Need help with bat parameters

Hi!
I need some help with configuring the run.bat file, since we're running the server on 8gb RAM, no players online, no other plugin than dynmap, and during a fullrender we're still running out of memory.
Therefore I'd need some examples and explanations on what parameters we can run it on. Garbage collecting and such.

Currently we're having the standard, this:

Code:

@ECHO OFF
"%ProgramFiles%\Java\jre6\bin\java.exe" -Xms3G -Xmx8G -jar "%~dp0craftbukkit-1.0.0-SNAPSHOT.jar"

PAUSE

Now I know that i've seen some thread that discussed this, but I couldn't find it again, I think that @Afforess wrote a lot in it.