Runnig a large fusion app, we enabled -verbose to look at the classes that were loaded. It reports that 34037 classes were loaded and 1617 classes were unloaded.

NMT summary for the same period of time reports
- Class (reserved=21983KB, committed=21983KB)
                            (classes #28215)
                            (malloc=21983KB, #32777)

The count of -verbose and the NMT summary are after forcing 3 full GCs to unload all classes and have a safepoint for NMT.

I have not been able to replicate this with a smaller (or accessible) app.