openSUSE Touts Improved Multi-GPU Switching Support

[phoronix]

Phoronix: openSUSE Touts Improved Multi-GPU Switching Support

Te openSUSE project shared today that there is enhanced multi-GPU switching support to enjoy now with openSUSE Linux...

https://www.phoronix.com/news/openSUSE-switcherooctl

[Vortex Acherontic]

Ah man I'd wish I knew this sooner. Then I wouldn't have waste time in developing OptimusUI as a user interface for prime-select (aka suse-prime, nvidia-prime-select, fedora-prime-select and others) ... *sad noises*

[turtleidiot]

phoronix Typo: "Te openSUSE project shared today" should be "The openSUSE project shared today"

[Quackdoc]

really wish we had better tooling for these kinds of things, that being said, I have zero how I would do this, perhaps a vulkan layer hook that does what windows does for preferences so you can set applications to run on a specific gpu. You can already use vulkan layers to force a gpu to be a higher priority, so maybe this would be a more elegant solution.

edit: ofc mux switch stuff gets even more complicated.

[pWe00Iri3e7Z9lHOX2Qx]

Some aspects of using NVIDIA GPUs has certainly gotten better on OpenSUSE distros in the last year or so for people who wanted to do everything in a GUI. If an NVIDIA GPU is detected, YAST Software Repositories would suggest enabling the NVIDIA repo. Then in YAST software it would suggest installing all the correct NVIDIA packages for the driver + CUDA. I haven't tried any Tumbleweed installs on an Optimus setup in ~2 years though. The last time I did, the kernel boot params for blacklisting nouveau and the right modeset option weren't set up correctly. If you were new to Linux you'd have no idea how to fix it.

[carguello2]

mux switch stuff gets even more complicated.

A mux switch only makes the dual-gpu thing easier IMHO, for example:

Finish working, restart the Laptop...
Reboot to BIOS...
Choose the GPU to boot with...
Restart...

That's my workflow when I'm gaming on my Laptop and I've not run into issues.

[pWe00Iri3e7Z9lHOX2Qx]

A mux switch only makes the dual-gpu thing easier IMHO, for example:

Finish working, restart the Laptop...
Reboot to BIOS...
Choose the GPU to boot with...
Restart...

That's my workflow when I'm gaming on my Laptop and I've not run into issues.

But most people don't want to reboot at all to select which GPU to use. The system should be smart enough to use the dGPU by default for things you are likely to want to run on the beefier GPU (e.g. Vulkan games). And give them the ability to override / manually set as necessary.

[Quackdoc]

But most people don't want to reboot at all to select which GPU to use. The system should be smart enough to use the dGPU by default for things you are likely to want to run on the beefier GPU (e.g. Vulkan games). And give them the ability to override / manually set as necessary.

exactly this, swapping muxes should also be real time, if only bad enough for the screen to flicker as the compositor swaps.

[the-burrito-triangle]

Weird. The multiplexer should be able to switch inputs in real time... WTF are the laptop vendors / OS people doing wrong here? Maybe it's a BIOS problem, where the low level settings aren't accessible to the OS due to "security" reasons?

Anyways, on a desktop machine with multiple GPUs, I have no problem using the dGPUs headless (without a display attached) and outputting all video through the iGPU. The multiplexer approach is much more performant since the PCIe bus isn't being used to send data from one GPU to the other, but clearly it is still a shit show because no one understands how to configure the BIOS setting from the OS and maybe do a rescan of the PCIe bus if the dGPU was powered off and then on with the mux state change. This honestly shouldn't be that hard to do...

[the-burrito-triangle]

Now that I think about this, shouldn't the mux be accessible via i2c (or i3c)?