Falk Gärtner, also known as proto.beamaz, has released 26-pages PDF document on optimizing Mac OS X 10.3 for realtime performance. Falk is a VJ and uses his Powerbook for realtime VJing with VDMXX. Mixing multiple DV streams in realtime needs maximum performance and if you are operating your computer in a dedicated environment without there is enough slack you can cut from your default install freeing extra CPU cycles for increased performance.
But take care! The document‘s font might harm your vision!