Tools for easy graphics switching on multi-gpu Linux systems

[Marlock]

This is especially relevant for gaming laptops, many of which have on-chip Intel graphics and a stronger but more power-hungry Nvidia (and in more rare cases AMD) dedicated GPU chip. Running demanding tasks on the stronger gpu is important, but also

It also can apply in desktop setups, but with no power constraints usually the user will just use the most powerful gpu constantly and disable the other.


On windows it's been a while (already a decade?) since laptop gpu drivers started automatically offloading intensive tasks to the dedicated gpu while running all others in the integrated one. In my experience years ago, it was not very transparent or tweakable, but was a generally sane default, leading to a nice balance of battery life and performance.


On Linux, at least when I first migrated, it was necessary to reboot to switch between gpus, and they were used for all tasks in that session, regardless of graphical complexity.

Later I've found out there were ways (Optimus and Prime) to explicitly instruct the Nvidia GPU to be used for a specific task, but this has proven (at the time) to be hit or miss to install, and some people also find it a chore to use (editing shortcuts for each specific app that needs the extra power).


Enters a new push to make graphics switching more flexible and easier to the end-user on Linux, including NVIDIA On-Demand (a new way to offload specific intensive tasks to the discrete NVIDIA GPU) and MATE Optimus (a simple GUI for Nvidia graphics switching).


The news that got me interested is this:
https://www.omgubuntu.co.uk/2019/09/nvidia-optimus-linux-switching-applet
and later this:
https://www.gamingonlinux.com/articles/the-handy-nvidia-optimus-gpu-switcher-just-added-support-for-more-linux-desktops.14985

According to that, the newest versions (already in repos for Ubuntu 19.10 but not 18.04 or 19.04) include support for NVIDIA On-Demand Switching (if I understood correctly it switches all tasks from one to the other gpu without needing a reboot?), "offload-glx" and "offload-vulkan" launchers (these 2 are for NVidia PRIME offloading of specific apps)

And despite the MATE name, the app works not only on that DE but also on Cinnamon, GNOME, Budgie, KDE and LXQt.


Are there any other improvements and tools that a multi-gpu user should know about? I'm itching to know!

[Roboron]

Note only the new drivers are supported, and that means that older cards still don't support proper offloading. I have one using 390 drivers, and currently the best solution is still nvidia-xrun, wich opens a new X session in the nvidia card, or the optimus switcher applet, which lets you exit your current session to change the GPU you are using.

[Marlock]

adjusted the OP due to more cool news about MATE Optimus
https://www.gamingonlinux.com/articles/the-handy-nvidia-optimus-gpu-switcher-just-added-support-for-more-linux-desktops.14985