[SOLVED] Fractional Scaling unusable in Cinnamon

rellieberman · 2024-06-25 12:01:46

Hi,
I've got a new 4k display and when trying to use fractional scaling (on arch running Cinnamon DE) my screen goes all jumpy and blinks like crazy.
Now I understand this is an experimental feature in Cinnamon, but I would still be happy for any help trouble shooting this. What setting should I look at? What info should I look up to diagnose the problem? Is there anywhere I can follow the current development of fractional scaling in Cinnamon.
Any advice or pointing in the right direction would be greatly appreciated,
rellieberman

Last edited by rellieberman (2024-06-26 09:08:47)

rellieberman · 2024-06-25 19:42:44

I played around a bit more, and discovered that when running only on Nvidia gpu the screen remains usable when using fractional scaling, but instead of scaling the screen gets extended beyond the monitor borders

seth · 2024-06-25 21:35:22

Since https://wiki.archlinux.org/title/Cinnamon doesn't have a wayland session and you've a hybrid system and the underlying gnome is picky for using wayland on nvidia:
Is this cinnabun on X11 w/ xrandr --scale??

loginctl session-status
xrandr -q
pacman -Qs xf86-video

and in doubt please post your Xorg log, https://wiki.archlinux.org/title/Xorg#General

rellieberman · 2024-06-25 22:22:38

I'm using X11 with xrandr (and build in cinnamon scale) getting the same resault

the results of xrandr -q when integer scaling is used:

 xrandr -q
   DP2 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 600mm x 340mm
   3840x2160     60.00*+  30.00    25.00    24.00    29.97    23.98  
   1920x2160     59.99  
   2560x1440     59.95  
   2048x1280     59.99  
   1920x1080     60.00    50.00    59.94    25.00    24.00    23.98  
   1600x1200     60.00  
   1600x900      60.00  
   1280x1024     75.02    60.02  
   1152x864      75.00  
   1280x720      60.00    50.00    59.94  
   1024x768      75.03    60.00  
   800x600       75.00    60.32  
   720x576       50.00  
   720x480       60.00    59.94  
   640x480       75.00    60.00    59.94  
   720x400       70.08

I have both drivers installed:

 pacman -Qs xf86-video
  local/xf86-video-intel 1:2.99.917+923+gb74b67f0-2 (xorg-drivers)
    X.org Intel i810/i830/i915/945G/G965+ video drivers
 local/xf86-video-nouveau 1.0.17-3 (xorg-drivers)
    Open Source 3D acceleration driver for nVidia cards

And this is the xorg log when changing the scaling to 1.75 and back with intel GPU

[  7460.594] (II) intel(0): resizing framebuffer to 4384x2466
[  7460.676] (II) intel(0): switch to mode 3840x2160@60.0 on DP2 using pipe 0, position (0, 0), rotation normal, reflection none
[  7462.492] (II) intel(0): resizing framebuffer to 3840x2160
[  7462.533] (II) intel(0): switch to mode 3840x2160@60.0 on DP2 using pipe 0, position (0, 0), rotation normal, reflection none

seth · 2024-06-26 06:07:33

The randr output suggest no scaling at all, but in any event remove xf86-video-intel, ir at least make sure to https://wiki.archlinux.org/title/Intel_ … ecent_GPUs
But really remove that.
In doubt please post your Xorg log, https://wiki.archlinux.org/title/Xorg#General

rellieberman · 2024-06-26 09:06:22

Removing xf86-video-intel and letting did the trick.
Fractional scaling works well now, Thank you very much!

I have a followup though. I now notice that in fractional setting video playback is jittery, with screen tearing (on youtube/netflix). When using Integer scaling this does not happen (100% or 200% scaling).
Shouldn't the scaling only affect the GUI but no video playback? This is all without xf86-video-intel installed, any clues here?
Thanks again for you help

Last edited by rellieberman (2024-06-26 09:29:59)

seth · 2024-06-26 14:04:10

This depends on what that scaling actually does ("xrandr -q" w/ fractional scaling?)
Generally the scaling causes an indirection that'll get in the way or is just too much load for the IGP - you can test the performance w/ the intel ddx driver, but will have to set DRI to iris (otherwise you'll end up w/ software rendering)

Arch Linux

#1 2024-06-25 12:01:46

[SOLVED] Fractional Scaling unusable in Cinnamon

#2 2024-06-25 19:42:44

Re: [SOLVED] Fractional Scaling unusable in Cinnamon

#3 2024-06-25 21:35:22

Re: [SOLVED] Fractional Scaling unusable in Cinnamon

#4 2024-06-25 22:22:38

Re: [SOLVED] Fractional Scaling unusable in Cinnamon

#5 2024-06-26 06:07:33

Re: [SOLVED] Fractional Scaling unusable in Cinnamon

#6 2024-06-26 09:06:22

Re: [SOLVED] Fractional Scaling unusable in Cinnamon

#7 2024-06-26 14:04:10

Re: [SOLVED] Fractional Scaling unusable in Cinnamon

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