit-HBASE-Build/2457/console |
| Powered by | Apache Yetus 0.2.1   http://yetus.apache.org |


This message was automatically generated.



> HRegion#RegionScannerImpl scannerReadPoints synchronization constrains random 
> read
> ----------------------------------------------------------------------------------
>
>                 Key: HBASE-15716
>                 URL: https://issues.apache.org/jira/browse/HBASE-15716
>             Project: HBase
>          Issue Type: Bug
>          Components: Performance
>            Reporter: stack
>            Assignee: stack
>         Attachments: 
> 15716.implementation.using.ScannerReadPoints.branch-1.patch, 
> 15716.prune.synchronizations.patch, 15716.prune.synchronizations.v3.patch, 
> 15716.prune.synchronizations.v4.patch, 15716.prune.synchronizations.v4.patch, 
> 15716.wip.more_to_be_done.patch, HBASE-15716.branch-1.001.patch, 
> HBASE-15716.branch-1.002.patch, HBASE-15716.branch-1.003.patch, 
> HBASE-15716.branch-1.004.patch, ScannerReadPoints.java, Screen Shot 
> 2016-04-26 at 2.05.45 PM.png, Screen Shot 2016-04-26 at 2.06.14 PM.png, 
> Screen Shot 2016-04-26 at 2.07.06 PM.png, Screen Shot 2016-04-26 at 2.25.26 
> PM.png, Screen Shot 2016-04-26 at 6.02.29 PM.png, Screen Shot 2016-04-27 at 
> 9.49.35 AM.png, TestScannerReadPoints.java, before_after.png, 
> current-branch-1.vs.NoSynchronization.vs.Patch.png, hits.png, 
> remove.locks.patch, remove_cslm.patch
>
>
> Here is a [~lhofhansl] special.
> When we construct the region scanner, we get our read point and then store it 
> with the scanner instance in a Region scoped CSLM. This is done under a 
> synchronize on the CSLM.
> This synchronize on a region-scoped Map creating region scanners is the 
> outstanding point of lock contention according to flight recorder (My work 
> load is workload c, random reads).



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to