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themax

Member

Registered: 2013-05-14

Posts: 32

NVIDIA Optimus: how do I unload nouveau PRIME?

I have a Laptop with NVIDIA Optimus and I tried out render offloading using nouveau PRIME.
Works quite well actually.

How to reproduce it:
xf86-video-{intel,nouveau} are both installed
no specific xorg.conf is present

#turn on GPU
sudo tee /proc/acpi/bbswitch <<< ON
#load nouveau module
sudo modprobe nouveau
#start X, or start the display manager
startx
#sudo systemctl start gdm.service

then, in a terminal

xrandr --listproviders

output:

Providers: number : 2
Provider 0: id: 0x8a cap: 0xb, Source Output, Sink Output, Sink Offload crtcs: 2 outputs: 2 associated providers: 0 name:Intel
Provider 1: id: 0x66 cap: 0x7, Source Output, Sink Output, Source Offload crtcs: 2 outputs: 5 associated providers: 0 name:nouveau

Now let's use nouveau as offload source

xrandr --setprovideroffloadsink nouveau Intel

and now I can run apps on the NVIDIA card like this:

DRI_PRIME=1 glxgears

Now my question:
The graphics card stays powered on because the nouveau module is loaded, and the nouveau module is in use by xrandr.
Can I somehow still unload nouveau and turn off the GPU or do I have to restart the Xorg server?

Arup

Member

From: Earth

Registered: 2014-02-20

Posts: 95

Re: NVIDIA Optimus: how do I unload nouveau PRIME?

The nouveau is shut down once the program using it is terminated, check the sensors, you will see temps indicated during noueveau use.