Carlo deWolfe found that one of the big perf problems with Java reflection is that it is constantly doing security checks with the security manager and every get/find request makes a copy of the method/field objects. He had a hack for this, but you'll have to consult him on what it is. The JBoss Reflections project might have it.
I think once this hack is intiated, it is an improvement over Javassist. If you think about it, Java VM has to build up this information anyways... Steve Ebersole wrote: > I ran this same exact comparison before and I seem to recall much > different results. Unfortunately I no longer have that code. This was > part of > http://opensource.atlassian.com/projects/hibernate/browse/HHH-227 > > Can you make sure you "prime" or "warm up" the jvm before you start > taking measurements? > > On Thu, 2010-05-27 at 15:39 +0300, Кирилл Кленский wrote: >> Hi, >> >> My measurements have indicated that there is a performance gain. I have >> measured the time spent in setPropertyValues and getPropertyValues. >> The optimized version was 4 times faster in these methods giving an >> estimated application performance increase of about 3%. >> Optimizing getPropertyValue and setPropertyValue could give 1.5% more >> according to our rough calculations. >> >> Kirill >> >> 26 мая 2010 г. 23:53 пользователь Emmanuel Bernard >> <emman...@hibernate.org>написал: >> >>> Hi, >>> Have you noticed a perf difference in your application with and without the >>> patch? >>> I am wondering if modern VMs have catched up with what Javassist does. >>> >>> On 26 mai 2010, at 18:29, Кирилл Кленский wrote: >>> >>>> 1. I have noticed that >>>> org.hibernate.bytecode.javassist.BulkAccessorFactory.findAccessors(...) >>> is >>>> searching for accessor methods in the optimized entity class only. This >>>> means that the methods from the superclasses are not visible during >>>> BulkAccessor creation unless overridden by child classes. By enhancing >>> the >>>> algorithm to search down the inheritance tree we could avoid creation of >>>> redundant methods which increase the code verbosity a lot. In our case >>>> almost all the entities are inherited from the base classes having the >>>> common entity properties defined, so the reflection optimization does not >>>> work for any of them until we override the inherited methods in all the >>>> child classes. The implementation is trivial, but I have got a ready >>>> prototype if anybody is interested. >>> >> _______________________________________________ >> hibernate-dev mailing list >> hibernate-dev@lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/hibernate-dev > > -- Bill Burke JBoss, a division of Red Hat http://bill.burkecentral.com _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
