[PERF] All VR applications constantly stutter and miss the performance target

[DomiStyle]

Describe the bug
SteamVR constantly misses the performance target and stutters.

To Reproduce
Steps to reproduce the behavior:

1. Start SteamVR
2. Start any game or SteamVR Home

Expected behavior
Decent performance like in Windows.

System Information (please complete the following information):

• Distribution: Ubuntu 21.10
• SteamVR version: 1.20.4/1.14.x
• Steam client version: Oct 22 2021
• Opted into Steam client beta?: Yes
• Graphics driver version: Mesa 21.2.4 - kisak-mesa PPA (LLVM 12.0.1)
• Gist for SteamVR System Information: https://gist.githubusercontent.com/DomiStyle/2f95007de5c7ed54db8f11aea96cb06e/raw/9e0b022672a2afa1aa9760a1c6a0bc10d25a35c8/gistfile1.txt

Performance Data (optional, but very helpful):
I couldn't save the performance data because step 4 in the tutorial didn't work for me. There was no xterm window to complete setup.

However, I posted a video below.

Screenshots
Video of the issue in Synth Riders. This happens in all games, even SteamVR Home.

out.mp4

Additional context
I noticed that on Windows my GPU goes to 100% and the GPU pushes as many frames as it can (4ms), on Linux it seems to always hover slightly over the framerate target (8-10ms).

The 6900XT runs Synth Riders at 200% on Windows but struggles at just the normal 100% on Linux.

It doesn't matter what framerate or resolution I choose for the headset, they all stutter.

[wallcarpet40]

@DomiStyle I looked at the gist you posted and I compared my 6800XT to your GPU's speed and I'm getting about 1770 for the average speed. You are getting about 1000.

Are you sure that your GPU is boosting its clocks, when you're using SteamVR? I personally have to use a program called Corectrl to set the GPU in VR mode and set the maximum clock speed higher (it defaults to 500MHz, which is not good. The factory OC is 2415MHz I think).

[DomiStyle]

@wallcarpet40 I'm fairly certain that my GPU is not boosting, it seems to barely try to meet the framerate target.
Good call, will give corectrl a try. That could be it.

[ChristophHaag]

#469

[DomiStyle]

@wallcarpet40 Thanks, that helped immensely. Still not 100% but definitely playable now.

Base framerate is good now, stutters from time to time but depends on the game. Also an issue on Windows in some games.

in VR mode and set the maximum clock speed higher (it defaults to 500MHz

Did you mean the minimum clock speed? The defaults for me were:

Voltage offset: 0
Minimum MHz: 500
Maximum MHz: 2519

I left them as is for now but lifted the power limit and set the power profile to VR. I also set the CPU governer to performance if the vrserver starts.

@ChristophHaag Thanks, looks like the same issue.

[kisak-valve]

Closing as a duplicate of #469.