https://bugs.kde.org/show_bug.cgi?id=511793
--- Comment #7 from [email protected] --- (In reply to captainskelly0 from comment #6) > (In reply to william.drumright from comment #4) > > On KDE Plasma Wayland (KWin 6.5.4) with AMD GPU, games that grab/release the > > mouse cursor (e.g. World of Warcraft WOTLK / Classic) show severe frametime > > stalls when right-clicking to control the camera. > > > > This does not occur on NVIDIA hardware. > > > > Environment (affected system) > > OS: Archy > > KDE Plasma: 6.5.4 > > Session: Wayland > > GPU: AMD RX 7900 XTX > > Driver: amdgpu + Mesa > > Monitor: 165 Hz > > Mouse: 1000 Hz polling > > Game runtime: Wine / Proton GE (DXVK) > > Game: World of Warcraft WOTLK (legacy client) > > > > Symptoms > > Right-clicking to rotate camera causes a visible hitch / microstutter > > MangoHud FPS briefly drops to 0 exactly when the mouse button is pressed or > > released > > > > What fixes the issue > > KWIN_DRM_NO_DIRECT_SCANOUT=1 > > → Completely resolves the stutter and FPS→0 drops > > > > Gamescope > > → Also resolves it, but causes alt-tab issues and occasional mouse/camera > > desync > > > > Partial workaround > > Disabling in-game hardware cursor (adds mouse latency) > > > > > > Control test (no issue) > > Tested on a laptop with NVIDIA GPU using the same game and runtime: > > CPU: Intel i7 (12th gen) > > GPU: RTX 3070 Ti > > OS: Archy > > Session: KDE Wayland > > Mouse: 1000 Hz polling > > Same Wine/Proton GE runner > > → No stutter, no FPS drops, no Gamescope or env vars needed > > > > > > Likely cause > > Appears related to KWin Direct Scanout being invalidated by cursor > > visibility / pointer grab changes, causing a brief present stall. Disabling > > Direct Scanout globally avoids the issue. > > Where are you adding `KWIN_DRM_NO_DIRECT_SCANOUT=1` to? I may have spoken too soon. While enabling the KWIN_DRM did smooth out the FPS stutter, moving to a busy part of the game causes the mouse to have really bad latency. Going back to GameScope may be the best option until this bug gets addressed upstream. If you want to test it yourself: Create an environment directory and file: mkdir -p ~/.config/environment.d nano ~/.config/environment.d/kwin.conf Add this line to the file: KWIN_DRM_NO_DIRECT_SCANOUT=1 Log out and back in -- You are receiving this mail because: You are watching all bug changes.
