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

[JP Chemali]

Hi all,

I'm currently in the process of migrating an application using drools 4.0.7
to 5.4.0.Final and I've stumbled into a few issues with the new version that
I find disturbing: 

- Our unit tests failed because the JVM ran out of perm gen space, which
looks odd as in 4.0.7 we've had quite a margin to start with.
- Doing several Yourkit analysis, I finally find classloading leaks:   
  * *org.drools.rule.builder.dialect.asm.ClassGenerator.EMPTY_METHOD_BODY*
is a static instance which will hold to the last instance of
InternalClassLoader created
  * *org.drools.rule.constraint.MvelConstraint* uses an ExecutorHolder that
spawns daemon threads and keeps them in a pool. Problem is these threads
create class loaders, and can only be garbage collected when the thread
dies, meaning never in my case...
- I've quick fixed both issues, the second one by simply disabling the
thread pool.
- Once this is done, the perm gen behaves correctly, but the execution times
are 2-3 times slower on very large set of rules (~1000). Looking at Yourkit
analysis again, I see that the number of classes generated and the perm gen
consumption is about 3 times higher in 5.4.0.Final. I honestly don't know
how to address this.

I've tried to find some other posts concerning these issues, to no avail. I
don't see any work around this, short of code changes, and for reducing the
number of generated classes I simply have no idea.

Please correct me if I am wrong, any help would be greatly appreciated

--
View this message in context: http://drools.46999.n3.nabble.com/Migrating-from-4-0-7-to-5-4-0-Final-tp4018215.html
Sent from the Drools: User forum mailing list archive at Nabble.com.