In NetBeans IDE 7.2.1, here's what you need to fill out before you can begin profiling an application's memory usage:
That's quite a bit of work you need to do, and understanding you need to have, before you can begin your memory profiling. In NetBeans IDE 7.3, that's been improved, such that getting started with memory profiling is much easier:
In other words, what you see above is the same as what you see when you start doing CPU profiling, a simple screen that lets you get started immediately.
Just click the Quick (sampled) memory profiling option, the application will automatically be deployed, and you can immediately begin analyzing the information that the Profiler returns. You're getting sampled memory results with no overhead in setting up the profiling environment.
This is great for identifying leaks, because you can immediately see live instances that shouldn't be allocated or the number of live instances increasing in time.
The next step is to take a heap dump, to see which objects are preventing the instances from being GCed. Or you can switch to instrumented memory profiling to see from where in the code the instances are being allocated.
Further new features in the NetBeans Profiler in NetBeans IDE 7.3:
Thanks to Jiri Sedlacek for help with this info.