Bug 483015

Summary: Switching virtual desktops with apps touching panel bar causes lag
Product: [Plasma] kwin Reporter: dnl7
Component: generalAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED DUPLICATE    
Severity: normal CC: mobile.harvey, nate
Priority: NOR Keywords: qt6
Version: 6.0.1   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
See Also: https://bugs.kde.org/show_bug.cgi?id=482717
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: Showing the lag in switching desktops when the app is dragged in different positions

Description dnl7 2024-03-09 18:23:00 UTC
Created attachment 166814 [details]
Showing the lag in switching desktops when the app is dragged in different positions

Switching virtual desktops with apps touching panel bar causes performance issue

STEPS TO REPRODUCE
1. Make sure that multiple virtual desktops are enabled
2. Open any application in any virtual desktop
3. Either make the app fullscreen OR drag the app close enough to the panel bar so that the bar switches to non-floating mode
4. Switch to and from another virtual desktop using either hotkeys or the pager widget

OBSERVED RESULT
Kwin struggles to move smoothly between desktops, so the animation is laggy and slower.

EXPECTED RESULT
The switching animation should be fluid and take a consistent amount of time.

SOFTWARE/OS VERSIONS
Linux kernel: 6.7.9-arch1-1 (64-bit) 
KDE Plasma Version: 6.0.1
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.2

ADDITIONAL INFORMATION
I am using the proprietary Nvidia drivers because of compatibility with a video editing program. Unfortunately I don't remember if the issue occurred with Nouveau before I installed the proprietary drivers.
Comment 1 Nick 2024-03-16 12:13:19 UTC
Hi - I'm not able to duplicate this on Neon (Plasma 6.0.2) and Intel graphics. I suspect this is NVIDIA related. Could you please verify if this is still happening on 6.0.2? We may need someone with NVIDIA graphics to confirm this one.
Comment 2 Nate Graham 2024-03-18 21:54:34 UTC
Are you on X11? If so it seems like this may be Bug 482717.
Comment 3 Nate Graham 2024-03-19 19:12:15 UTC

*** This bug has been marked as a duplicate of bug 475468 ***
Comment 4 dnl7 2024-03-19 20:37:04 UTC
(In reply to Nate Graham from comment #2)
> Are you on X11? If so it seems like this may be Bug 482717.

I am on Wayland. The issue looks similar to 482717, but this one only occurs due to the windows proximity to a panel bar. Combining these two facts, I suspect that the problems are different, though it is still possible.