[ANNOUNCEMENT] Adaptive Sync / Freesync / VRR not working

what are those issues?

Missing kernel module for power management. affects both cpu and gpu

ah k, they’re enabled here on Arch Linux, both loaded too

why i am unable to see it on fedora 40 kernel 6.8.7?

gsettings set org.gnome.mutter experimental-features "['variable-refresh-rate']"

the problem is that i am unable to use it with fractional scaling when i enter it is there a comand to use both?

Are you sure this actually landed in 6.9? I’m on a freshly booted 6.9 compiled from sources, variable-refresh-rate is enabled in dconf and I’m on Gnome 46.1. Yet nothing about prefered refresh rate showing in settings.

drm_info | grep vrr shows 9 entries, yet only the one under connector 0 is set to 1, while the other 8 are still 0.

drm_info | grep vrr
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 1
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
Linux  6.8.8-300.fc40.x86_64 #1 SMP PREEMPT_DYNAMIC Sat Apr 27 17:53:31 UTC 2024 x86_64 GNU/Linux
gnome-shell --version
GNOME Shell 46.1

image

Debian testing, KDE Plasma 5, appears that it detects the internal screen as VRR capable just fine, I see Adaptive sync setting in the Display Configuration setting.

Interesting. Maybe something didn’t fully reload. Just waking up from hibernation today and now it shows up.

Is there some kind of universal fps counter overlay for Linux to check how well this works?

I’m running Kubuntu 24.04 on Wayland with mainline kernel 6.9.2 via the mainline tool from PPA for cappelikan : cappelikan . I’m still not seeing adaptive sync options in Display and Monitor in KDE system settings.

I’ll keep poking and see if I can figure out why it’s not working on 6.9, but if anyone has any additional ideas, I’d appreciate any input.

On openSUSE Tumbleweed, variable refresh rate doesn’t show up, although that may be due to being on X11.

There are pretty good directions here on how to enable it. These are written for Arch, but I expect relatively portable.

https://wiki.archlinux.org/title/Variable_refresh_rate

If VRR is enabled. Is there a command to show the current refresh rate that can vary?

No, but you can use this to see if it’s working or not.

Spoiler, VRR is not working.

Should work automatically with the Plasma Wayland session, tho for me, my external monitor routed through a TB dock is the one missing VRR :sweat_smile:

Yup! Unfortunately there’s a Plasma bug bugging me too much on Wayland for that to be viable, but a new snapshot updating Plasma to a version that doesn’t have that bug is imminent. Once that’s in, I plan to switch to Wayland full-time.

1 Like

I’m on Debian testing, 6.7.12 kernel, KDE Plasma 5.27.10, Wayland, and I don’t see the VRR options.

One of the replies above says that the patch should be in 6.7.12. drm_info shows 0 for vrr_capable:

➜  ~ drm_info | grep vrr 
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚   β”‚       β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0
β”‚           β”œβ”€β”€β”€"vrr_capable" (immutable): range [0, 1] = 0

Any ideas?

Upgrade to a kernel with the fix that recognizes the panel supports vrr.

I thought 6.7.12 would be fine based on this comment:

When I get more free time, I’ll manually download Debian’s kernel source and see if it contains the patch (and patch it myself if needed).