JVM Performance Tuning in real world

Suprisingly, No one have interest in how fast the running application is and where would be bottle neck of performance in it..
I have been involved in maintenance project of E-commerce website such as like Amazon.com for past 4 months.. and have become very suspicious about they, maitenace guys don't try to collect the data of performance... called benchmark...

It's just because the application runs within the limit of maintenace guy's in mind.
and only if their boss get recognized by calling or emailing by the end-users that say application is too slow to use,, they would start analizing the bottle neck or collecting bench mark data...

I was wondering how the other guys think of performance importance of running application from maintenance guys point of view...

well, but I was feeling about collecting perfromance data is right thing and key work to do, I trid to know and evaluate application performance...

java - the Java application launcher
http://java.sun.com/javase/6/docs/technotes/tools/windows/java.html

Garbage Collector Ergonomics
http://java.sun.com/javase/6/docs/technotes/guides/vm/gc-ergonomics.html

Improving Java Application Performance and Scalability by Reducing Garbage Collection Times and Sizing Memory Using JDK 1.4.1
http://developers.sun.com/mobility/midp/articles/garbagecollection2/index.html#4.2

Tuning Garbage Collection with the 5.0 Java[tm] Virtual Machine
http://java.sun.com/performance/reference/whitepapers/5.0_performance.html
http://java.sun.com/docs/hotspot/gc5.0/gc_tuning_5.html

Garbage Collection in the Java HotSpot Virtual Machine(choices and Trade-Offs)
-->PDF on sun.com

some references..
http://blogs.sun.com/dagastine/entry/java_heap_sizing_how_do

http://onesearch.sun.com/search/onesearch/index.jsp?qt=same+heap+size+maximum+minimum&x=0&y=0&charset=utf-8&col=community-all&cs=false&rt=true&reslang=en

Nice discussion
http://forum.java.sun.com/thread.jspa?forumID=37&threadID=5300634

About Permanent Generation memory
http://forum.java.sun.com/thread.jspa?forumID=37&threadID=736264


1.4.1
By default, the young generation uses 2 MB for the Eden, and 64KB for the semi-space. The older generation heap starts from about 5MB and grows up to 44MB. The default permanent generation is 4MB.

launcher.XXMaxPermSize256m
Xms40m
Xmx256m

And I have used TPTP eclipse plugin to collect benchmark data of web application..

these look much like my memo but hope these are useful for some one.