Earlier this week there were Fedora 15 vs. Ubuntu 11.04 benchmarks looking at the overall system performance as well as the power consumption. Both of these Linux distributions had performed close to one another, as is expected considering the similarities in their kernel and other packages, but there were some discrepancies in the disk tests. Speculations in the forums were that some of the performance differences might be attributed to SELinux, so here are some tests seeing the performance impact of SELinux on Fedora 15.
Security-Enhanced Linux (SELinux) continues to be enabled by default on Fedora installations. Fortunately, compared to the early Fedora (Core) days, SELinux is much less problematic now than it was in years past. Two years ago, there were SELinux benchmarks on Phoronix, but here is an updated look at where things stand today.
With Fedora 15, the default SELinux settings is the enforcing mode (the SELinux security policy is enabled) while the other options are permissive (SELinux just prints warnings instead of enforcing the policy), or to outright disable SELinux whereby there is no security protection. There are also the targeted and strict types of SELinux, with the default being the targeted mode. In this article are benchmarks of the SELinux enforcing and permissive modes, along with this Linux feature bring outright disabled.
To look for the greatest impact, a low-power netbook was used for testing. This netbook was the Samsung NC10 with an Intel Atom N270 CPU, i945 graphics, 2GB of system memory, and a 32GB OCZ Core Series SSD. A clean install of Fedora 15 (i686) with the Linux 2.6.38 kernel, GNOME Shell 3.0.1, X Server 1.10.1, xf86-video-intel 2.14.0, Mesa 7.11-devel, GCC 4.6.0, and an EXT4 file-system were used.