[seam-dev] InitialContext performance issues

[Shane Bryzak]

Jay Balunas wrote:
> I have been looking more into the InitialContext and some of the 
> performance issues surrounding it.
>
> There are really a couple of things to look at.  One is how the 
> InitialContext is created, and manged, and the other broad category is 
> how often and what items are looked up?  I have investigated the 
> first, and have begun investigating the second.
>
> InitialContext creation and management
> ------------------------------------------------
> The only location were seam creates and manages the InitialContext is 
> the "org.jboss.seam.util.Naming" class (see: 
> http://fisheye.jboss.org/browse/Seam/trunk/src/main/org/jboss/seam/util/Naming.java?r=5444 
> ). 
>
> The properties are set in one location and done only once in the 
> initialization of seam (see: 
> http://fisheye.jboss.org/browse/Seam/trunk/src/main/org/jboss/seam/init/Initialization.java?r=9116#l915 
> ).
>
> I see two issues here - one is creating the initial context every 
> single time it is needed, and the other is processing/checking the 
> properties every time it is called.
>
> The first issue would require some caching mechanism or logic for 
> reuse.  I am not an expert on when it makes sense to reuse an instance 
> of the InitialContext, and when we need to get it fresh.  I can say 
> that we currently use they exact same properties to initialize it and 
> those are set during Seam initialization and do not appear to ever 
> change once created.  Is there a way to cache and optimize this 
> instantiation?
>
> The second issue is that we do a certain amount of processing every 
> time the context is requested, this could be optimized.  Currently I 
> see a few blocked threads on the "props.size()" call in the Naming 
> class which is a synchronized method on the Hashtable.  This could 
> easily be avoided.  Although we need to maintain the logic that if the 
> property list is empty we continue to call "new InitialContext()" and 
> not pass in the properties object.  This is because the first thing 
> the InitialContext constructor does with a properties object is clone 
> it which can be costly.  I have attached a patch that implements these 
> changes for review.
>
> Another item I noticed is that the only place (excluding some test 
> code) that does not use "Naming.getInitialContext()" is the 
> "org.jboss.seam.remoting.messaging.JBossConnectionProvider".  It using 
> the "new InitialContext()" directly.  Shane - is there a reason for 
> this? 
That class is gone now, I removed it recently.
>
> I'll write up my findings on the lookup usage asap.
>
> Thanks,
> Jay
> -- 
> blog: http://in.relation.to/Bloggers/Jay
> ------------------------------------------------------------------------
>
> _______________________________________________
> seam-dev mailing list
> seam-dev at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/seam-dev