Tuning Garbage collection with the 1.4.2 Hotspot JVM

• For many applications garbage collection performance is not significant
• Default collector should be first choice

There are essentially two GC threads running. One is a very lightweight thread which does "little" collections primarily on the Eden (a.k.a. Young) generation of the heap. The other is the Full GC thread which traverses the entire heap when there is not enough memory left to allocate space for objects which get promoted from the Eden to the older generation(s).
If there is a memory leak or inadequate heap allocated, eventually the older generation will start to run out of room causing the Full GC thread to run (nearly) continuously. Since this process "stops the world", Resin won't be able to respond to requests and they'll start to back up.
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