Evaluating JVM Heap Dumps

Despite running JVM supposedly being rock-solid and stable I see enough JVM who cant take the load, most likely to non-optimal settings, throwing heap dumps.
A while ago I struggled to open Thread Dumps I can open heap dumps with VisualVM (Version 1.3.7 at the time of writing)

VisualVM

Heap Dump File

Beware, with significant heap dump files (in my sample 700MB) it can take quite a while to open or review the results. Open thread dump list took a good 10 minutes.

Long Processing Times

Remote Glassfish V3.1 and the mystical JMX settings

Once you have any serious sized application running on Glassfish, you need to profile and tune your server settings. A good tool to look under the hood of a running Glassfish is to to connect jconsole (part of JDK) to its JVM. This works without problem for a local Glassfish but when it comes to a remote instance you cant connect to the default Glassfish setup.

Lets look at the default setup

Glassfish Admin Console