KDE's Plasma Wayland Session Achieves Better Battery Life Than With X.Org

[phoronix]

Phoronix: KDE's Plasma Wayland Session Achieves Better Battery Life Than With X.Org

Last week I posted some benchmarks looking at the laptop battery life implications of GNOME's Wayland vs. X.Org sessions. From that testing with a Lenovo ThinkPad T14s Gen2 with AMD Ryzen 7 PRO 5850U laptop, the GNOME Wayland session led to around 3 Watt lower power consumption than with the same software stack while logging into the X.Org-based session. For those curious about the KDE Wayland vs. X.Org power impact, here is the same set of tests carried out in the KDE space...

https://www.phoronix.com/scan.php?page=news_item&px=KDE-Plasma-Wayland-Power

[tildearrow]

Proof that X.Org has too much overhead...

[extremesquared]

Promising. Wayland and pipewire seem to be approaching release-ready quality roughly evenly. Something something year of the Linux desktop.

[jntesteves]

3W may not seem much at first sight, but bear in mind this is the difference on a low-power laptop consuming only 24W. The percentages are 13.9% on GNOME and 11.1% on KDE, which are big differences. Say, if your laptop used to last 7h on a charge on GNOME Xorg, you can gain a whole extra hour just by switching to Wayland.

[aufkrawall]

With Xorg, you gotta differentiate between fullscreen with page flipping and compositor suspended/window unredirected and windowed mode with compositing active. So power efficiency actually is not bad with Xorg when watching a video in fullscreen, but is in windowed mode. Also, Mutter/Kwin Xorg compositing is very heavy on the GPU compared to Picom with Xrender backend. On top of that, Intel Xorg drivers are really bad. modesetting DDX ruins perfect presentation in mpv and xf86-video-intel ruins GL performance. Xorg situation with AMD GPU is far better in this regard.

But also Wayland results will get even better with more direct composition/scan-out optimizations done by applications. Next Plasma version should already be another nice improvement (at least with bleeding edge Mesa) and direct rendering into compositor for Firefox probably also will get flipped on by default in the forseeable future.

[sarfarazahmad]

I tried out plasma on wayland last week on Manjaro stable. Couple of things were still broken. HiDPI just didn't work, my touchpad settings from Xorg were not honored in wayland (I configured the settings in Kde system settings). I know it is Linux and you gotta do it yourself but I think the you-gotta-do-it-yourself aspect should be an opt-in. I mean I would call it production-ready when I just need to flip the switch in Sddm login screen and it works. I may be asking too much here.

[sarfarazahmad]

And it just hit me that my comment is completely tangential. On topic: this is great progress, props to the team and everyone involved for their efforts

[tuxd3v]

Proof that X.Org has too much overhead...

well I don't know..
Xorg seems to be consuming more power, but it seems that xorg is also more performant in games, also Xorg, maintains your laptop cooler for what we see in the graphs..

What for sure we take from the graphs. is that KDE xorg based, is more optimized than gnome xorg based...

[tuxd3v]

I just miss ssh the x11 forward thing, and we have no other option on datacenter..
if wayland manage to have the same feature, then will be a more broad option

[Ivan Dimitrov]

Proof that X.Org has too much overhead...

Well, actually in most of the cases Xorg has better performance. So in performance per watt cases I don't there will be that big of a difference. Xorg might have overhead but it also have years of optimizations lacking in Wayland.

I just miss ssh the x11 forward thing, and we have no other option on datacenter..
if wayland manage to have the same feature, then will be a more broad option

Pipewire is supposed to be this magic thing.