For anyone who is running their own ColdFusion server that wasn't able to attend the session "ColdFusion is Racecar Fast!" i would really recommend checking out their presentation on SlideShare
The guys at Webapper have put together a baseline set of JVM settings & IIS thread settings to get the most out of your ColdFusion Server. Additionally one of the speakers, Mike Brunt (www.cfwhisperer.com), gives some specific info on garbage collection that he posted after the fact and you can check it out here.
If you have additional questions you can follow the speakers on twitter (@IamSigmund(Patrick), @cfwhisperer(Mike), @superex2000(Rex))