PRIME Profiles Not Shown in nvidia-settings

[Olivier V]

Hi,

I've installed Nvidia 450 on new installation of Ubuntu 20.04.1.

Prime Render Offload works in manual mode with `__NV_PRIME_RENDER_OFFLOAD=1 __GLX_VENDOR_LIBRARY_NAME=nvidia`

But nvidia-settings says prime is not supported.
And so I have no prime entry in the nvidia window.

So I think the swith between integrated and nvidia GPU will not be automatic and the "on demand" does not work.

I asked nvidia developpers and they said it should be a ubuntu patch :
https://forums.developer.nvidia.com/t/prime-no-offloading-required-prime-is-it-supported/154181

**Computer :**
Asus A17-TUF766IU-H7074T

**OS Details :**
Ubuntu 20.04.1 with mainline 5.8.8 kernel
Nvidia Driver version : 450.66
Desktop Environment : Plasma
Window Manager : KDE

**Hardware Details**
Processor : AMD Ryzen 4800H
GPU : GeForce GTX 1660 Ti 6 Go

meloli@Asus-A17:~$ __NV_PRIME_RENDER_OFFLOAD=1 __GLX_VENDOR_LIBRARY_NAME=nvidia glxinfo | egrep "(OpenGL vendor|OpenGL renderer|OpenGL version)"
OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: GeForce GTX 1660 Ti/PCIe/SSE2
OpenGL version string: 4.6.0 NVIDIA 450.66

meloli@Asus-A17:~$ glxinfo | egrep "(OpenGL vendor|OpenGL renderer|OpenGL version)"
OpenGL vendor string: X.Org
OpenGL renderer string: AMD RENOIR (DRM 3.38.0, 5.8.8-050808-generic, LLVM 10.0.0)
OpenGL version string: 4.6 (Compatibility Profile) Mesa 20.0.8

meloli@Asus-A17:~$ nvidia-settings
(nvidia-settings:29678): GLib-GObject-CRITICAL **: 18:02:06.777: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
ERROR: nvidia-settings could not find the registry key file. This file should have been installed along with this driver at /usr/share/nvidia/nvidia-application-profiles-key-documentation. The
application profiles will continue to work, but values cannot be prepopulated or validated, and will not be listed in the help text. Please see the README for possible values and
descriptions.
** Message: 18:02:06.835: PRIME: No offloading required. Abort
** Message: 18:02:06.835: PRIME: is it supported? no

meloli@Asus-A17:~$ apt-cache policy nvidia-driver-450
nvidia-driver-450:
  Installé : 450.66-0ubuntu0.20.04.1
  Candidat : 450.66-0ubuntu0.20.04.1
 Table de version :
 *** 450.66-0ubuntu0.20.04.1 500
        500 http://ppa.launchpad.net/graphics-drivers/ppa/ubuntu focal/main amd64 Packages
        100 /var/lib/dpkg/status

[Daniel Letzeisen (dtl131)]

If "prime-select query" returns "on-demand" and the Nvidia GPU is used when you run with those variables, then on-demand is working correctly. Maybe I'm wrong, but it sounds like you are asking about seamless/automatic load-based switching, which is only available on Windows at this time.

Maybe this is more of a bug in nvidia-settings?

[Olivier V (forum-viennet)]

meloli@Asus-A17:~$ prime-select query
on-demand

meloli@Asus-A17:~$ nvidia-smi
| 0 GeForce GTX 166... Off | 00000000:01:00.0 Off | N/A |
| N/A 37C P8 1W / N/A

But the nvidia GPU is never used used automatic : I always have only 1W consumption.

I only have nvidia GPU working (and consumption about 10W) when using the prefix : __NV_PRIME_RENDER_OFFLOAD=1 __VK_LAYER_NV_optimus=NVIDIA_only __GLX_VENDOR_LIBRARY_NAME=nvidia

So nothing "on demand" but only manual switching.
It seems that eamless/automatic switching was available in 435 driver.

In nvidia-settings I don't have a PRIME Profiles as you can see on this doc : https://doc.ubuntu-fr.org/_media/nvidia-prime-profiles.jpg
Here you can see another example with 435 driver and "On Demand" mode : https://www.reddit.com/r/Ubuntu/comments/deh01n/nvidia_on_demand/
You can see the three mode. For me "On Demand" should be automatic... as in windows and in 435 version.

Nothing like this in the 450 driver.

[Daniel Letzeisen (dtl131)]

"For me 'On Demand' should be automatic."
That is not how Nvidia is using the term: https://download.nvidia.com/XFree86/Linux-x86_64/450.66/README/primerenderoffload.html
Again, automatic/seamless switching is not available on Linux.

"I only have nvidia GPU working (and consumption about 10W) when using the prefix"
That is expected. Just querying the GPU will not be enough to to ramp it up to full power. You can try nvidia-smi when you're running something demanding on the GPU and you'll likely see more power usage.

"In nvidia-settings I don't have a PRIME Profiles"
That is an issue. But keep in mind that is only a glorified GUI way of using 'sudo prime-select'
It wouldn't change anything since 'prime-select query' already shows you're already in on-demand mode.

[Olivier V (forum-viennet)]

OK thank you for your answer.
I understand know : only "manual" switch.

Good news for me : everything works as it have to do. Only a little GUI bug.

You are right to change the title.

[Daniel Letzeisen (dtl131)]

You're welcome. I subscribed the "Graphics Drivers" team that are responsible for the PPA. Maybe they can answer why you lack Prime Profiles and receive the message:
ERROR: nvidia-settings could not find the registry key file.

[Olivier V (forum-viennet)]

Thank you.

The message is :

meloli@fixe:~$ nvidia-settings
** Message: PRIME: No offloading required. Abort
** Message: PRIME: is it supported? no

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.