I was testing the new cfs scheduler  in the past few weeks and has
found this site:
there are prebuilt kernels for FC6/F7 (F7 kernels should also work on
rawhide) with the cfs scheduler patched in. If anyone wants to play with
new stuff he can go ahead and test them and share the results. CFS
should make it into mainline in 2.6.23.
Your system should fell more responsive under load when using this kernels.