SUMMARY For example, when the MPV player is started in full-screen mode, the composer are suspended. After the player returns to window mode, the composer are resumed. After that, all Plasma effects get stuttering. If all opened app windows are maximized and again minimized, then Plasma effects work smoothly again. STEPS TO REPRODUCE 1. Run MPV video in window mode (Plasma effects work smoothly) 2. Switch MPV to full screen mode and back to window mode (after compositing resume all animations stuttering) 3. (Optional) Maximize and again minimize all opened application windows - Plasma effects work smoothly again ---OR--- 1. Open few random apps 2. Press Alt+Shift+F12 to suspend compositions 3. Press Alt+Shift+F12 to resume compositions - now all Plasma effect stuttering (especially visible at the desktop cube) 4.(Optional) Maximize and again minimize all open application windows - Plasma effects work smoothly again. OBSERVED RESULT Animations of Plasma effects stuttering after pausing and resuming the composition. EXPECTED RESULT All animations work smoothly as before pausing and resuming the composition. SOFTWARE/OS VERSIONS Operating System: Arch Linux KDE Plasma Version: 5.19.0 KDE Frameworks Version: 5.70.0 Qt Version: 5.15.0 Kernel Version: 5.7.2-arch1-1 OS Type: 64-bity Processors: 8 × Intel® Core™ i7-4790K CPU @ 4.00GHz Memory: 15,6 GiB RAM-u Graphics Processor: GeForce GTX 980/PCIe/SSE2 Graphics drivers: nvidia 440.82-21 (proprietary drivers) ADDITIONAL INFORMATION The bug faced since the last update of KDE Plasma to version 5.19.0 and previously, the bug didn't occur with the same graphics drivers and the older KDE Plasma 5.18.5. (and older kwin) For Intel iGPU's, this problem doesn't occur.
This bug is also revealed when switching the scaling methods or display engine in the composer's settings window.
Note/Tip: This bug occurs when there is even one minimized application on the taskbar. If no application window was minimized while pausing and resuming the composer, the error does not appear.
I have run into this issue since updating to latest KDE Plasma 5.19.3 from 5.18.x. Running Arch Linux and also with same GTX 980 with proprietary nvidia driver (Tried 440.x and newer 450.x drivers and is no different. Hopefully this can be looked into on kwin side as this is quite annoying and has forced me to disable compositing entirely which is not so nice in the aesthetic of the plasma desktop.
This occurs for me too. In Plasma 5.20.3 latest Arch Linux. Also I have reported this bug too in here : https://bugs.kde.org/show_bug.cgi?id=428729 . But sadly no one noticed it. It's such a major bug that causes huge dent in user experience :(
I confirm there is a bug. After exiting the game (Port or DXVK) Plasma starts to "stutter". The effects are preserved but smoothness is lost. To reproduce the bug, I need to play for a while, there is no time binding, you can start and close the game and it will appear. Msi Gtx 770 Driver 455 Kde 5.20.4
I cannot reproduce it with AMD. Do you all have NVIDIA GPUs?
*** Bug 428729 has been marked as a duplicate of this bug. ***
(In reply to Vlad Zahorodnii from comment #6) > I cannot reproduce it with AMD. Do you all have NVIDIA GPUs? Yup I have a Nvidia GTX 1060 6GB. Actually this issue stopped occurring for me. I had this issue happen to me in 5.19 and 5.20-5.20.4 if I disabled VSync in compositor settings and enabled Force Composition Pipeline in Nvidia Settings (I have setup is to be Persistent in /etc/X11/xorg.conf.d/20-nvidia.conf and also added "TripleBuffer" "On" line there as mentioned in ArchWiki. Also I have KWIN_TRIPLE_BUFFER=1 in /etc/profile.d/kwin.sh). But in 5.20.4 I turned VSync to Automatic and this issue was solved and I didnt have any stuttering too after resuming compositor using 455 drivers. But once 460.32 driver dropped, I noticed stuttering when moving windows even without disabling and enabling compositor. So now I set VSync to off in Compositor settings and the issue doesnt happen anymore. So strange....
(In reply to Vlad Zahorodnii from comment #6) > I cannot reproduce it with AMD. Do you all have NVIDIA GPUs? Yes Nvidia here. I still face this with latest plasma and any Nvidia driver from 440.100 to latest 460.xx version. It seems that it was introduced in plasma 5.19. I also have triple buffering set in env and force composition pipeline used across multiple monitors, whether it is relevant or not. I don't know where the problem lie but it is certainly annoying. It's like the stutter effect is worsened the more windows are minimized at the moment the compositor resumes. When only 1 the stutter is less bad and if say 5 windows are in a minimized state when compositor resumes the stutter is very bad, like a slideshow. As was originally mentioned by op the normal smooth effects only come back when each and every window that was minimized on compositor resumption is maximized again. You can see the effects get more and more smooth again in an apparent increment with each window that is maximized again. Hopefully you can understand that, and maybe it can be looked into. Thanks.
Still present in kwin 5.22.4, with Nvidia 470.63.01. Completely fixed in KwinFT, so frankly that's what I'll be using from here on out.
Still present in: Operating System: Arch Linux KDE Plasma Version: 5.22.4 KDE Frameworks Version: 5.84.0 Qt Version: 5.15.2 Kernel Version: 5.13.9-arch1-1 (64-bit) Graphics Platform: X11 Graphics Processor: NVIDIA GeForce GTX 980/PCIe/SSE2
*** This bug has been marked as a duplicate of bug 425856 ***