For the rest of our Qt4-driven QGears2 tests we switched from using X Render to its OpenGL back-end. Using the same gears test as earlier, with OpenGL the performance on the newer graphics stack had degraded to about 18% of its original speed.
The image scaling performance with OpenGL had also dropped tremendously using the newest packages.
We had used the Tremulous game benchmark for additional OpenGL testing that uses the ioquake3 engine and can normally run with Intel 965 graphics. Using Ubuntu 8.10 the game was nearly playable with frame-rates around 22 FPS at 1280 x 800, but with the Ubuntu 9.04 packages the average frame-rate had dropped to under 3 FPS.
Intel's current selection of integrated graphics processors (IGPs) are already slow when it comes to just the hardware, but with the graphics stack currently found in the Ubuntu 9.04 development branch the performance is simply miserable. The performance drops were nearly across the board with both 2D and 3D regressions being very noticeable.
Once X Server 1.6, xf86-video-intel 2.6, Mesa 7.4, and a stable Linux 2.6.28 kernel is out there we will be back with more tests. We'll also be testing the different packages in a vanilla configuration from source with different build options (such as GEM) in providing a much closer look at the Intel Linux graphics performance following all of the major work that has been taking place.