You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@velocity.apache.org by "Malcolm Edgar (JIRA)" <de...@velocity.apache.org> on 2008/07/22 14:26:31 UTC

[jira] Commented: (VELOCITY-606) Velocity 1.5 performance bottlenecks

    [ https://issues.apache.org/jira/browse/VELOCITY-606?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12615604#action_12615604 ] 

Malcolm Edgar commented on VELOCITY-606:
----------------------------------------

Very interesting, always keen to see how we can improve Velocities performance.

With regard to the alternative classes, I believe supporting JDK .14 is still very important in Velocity so I would be keen to use alternative 1.4 compatible implementations:

EDU.oswego.cs.dl.util.concurrent.ConcurrentReaderHashMap

and

org.apache.commons.lang.text.StrBuilder

regards Malcolm Edgar




> Velocity 1.5 performance bottlenecks
> ------------------------------------
>
>                 Key: VELOCITY-606
>                 URL: https://issues.apache.org/jira/browse/VELOCITY-606
>             Project: Velocity
>          Issue Type: Bug
>          Components: Engine
>    Affects Versions: 1.5
>         Environment: Win XP, 1 Gb, single core, Maven 2, JUnitPerf, JRat, cached Velocity templates with a ClassLoader
>            Reporter: Jarkko Viinamäki
>         Attachments: velocity-1.5-250-threads-loadtest.PNG, velocity-1.5-50-threads-loadtest.PNG
>
>
> I did some quite extensive profiling to identify performance bottlenecks in Velocity 1.5.
> Using Maven 2, JUnitPerf and JRat I was able to identify these methods as top bottlenecks:
> org.apache.velocity.util.introspection	ClassMap - findMethod(String,Object[])
> org.apache.velocity.util.introspection	IntrospectorBase - getMethod(Class,String,Object[])
> org.apache.velocity.runtime.parser.node	SimpleNode - literal()
> org.apache.velocity.runtime.parser.node	SimpleNode - render(InternalContextAdapter,Writer)
> org.apache.commons.collections	ExtendedProperties - getBoolean(String,boolean)
> org.apache.velocity.runtime.parser.node	ASTReference - render(InternalContextAdapter,Writer)
> The first two eat over 50% of the CPU with many threads. See attached screenshots.
> Interestingly enough the synchronized
> org.apache.velocity.runtime	RuntimeInstance	getTemplate(String,String)
> isn't a big problem when templates are cached. However, if all resources are not cached it becomes a serious performance bottleneck. ResourceCacheImpl also uses a synchronized map which slows things down.
> I think these bottlenecks could be at least made less worse by reducing synchronization by using ConcurrentHashMap and StringBuilder that ship with JDK 1.5. I'm investigating what kind of benefits could be achieved with those.

-- 
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: dev-unsubscribe@velocity.apache.org
For additional commands, e-mail: dev-help@velocity.apache.org