With the ioquake3-based World of Padman game, disable SELinux and Audit hadn't even resulted in not even a one frame per second gain for Fedora. However, when using the kernel-debug package, the performance dropped, but the difference would go unnoticed by a gamer.
The Apache web server performance improved by approximately 8% when disabling SELinux and Audit, but when using the kernel-debug there was a huge drop in performance. This NVIDIA ION system could handle over 1,400 requests per second in its stock configuration, but when running the kernel with the debugging options/code in place, it averaged at just over 400 requests per second.
The MP3 encoding performance had little impact on SELinux/Audit and kernel-debug.