IBM pattern modeling and analysis tool for Java garbage collector

IBM® provides an excellent tool called the IBM Pattern Modeling and Analysis Tool for Java™ Garbage Collector (pmat) to help you visualize the GC statistics such as pause times, amount of space requested, etc.

The pmat is available for download from IBM's alphaworks website at IBM developerWorks. The download page contains excellent information about using the tool for analysis and troubleshooting.