Arch Linux

kokoko3k

Member

Registered: 2008-11-14

Posts: 2,457

kwin performance under wayland.

Hi,
I just tried to start plasma under wayland, but I've been very disappointed by kwin performance.
While under x11 my desktop is butter smooth, under wayland, the animations are definitely not.
It seems that when doing basic animations like window maximize/restore or even moving, the compositor drop frames; not consistently.

My gpu is not the fastest one, an igpu from an i5-4590 (Haswell), and it is driving 2 displays at 1920x1080, but I repeat, under X everything is butter smooth.

What is your experience?

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V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,104

Re: kwin performance under wayland.

Works just fine here on a RX 6900 XT which granted is an order of magnitude more capable. FWIW check your actual renderer in use with e.g. glxinfo -B or so, make sure you are not hit by relying on the software renderer due to the mesa/mesa-amber split, see e.g.: https://bbs.archlinux.org/viewtopic.php?id=275232

kokoko3k

Member

Registered: 2008-11-14

Posts: 2,457

Re: kwin performance under wayland.

No problems with Opengl acceleration ,but trading off latency versus smoothness partially solved this.
(note that under Xorg, i can keep the latency to the lowest setting, but i've to say that i don't think it is really doing something).

By the way, i noticed that if i keep the fps benchmark effect active, the stutters go away so maybe the intel card were going into a low power producing the stuttering, so I checked with intel_gpu_top under Wayland and Xorg, but the usage didn't differ at all.

-EDIT-
Still, the following:

# echo 1000 > /sys/class/drm/card1/gt_min_freq_mhz 

Definitely helps.

Last edited by kokoko3k (2022-03-31 15:23:59)

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Help me to improve ssh-rdp !
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kokoko3k

Member

Registered: 2008-11-14

Posts: 2,457

Re: kwin performance under wayland.

Turns out that things can improve by using:  "force smoothest animations" in compositor settings.
However, it seems that hardware mouse behaves differently in Wayland, and it is rendered synchronously to the rest of the desktop, that setting makes the mouse laggy and pointing to little elements becomes difficult.

However it is possible to revert to an older/legacy way for kwin to render things, by setting KWIN_DRM_NO_AMS=1

Poor performance in kwin:
https://bugs.kde.org/show_bug.cgi?id=452119

Mouse stuttering/lagging in kwin:
https://bugs.kde.org/show_bug.cgi?id=452117

Mouse stuttering in Weston:
https://gitlab.freedesktop.org/wayland/ … te_1322457

Other than that:
* Since i havent found a way to inject new resolutions in the drm subsystem, I spent some time in crafting a custom EDID to enable higher refresh rates for my monitor which is running now at 75Hz instead of 60Hz to improve the lagginess.
* Raised minimum gpu speed from 200 to 300 (it still idles at 1Mhz, which is good):
echo 300 > /sys/class/drm/card0/gt_min_freq_mhz"

---

Help me to improve ssh-rdp !
Retroarch User? Try my koko-aio shader !