Mesa 9.2 X.Org/Mir Ubuntu 13.10 Performance Benchmarks
OpenArena 0.8.5 saw very significant performance improvements in moving from Mesa 9.1.6 to Mesa 9.2.0 with both a pure X.Org Server and when piped through XMir. Running OpenArena 0.8.5 at 1920 x 1080 saw a performance jump by about 30%.
The newer OpenArena 0.8.8 release that makes greater use of GLSL and other slightly more modern GL2 functionality saw only very minor performance improvements.
Urban Terror also saw no major changes in performance with Mesa 9.2.