Open-Source NVIDIA GeForce RTX 2000 "Turing" 3D Driver Performance
Going back to the end of 2018 was initial open-source "Nouveau" driver work on RTX 2000 / Turing GPUs as of Linux 5.0. But due to the lack of signed firmware images at the time, there was no actual hardware acceleration but just display/modesetting. The accelerated Turing support has come together recent so now here are benchmarks showing the open-source GeForce RTX 2060 and RTX 2080 performance of this open-source driver compared to the proprietary official driver.
The accelerated RTX 2000 series support on the kernel side came at the start of the year for Linux 5.6 with the necessary changes in place. That came as NVIDIA finally published their signed, binary-only firmware for the GeForce GTX 1600 and RTX 2000 series GPUs.
Beyond Linux 5.6+ and the binary blobs in linux-firmware.git, only as of earlier this month did Mesa's NVC0 Gallium3D driver finally see Volta and Turing support merged for allowing 3D (and basic compute) to work on these newer NVIDIA GPUs. That Nouveau Gallium3D support is there for Mesa 20.2 due to be released at the end of August.
For your pleasure today are benchmarks of Linux 5.7 paired with Mesa 20.2-devel Git as of this weekend and linux-firmware.git for providing the basic open-source NVIDIA Turing support offered at this point by the open-source community. But there are several important caveats:
- The most pressing limitation remains that has been in place since the GTX 900 "Maxwell" series since NVIDIA began requiring signed firmware images... There isn't any re-clocking support yet. That means for GTX 900 through RTX 2000 series, the Nouveau kernel driver is bound to running at the boot clock frequencies that are generally very low due to not being able to properly handle power management with the graphics cards due to the signed firmware restrictions. We'll see if NVIDIA has a solution to announce soon or not, but right now this is the number one limitation for this open-source driver as you will see from the results.
- There isn't any open-source Vulkan driver (yet). So for right now you just have the OpenGL driver while many newer Linux games require Vulkan or the likes of DXVK with Vulkan for a better Steam Play gaming experience. There is some work going on that will help in the Vulkan direction like Nouveau's NIR support coming together, but for right now there is no Nouveau Vulkan driver for end-users.
- The Nouveau support is only exposing OpenGL 4.3 pending formal compliance with newer versions of the specification.
Meanwhile using NVIDIA's official but proprietary Linux driver will yield full support for the GPU. These benchmarks are putting the NVIDIA 440.82 proprietary driver against the Linux 5.7 + Mesa 20.2-devel open-source driver stack with various OpenGL games and other test cases. The GeForce RTX 2060 and RTX 2080 graphics cards were used for reference purposes.