I am working for a customer, doing some performance review for their java application and tuning glassfish as well.
They use linux 64 bits (kernel 2.6.18 SMP), glassfish v2 u2 and JDK 5 u12. At some point I needed to generate a heap dump to better understand the object allocation and if possible some hints as to where to look for optimization for the application.
Now the big problem, I could not...
on Oct 1, 2008
There is a wiki site at Sun, about HotSpot Internals, with valuable information to people who wants to better understand HotSpot but don't have the proper time to dedicate to such good reading of HotSpot source code.
As an example, there are tips about how to optimize Java code to the best and how HostSpot sees it
on Aug 20, 2008
You can see my presentation about Tools and Tips to Diagnose Performance Issues on-line or download it.
It was great, because the room was almost full, people keep taking pictures, looks like the topic was interesting.
Some people asked questions at the end, where I want to answer here, to a broad audience.
All of them are hard questions. As there is no recipe to answer them.
Q.1) What is...
on Jun 25, 2008
week I am heading up to the northern hemisphere to join a
crowd of Java professionals and enthusiasts to participate to Jazoon
Tools and Tips to Diagnose
Performance Issues is the session I am going to
share tips and tools to help diagnose performance issues on Java
applications. Some of them are heap and thread dump analysys,
on Jun 13, 2008
If I ask someone else what a Jazooner is, probably they could think it is a character from Klingon, right ?
But for the people at Zurich organizing such a java international conference, it is a place for learning, sharing, talking about Java and meet good professionals. I am proud to be part of the show.
My session Tools and Tips to Diagnose Performance Issues, is scheduled at June, 24 at 5:30pm...
on Apr 12, 2008
A customer asked me to verify how many threads is possible to run concurrently at any java vm on the server. I did some search at the customer support site, but was not lucky to found any proper test utility, so I created one and hope it be useful to someone else.
At first I thought it was just a matter of a for loop, create and start the thread inside the loop. Easy task.
As I ran the test...
on May 23, 2007