Bug 498677

Summary: VRR always enabled in Wayland
Product: [Plasma] kwin Reporter: dougg0k
Component: wayland-genericAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED UPSTREAM    
Severity: normal CC: nate, xaver.hugl
Priority: NOR    
Version First Reported In: 6.2.5   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description dougg0k 2025-01-15 02:23:18 UTC
SUMMARY
I've been trying to find out the reason why GPU usage are low in Wayland compared to X11, not matter what settings and environment variables you set. Among other issues related to VRR/Gsync.

https://discuss.kde.org/t/low-gpu-usage-in-wayland/28297

I recently found a few things that could related to all this in some way and could be a bug. 

Confirmation was done through the command reported by another person, and I got the same results here with all settings from the UI and through environments disabling vsync/vrr/triple buffer and everything else that is possible.

https://www.reddit.com/r/linux_gaming/comments/18lxzwm/comment/ke3mpwy/

STEPS TO REPRODUCE
1. Install: https://aur.archlinux.org/packages/drm_info
2. Type: drm_info | grep VRR_ENABLED

OBSERVED RESULT
│   │       ├───"VRR_ENABLED": range [0, 1] = 0
│   │       ├───"VRR_ENABLED": range [0, 1] = 0
│   │       ├───"VRR_ENABLED": range [0, 1] = 0
│           ├───"VRR_ENABLED": range [0, 1] = 0

EXPECTED RESULT
To not be enabled, all everything else are disabled.

SOFTWARE/OS VERSIONS
Operating System: CachyOS Linux (Arch)
KDE Plasma Version: 6.2.5
KDE Frameworks Version: 6.10.0
Qt Version: 6.8.1
Kernel Version: 6.12.9-3-cachyos (64-bit)

ADDITIONAL INFORMATION

Inside the the first url, it should contain other relevant urls for similar topics. Like the similar low GPU usage when having AsyncFlipSecondaries enabled in X11, where if all are disabled in X11, the usage are close to full or full.
Comment 1 dougg0k 2025-01-15 03:48:07 UTC
If this is in fact why, then this could also be the reason for this not work.

https://forums.developer.nvidia.com/t/cant-enable-ulmb-2-on-wayland/277478
Comment 2 Zamundaaa 2025-01-15 12:10:30 UTC
drm_info says it is disabled by KWin. Please report this to NVidia.