[
https://issues.apache.org/jira/browse/VELOCITY-595?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12604043#action_12604043
]
Ilkka Priha commented on VELOCITY-595:
--------------------------------------
Wouldn't it be enough to synchronize the loadResource() method only, now
reading from the cache is also synchronized. The benchmark comparing the
effects of this change was run with a duo-core processor, but in heavy duty
servers we may have 8-16 processors where synchronization slows down
performance much more than in simpler cases (couldn't find the test template to
reproduce and test VELOCITY-24).
> ResourceManagerImpl.getResource() causes locking issues
> -------------------------------------------------------
>
> Key: VELOCITY-595
> URL: https://issues.apache.org/jira/browse/VELOCITY-595
> Project: Velocity
> Issue Type: Bug
> Components: Engine
> Affects Versions: 1.5
> Environment: jdk 1.5
> Reporter: Allen Gilliland
>
> The ResourceManagerImpl.getResource() method is synchronized, which makes it
> difficult to share a Velocity Runtime between threads in an environment such
> as a j2ee web application.
> After upgrading Velocity to version 1.5 in Roller and running some
> performance tests I saw a very noticeable decrease in throughput for the
> application. I fired up jconsole and noticed that almost all of my app
> server threads were in a BLOCKED state and were waiting on the
> ResourceManagerImpl.getResource() method.
> In my particular case the difference resulted in a loss of 2/3 of my original
> ops/sec, which is pretty huge. After simply switching Velocity back to the
> 1.4 release and rerunning the test I saw the results I expected.
> I assume this is overactive use of Java synchronization because the developer
> guide suggests that the singleton model is "very appropriate model for use in
> a Servlet 2.2+ compliant web application".
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
