https://bugs.kde.org/show_bug.cgi?id=522991
--- Comment #12 from Joe Alec <[email protected]> --- Bug report 452219 is a gold mine really. I added `export KWIN_DRM_USE_MODIFIERS=0` to my `~/.config/plasma-workspace/env/kwin_vars.sh` and WOW, things now work as they did back in v6.6.4. This is causing agony every now and then accross the years, and eventually bug report 452219 ends up having something for everyone - https://www.reddit.com/r/kde/comments/11i8l25/nvidia_external_monitor_issues_lowfpsvsync_look/ - https://bbs.archlinux.org/viewtopic.php?id=286810 I no longer need to set env var `KWIN_DRM_DEVICES` and lose the ability to use my internal GPU for older games. An interesting observation comes from mangohud in the game Antichamber (OpenGL), before setting `KWIN_DRM_USE_MODIFIERS=0` (or if I set it to = 1) mangohud always shows both GPUs being used, Intel around ~40% and Nvidia around ~20%, and the usual FPS drop happens. But if I add `KWIN_DRM_USE_MODIFIERS=0` then Nvidia GPU usage is 0%, while Intel shows around ~50-60%, and no FPS drop at all!. I assume this causes kwin to stop copying render buffers, or disables some Nvidia-related bad code, but the docs https://invent.kde.org/plasma/kwin/-/wikis/Environment-Variables#kwin_drm_use_modifiers Already say: > This option can improve screen rotation and efficiency > but also breaks some display configurations at the moment Which assumingly means it should be disabled by default, @Zamundaaa can you please look into that. I'll attach pictures from this game showing what mangohud reports. -- You are receiving this mail because: You are watching all bug changes.
