[ 
https://issues.apache.org/jira/browse/HBASE-14268?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14954684#comment-14954684
 ] 

Y. SREENIVASULU REDDY commented on HBASE-14268:
-----------------------------------------------

compilation is failing on master branch..

{code}
[ERROR] Failed to execute goal 
org.apache.maven.plugins:maven-compiler-plugin:3.2:compile (default-compile) on 
project hbase-common: Compilation failure: Compilation failure:
hbase/hbase/hbase-common/src/main/java/org/apache/hadoop/hbase/util/KeyLocker.java:[51,17]
 cannot find symbol
[ERROR] symbol:   class WeakObjectPool
{code}

> Improve KeyLocker
> -----------------
>
>                 Key: HBASE-14268
>                 URL: https://issues.apache.org/jira/browse/HBASE-14268
>             Project: HBase
>          Issue Type: Improvement
>          Components: util
>            Reporter: Hiroshi Ikeda
>            Assignee: Hiroshi Ikeda
>            Priority: Minor
>             Fix For: 2.0.0, 1.2.0, 1.3.0
>
>         Attachments: 14268-V5.patch, HBASE-14268-V2.patch, 
> HBASE-14268-V3.patch, HBASE-14268-V4.patch, HBASE-14268-V5.patch, 
> HBASE-14268-V5.patch, HBASE-14268-V6.patch, HBASE-14268-V7.patch, 
> HBASE-14268-V7.patch, HBASE-14268-V7.patch, HBASE-14268-V7.patch, 
> HBASE-14268-V7.patch, HBASE-14268-V7.patch, HBASE-14268-V7.patch, 
> HBASE-14268.patch, KeyLockerIncrKeysPerformance.java, 
> KeyLockerPerformance.java, ReferenceTestApp.java
>
>
> 1. In the implementation of {{KeyLocker}} it uses atomic variables inside a 
> synchronized block, which doesn't make sense. Moreover, logic inside the 
> synchronized block is not trivial so that it makes less performance in heavy 
> multi-threaded environment.
> 2. {{KeyLocker}} gives an instance of {{RentrantLock}} which is already 
> locked, but it doesn't follow the contract of {{ReentrantLock}} because you 
> are not allowed to freely invoke lock/unlock methods under that contract. 
> That introduces a potential risk; Whenever you see a variable of the type 
> {{RentrantLock}}, you should pay attention to what the included instance is 
> coming from.



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

Reply via email to