[rules-users] Migrating from 4.0.7 to 5.4.0.Final

Jean-Paul Shemali jshemali at hotmail.com
Wed Jul 4 09:54:02 EDT 2012


Hi again mario,

Yes in my case it would be nice for generated classes to be garbage collected when no longer referenced : for long-lived virtual machines where rules are changed a lot, you really hit the max perm gen quickly enough. 
I guess what you are describing is a production environment where rules are loaded/compiled once in the VM's life (startup time most probably) and that's it. That's not my case, it's rather the reverse in some cases, as specialized users can test their rule sets in the same environment as the production one and choose to release them.

Your option to control JITing space looks like a good way to keep things in check. Would it possible to ensure if we set the space to 0, it actually disables it? That would ensure that everything runs in my calling threads and gets garbage collected right?

Again thanks a mil for your help

> Date: Wed, 4 Jul 2012 06:31:00 -0700
> From: mario.fusco at gmail.com
> To: rules-users at lists.jboss.org
> Subject: Re: [rules-users] Migrating from 4.0.7 to 5.4.0.Final
> 
> Hi again,
> 
> You are looking at the correct branch and I didn't change the MvelConstraint
> class indeed. What I did is to change the ClassGenerator to try to avoid the
> creation of new ClassLoaders (when possible).
> 
> Said that what I don't understand is why you expect the generated classes to
> be garbage collected. They are used to evaluate the constraints in your
> rules, so I don't think they could/should be CG'd anyway. Am I missing
> something?
> 
> Anyway we are realizing that the required PermGen space could be a problem
> especially if you have a big rule base, so I am going to add a configuration
> option that will allow you to define how many space you want to give to
> these JITted constraints. Once the engine will hit this limit it will just
> stop JITting further constraints leaving them run in interpreted mode.
> Hopefully the users will be able to find a good trade-off between
> performances and memory occupation in this way. Does this make sense to you?
> 
> Mario
> 
> --
> View this message in context: http://drools.46999.n3.nabble.com/Migrating-from-4-0-7-to-5-4-0-Final-tp4018215p4018465.html
> Sent from the Drools: User forum mailing list archive at Nabble.com.
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
 		 	   		  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20120704/b649694d/attachment-0001.html 


More information about the rules-users mailing list