NVIDIA Optimus On Ubuntu 13.10 Linux vs. Windows 8.1

Coincidentally with our first test, Nexuiz, Bumblebee didn't work out. Nexuiz would run under optirun in the Phoronix Test Suite, but would hang upon exiting. When testing Ubuntu 13.10 in its stock environment on the ASUS Zenbook Prime, the average frame-rate comes in at 28 FPS over Windows' 49 FPS. On Windows with Optimus being dynamically used, the discrete NVIDIA GPU was surely called into play while under Linux by default it's just running with the Intel Ivy Bridge GPU. When using DRI_PRIME=1 and running on the discrete NVIDIA GPU with the Nouveau driver, the performance is even slower and came out to just 6 FPS. The Nouveau driver still lacks re-clocking support and other critical features to offer competitive performance on modern NVIDIA GPUs. Unfortunately NVIDIA still has no fully proper Optimus support under Linux.

With OpenArena it's pretty much the same story where the Ubuntu 13.10 "out of the box" performance is low due to the OpenGL game just running off the Intel GPU and when switching to Nouveau the performance is in even worse shape. Fortunately for the rest of the tests, Bumblebee worked out. While Bumblebee led to faster performance due to the NVIDIA GPU now being used with the binary driver, the performance was still well short of the NVIDIA Windows 8.1 driver.

As the open-source Mesa/Gallium3D drivers don't yet properly handle Unigine Heaven 4.0 (nor Unigine Valley), for this testing the only Linux tests were done when using Bumblebee with the proprietary driver. With this test we still see that using Bumblebee does have some performance overhead for Linux over where the tech demo is running on Microsoft Windows. Normally the performance is identical between Windows and Linux with NVIDIA's driver.