Apple's Enhanced OpenGL Stack Versus Linux

Right from the start, these OpenGL tests proved to be interesting. While we have found issues when running the popular open-source Nexuiz game going back to the original Mac OS X 10.6 release and had even communicated with Apple regarding problems in this area, their OpenGL performance in this test continues to be rather interesting. With Nexuiz on Snow Leopard, when running this game full-screen at lower resolutions than the native resolution, the frame-rate struggles and is lower than when running at the native mode -- as if software acceleration is being used rather than properly accelerating it on the GPU. Even with Mac OS X 10.6.4 with the Snow Leopard Graphics Update, at 800 x 600 the frame-rate in Nexuiz was just 7.46, but at 1920 x 1080 the frame-rate jumped to 19.78. Under Ubuntu Linux with the proprietary NVIDIA driver, the results are as expected with the frame-rate dropping as the resolution/workload increases. At all resolutions tested up to 1920 x 1080, Ubuntu 10.04.1 LTS was faster, but at 1920 x 1080 when Mac OS X was properly handling Nexuiz, its performance trumped that of Ubuntu. Mac OS X 10.6.4 + SGLU were at 19 FPS while Ubuntu was at just 9 FPS. However, the Snow Leopard Graphics Update provided no measurable performance improvements in this game.

Running Urban Terror does not exhibit the problems Nexuiz does when running at lower resolutions, but the performance does struggle compared to Ubuntu Linux and the proprietary NVIDIA driver. At 800 x 600 the frame-rate with Ubuntu is 63% higher, at 1024 x 768 the frame-rate is 40% higher, but when running at 1600 x 1200 and 1920 x 1080 the frame-rate between the two operating systems are similar. With Urban Terror there again was no OpenGL performance gains provided by the Snow Leopard Graphics Update but the performance throughout all of the Mac OS X 10.6 point releases has been close to the same, although compared to Ubuntu there is still room for some performance optimizations.

Running the ioquake3-powered OpenArena game produced more numbers that are interesting although the SGLU did not provide any gains (or losses) for Apple. At 800 x 600, the NVIDIA driver on Linux was 31% faster while at 1024 x 768 the performance between Mac OS X and Ubuntu Linux was close to the same. At resolutions greater than 1024 x 768, however, the Linux performance fell behind that of Mac OS X. At 1920 x 1080, Mac OS X 10.6.4 with the Snow Leopard Graphics Update 1.0 was 33% faster than Ubuntu 10.04.1 LTS with the NVIDIA 256.44 display driver.