How to avoid "Out of Memory" error in Headless WebSphere Integration Developer environment

Diagnosing The Problem

A majority of OutOfMemoryExceptions when using WID are caused by too little heap space for your VM. In this case, you can adjust your maximum heap space with something like -vmargs -Xmx256m, giving your Java applications more space to run in always helps performance. However, there are situations where even with an enormous heap size you can still end up with OutOfMemoryExceptions in your workbench. The reason for this is that your VM is not running out of heap space, but is instead running out of what is known as permSpace . The VM's permSpace is the area of the VM that is used to store data structures and class information (not instances, but the class definitions themselves). In the case of a large enough Java application that may contain tens of thousands of class files that must be loaded, you begin to see how the VM can physically run out of space storing all of that information into the default permSpace . If you have run into a situation where you have run out of permSpace, you will want to adjust your Eclipse shortcut, eclipse.ini , or startup script to include the argument -XX:MaxPermSize=512m ; generally speaking the more memory you give the VM, the better the performance will be. Tuning this value can help you find what works best for your WID install.