[ 
https://issues.apache.org/jira/browse/HBASE-14268?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14705199#comment-14705199
 ] 

Ted Yu commented on HBASE-14268:
--------------------------------

{code}
117         ReentrantLock lock = getLock(key);
118         purge();
{code}
Do we need to call purge() for every acquireLock() ?

> 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
>         Attachments: HBASE-14268.patch, KeyLockerPerformance.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