conflicting with nvidia-xruns bbswitch config

[deisi]

I encountered some issues due to a prior config with nvidia-xrun. optimus-manager was not able to use bbswitch to switch between the GPUs. I thus like to share my findings. Maybe we can improve documentation a little.

After following the instructions, I was not able to follow https://github.com/Askannz/optimus-manager/wiki/A-guide--to-power-management-options#configuration-3--bbswitch even though I knew it works due to prior bbswitch usage. To get everything working, I needed to also revert nivida-xrun config. I did:

# Revert loading of bbswitch module
rm /etc/modules-load.d/bbswitch.conf

# Revert disabeleing of nvidia gpu
rm /etc/modprobe.d/bbswitch.conf 

# Revert xinit config
rm ~/.nvidia-xinitrc

I basically followed https://wiki.archlinux.org/index.php/Nvidia-xrun#Configuration backwards.

I'm not sure how to best mention this in the readme or wiki. Maybe a warning saying that optimus-manager cant use bbswitch correctly if nvidia-xrun config is not reverted or something along these lines. I think in most cases people are able to do what I did and just read nvidia-xrun config section backwords. However a tip that this might be necessary is useful IMO.

[calebreister]

I encountered the same issue on my ThinkPad T470p, and can confirm that removing the specified files does indeed fix the issue. It is worth noting that the issue is not with bbswitch, since I was able to turn the GPU on and off without any trouble.

[Askannz]

Interesting, thanks raising the issue. Seems like it's indeed worth adding a warning about nvidia-xrun in the doc.

[Askannz]

Added a warning in the README.