An Important GNOME Performance Fix Has Landed

[franglais125]

Interesting. I'll definitely be sticking with Xorg for a bit given all the problems on Wayland. Reading this bug report it looks like this only impacts X11 applications?

This only impacts Wayland!

[Holograph]

Wait, what? This assumption would only hold true with fixed-width fonts. You can't use (just) the length of a string to determine how to do layout with a variable width font. The whole idea behind this commit sounds broken and I'm not sure why that wouldn't be obvious. Am I missing something here?

[nh2_]

Wait, what? This assumption would only hold true with fixed-width fonts. You can't use (just) the length of a string to determine how to do layout with a variable width font. The whole idea behind this commit sounds broken and I'm not sure why that wouldn't be obvious. Am I missing something here?

Yes, even for non-monospace fonts, digits of digital clocks are usually in a fixed location. If they were right-aligned and in the seconds the digit 1 switched to 2, the entire clock would move a couple pixels do the left, which would make for a very annoying visual experience.

[leipero]

Were you running Wayland? I run my monitor at 120hz and GNOME on Wayland is absolute stutterfest, but it runs fine on x.org.

You can fix that by CLUTTER_DEFAULT_FPS=refreshrate (example for 120Hz, CLUTTER_DEFAULT_FPS=120), I've tested up to 105Hz and Gnome-Shell on X.Org can work up to 105FPS for sure (mind you, tested on lower resolutions on CRT display, but quite modest hardware anyway...).

There are things that affect Gnome-Shell performance since forever..., back in the day we could solve it wih "CLUTTER_PAINT=disable-clipped-redraws:disable-culling" and that was the only method that made GS usable and quite smooth to be honest, unfortunately, back in 3.18 (or maybe 3.20 not sure) that got broken and bug report for it stays opened..., so pretty much only method that made GS usable got broken and forgoten about.

Unfortunately also, even with those performance issues and generally terrible lags that got worse by every release, I can't see myself using any other DE, and no, don't even mention KDE to me, if it works for you, brilliant, good for you, I do not like it at all, so even if it worked better i still wouldn't use it, and that's about it.

[indepe]

Wait, what? This assumption would only hold true with fixed-width fonts. You can't use (just) the length of a string to determine how to do layout with a variable width font. The whole idea behind this commit sounds broken and I'm not sure why that wouldn't be obvious. Am I missing something here?

In my experience, digits 0-9 have the same width even for variable width fonts. (Maybe there are exceptions.)

[nh2_]

The "improved" 12.97ms number really sounds very disappointing.

I could run Gnome on Ubuntu 8.04 very smoothly on a 300 MHz Pentium 3, which is probably 100x slower than my current PC.

And with the current "new tech" stack on 100x faster hardware, rendering the idle desktop takes 13 ms of the 16 ms available for a frame? If true, this feels like we're moving backwards.

[indepe]

Not sure what exactly 12.97 ms refers to. Is that once a second? When I run Gnome on Ubuntu 17.10, X11, SystemMonitor shows all CPUs ~5% or lower, about 20% total. When I move the mouse over highlighting stuff, one of the curves will go up to about 40% for a moment.

Is their anything around 75% (12.97 / 16.66) with 18.04 and Wayland?

[Vash63]

This only impacts Wayland!

I said X11 applications. As in running an X11 application in Wayland.

I ask because the bug report is testing with glxgears, which runs through x11 - not testing with a native Wayland application, and the final comment of the bug report mentions that the bug can be anywhere in the "glx => xwayland => Mutter => KMS" path

[torturedutopian]

No, I'm on X11. (With NVidia drivers.)

Oh ! Well, I'm pretty sure this is Nvidia related. It does affect other DE. For instance, I have way way poorer performance under KDE when using the Nvidia drivers compared to using for instance a very old and very slow intel hd graphics. Frequent stuttering with the nvidia driver and absolutely constantly butter smooth with the intel HD whatever the cpu load. I'm pretty sure GNOME is affected too.