MWS heap dump - what toll to use for analysis

Hi all,

We experienced OutOfMemory with our productive MWS system, and I need to analyze the heap dumps that were generated by the OOM.

I tried mat (Eclipse Memory Analyzer Open Source Project | The Eclipse Foundation), Visualvm (, also jhat (comes with jdk6) all of them with no success.
Mat and jhat are not able to parse the heap dump. Visualvm is doing something, but I waited several hours and it not finished loading the heap dump.

Can somebody direct me to a tool that was used with success?

With thanks,

usually all the tools above work fine. My personal preference is MAT. However two things have to be considered if you are using MAT:

  1. How big is the heap dump (usually the amount allocated to MWS) and is the memory allocated for MAT big enough to parse it. I.e. check your MemoryAnalyzer.ini and -Xmx setting. It should be bigger than the size of the dump.

  2. If your OS is AIX (IBM). Consider using a plug-in for MAT to allow parsing of IBM phd files:

best regards,