>
I have tried to use the heap dump analyzer off the ISA before, but had
trouble with it never giving me anything useful (probably me not knowing
how to use it correctly).  I found I had a lot of the same objects, but
could never get it to show me the name of the object.  If there were
things to look for from the WAS perspective under java, that might also
help. 
>

Try

WAS http://www.redbooks.ibm.com/abstracts/redp3950.html

HeapAnalyzer and many useful links 
http://www-1.ibm.com/support/docview.wss?uid=swg27006624

EVTK and ISA 
http://www.ibm.com/developerworks/web/library/j-ibmtools2/?S_TACT=105AGX54&ca=dnw-839

You can run HeapAnalyzer without ISA - see the second URL tabs (I use it 
outside ISA for PMRs). Dealing with object leaks is not always 
straightforward, but the general idea is to find the object tree with the 
most storage, click down its hierarchy and find where there is a big drop 
between the size of a level of the tree and the next and that is where you 
often find the leaked objects - see the doc that you can get at via the 
second URL.

If you want to analyse verbosegc output, use ISA and EVTK (or find 
GCCollector or PMAT). This is useful for Java performance analysis as cpu 
problems may be nothing more than the Java Heap is too small or some of 
the command line parameters are set badly e.g. -Xloratio is too big. If 
anyone wants some very simple rules of thumb, ask me.

Regards.

Mike

------------------------------------------------------------------------------------------------------------------
Mike Poil
Java z/OS Level 3 Service
IBM United Kingdom Limited, Hursley Park, Winchester SO21 2JN
Internal: 246824  External: +44 (0)1962 816824 
Java debugging: http://www.ibm.com/developerworks/java/jdk/diagnosis/
------------------------------------------------------------------------------------------------------------------






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