Open-Source NVIDIA Vulkan Driver "NVK" Lands Improvements For ReBAR

[phoronix]

Phoronix: Open-Source NVIDIA Vulkan Driver "NVK" Lands Improvements For ReBAR

The open-source NVIDIA "NVK" Vulkan driver within Mesa 24.1-devel has seen improvements made for systems capable of Resizable BAR "ReBAR" support...

https://www.phoronix.com/news/Mesa-NVK-Vulkan-NVIDIA-ReBAR

[toughy]

This is so good to hear. ReBAR is such a simple and useful feature, everyone should benefit from it, and should be the default.

I hope this works for Turing (GTX 1600 / RTX 2000) GPUs as well, which need an UEFI mod to enable ReBAR.

Sadly when I enable GSP-RM on the kernel command line, for my 2080 Ti on Fedora with the daily kernel, I only get software rendering (it is worse then without GSP-RM) I have the firmware files in place and there is no error in dmesg. Does anyone know what I can do ?

My 3090, on the other hand (in a different computer), appears to just work...

[sarmad]

ReBAR is an over-hyped tech. According to benchmarks, in most cases you see no difference in performance, and in best cases you see a 5% improvement in framerate (which is about 2 or 3 frames only on a 60fps game). I guess the good thing about it is that there are no drawbacks in keeping it on. So, yeah, good to have it enabled, but don't expect any visually noticeable changes.

[-MacNuke-]

Last time I checked: At least on Windows with Nvidia GPUs ReBAR sometimes does lower the performance of some games (i.e. The Last of Us Part 1). That's why, at default the driver only enables it for supported games and is off by default.

[mdedetrich]

ReBAR is an over-hyped tech. According to benchmarks, in most cases you see no difference in performance, and in best cases you see a 5% improvement in framerate (which is about 2 or 3 frames only on a 60fps game). I guess the good thing about it is that there are no drawbacks in keeping it on. So, yeah, good to have it enabled, but don't expect any visually noticeable changes.

Its not overhyped, in some games it can improve performance by double digit percent which is nothing to scoff at. Its just whether it makes a difference or not is highly dependant on the game engine (and in some cases it even causes slight regressions which is why AMD/NVidia toggles it off for these specific games).

[RealNC]

This is so good to hear. ReBAR is such a simple and useful feature, everyone should benefit from it, and should be the default.

Apparently very few games benefit from it, but in many it actually hurts perf. On Windows, the Nvidia driver uses a whitelist. It's off in majority of the games except for a few that were whitelisted.