SUMMARY After changing any font in the system settings, the system starts stuttering to a point that moving a window or doing anything takes up to 4 seconds. STEPS TO REPRODUCE 1. Open system settings 2. Go to Font configuration page and change a font, e.g., for window title (even changing font size is enough) 3. Apply changes OBSERVED RESULT Screen blinks, font is changed, but system is slower and stutters. EXPECTED RESULT Font changed, but system keeps working as usual SOFTWARE/OS VERSIONS Linux/KDE Plasma: Fedora 35 (available in About System) KDE Plasma Version: 5.24.1 KDE Frameworks Version: 5.91 Qt Version: 5.15.2 ADDITIONAL INFORMATION Killing plasma-shell and restarting it does not solve the issue, only rebooting the machine works. The font settings were working fine in plasma 5.23.5.
I would like to point out that the problem arises on X, and not on wayland.
I don't know why the title of my bug has been changed, but no, the system is not unresponsive for a moment. It keeps being sluggish until I reboot my machine.
(In reply to Marco from comment #2) > I don't know why the title of my bug has been changed, but no, the system is > not unresponsive for a moment. It keeps being sluggish until I reboot my > machine. The issue is still present in Plasma 5.26.5, nad appears by changing essentially enything related to KWin. It makes customizing Plasma almost impossible, without a reboot.
Can you get the output of `qdbus org.kde.KWin /KWin supportInformation` when the system starts stuttering?
Sure, here is the log: Version ======= KWin version: 5.26.5 Qt Version: 5.15.8 Qt compile version: 5.15.7 XCB compile version: 1.13.1 Operation Mode: X11 only Build Options ============= KWIN_BUILD_DECORATIONS: yes KWIN_BUILD_TABBOX: yes KWIN_BUILD_ACTIVITIES: yes HAVE_X11_XCB: yes HAVE_EPOXY_GLX: yes HAVE_WAYLAND_EGL: yes X11 === Vendor: The X.Org Foundation Vendor Release: 12014000 Protocol Version/Revision: 11/0 SHAPE: yes; Version: 0x11 RANDR: yes; Version: 0x14 DAMAGE: yes; Version: 0x11 Composite: yes; Version: 0x4 RENDER: yes; Version: 0xb XFIXES: yes; Version: 0x50 SYNC: yes; Version: 0x31 GLX: yes; Version: 0x0 Decoration ========== Plugin: org.kde.kwin.aurorae Theme: __aurorae__svg__Monterey-dark-1.25x Plugin recommends border size: No onAllDesktopsAvailable: true alphaChannelSupported: true closeOnDoubleClickOnMenu: false decorationButtonsLeft: 0, 2, 9 decorationButtonsRight: 6, 3, 4, 5 borderSize: 0 gridUnit: 10 font: Cantarell,10,-1,5,50,0,0,0,0,0 smallSpacing: 2 largeSpacing: 10 Platform ========== Name: KWin::X11StandalonePlatform Cursor ====== themeName: Tela-dark themeSize: 24 Options ======= focusPolicy: 0 xwaylandCrashPolicy: xwaylandMaxCrashCount: 3 nextFocusPrefersMouse: false clickRaise: true autoRaise: false autoRaiseInterval: 0 delayFocusInterval: 0 shadeHover: false shadeHoverInterval: 250 separateScreenFocus: false activeMouseScreen: true placement: activationDesktopPolicy: 0 focusPolicyIsReasonable: true borderSnapZone: 10 windowSnapZone: 10 centerSnapZone: 0 snapOnlyWhenOverlapping: false rollOverDesktops: false focusStealingPreventionLevel: 1 operationTitlebarDblClick: 5000 operationMaxButtonLeftClick: 5000 operationMaxButtonMiddleClick: 5015 operationMaxButtonRightClick: 5014 commandActiveTitlebar1: 0 commandActiveTitlebar2: 28 commandActiveTitlebar3: 2 commandInactiveTitlebar1: 4 commandInactiveTitlebar2: 28 commandInactiveTitlebar3: 2 commandWindow1: 7 commandWindow2: 8 commandWindow3: 8 commandWindowWheel: 28 commandAll1: 10 commandAll2: 3 commandAll3: 14 keyCmdAllModKey: 16777250 condensedTitle: false electricBorderMaximize: true electricBorderTiling: true electricBorderCornerRatio: 0.25 borderlessMaximizedWindows: false killPingTimeout: 5000 hideUtilityWindowsForInactive: true compositingMode: 1 useCompositing: true hiddenPreviews: 1 glSmoothScale: 1 glStrictBinding: true glStrictBindingFollowsDriver: true glPreferBufferSwap: 101 glPlatformInterface: 1 windowsBlockCompositing: true latencyPolicy: renderTimeEstimator: Screen Edges ============ desktopSwitching: false desktopSwitchingMovingClients: false cursorPushBackDistance: 1x1 timeThreshold: 150 reActivateThreshold: 350 actionTopLeft: 0 actionTop: 0 actionTopRight: 0 actionRight: 0 actionBottomRight: 0 actionBottom: 0 actionBottomLeft: 0 actionLeft: 0 Screens ======= Active screen follows mouse: yes Number of Screens: 2 Screen 0: --------- Name: DP-2 Enabled: 1 Geometry: 1,0,1920x1080 Scale: 1 Refresh Rate: 60000 Adaptive Sync: incapable Screen 1: --------- Name: eDP-1 Enabled: 1 Geometry: 0,1080,1920x1200 Scale: 1 Refresh Rate: 59950 Adaptive Sync: incapable Compositing =========== Compositing is active Compositing Type: OpenGL OpenGL vendor string: Intel OpenGL renderer string: Mesa Intel(R) UHD Graphics (CML GT2) OpenGL version string: 4.6 (Compatibility Profile) Mesa 22.3.3 OpenGL platform interface: GLX OpenGL shading language version string: 4.60 Driver: Intel GPU class: Comet Lake OpenGL version: 4.6 GLSL version: 4.60 Mesa version: 22.3.3 X server version: 1.20.14 Linux kernel version: 6.1.7 Direct rendering: Requires strict binding: yes GLSL shaders: yes Texture NPOT support: yes Virtual Machine: no OpenGL 2 Shaders are used Loaded Effects: --------------- kwin4_effect_fullscreen kwin4_effect_windowaperture kwin4_effect_squash kwin4_effect_sessionquit kwin4_effect_scale kwin4_effect_morphingpopups kwin4_effect_maximize kwin4_effect_logout kwin4_effect_login kwin4_effect_frozenapp kwin4_effect_fadingpopups kwin4_effect_dialogparent colorpicker outputlocator blendchanges screenshot screenedge zoom slidingpopups slide highlightwindow overview blur contrast startupfeedback kscreen Currently Active Effects: ------------------------- blur contrast Effect Settings: ---------------- kwin4_effect_fullscreen: pluginId: kwin4_effect_fullscreen isActiveFullScreenEffect: false kwin4_effect_windowaperture: pluginId: kwin4_effect_windowaperture isActiveFullScreenEffect: false kwin4_effect_squash: pluginId: kwin4_effect_squash isActiveFullScreenEffect: false kwin4_effect_sessionquit: pluginId: kwin4_effect_sessionquit isActiveFullScreenEffect: false kwin4_effect_scale: pluginId: kwin4_effect_scale isActiveFullScreenEffect: false kwin4_effect_morphingpopups: pluginId: kwin4_effect_morphingpopups isActiveFullScreenEffect: false kwin4_effect_maximize: pluginId: kwin4_effect_maximize isActiveFullScreenEffect: false kwin4_effect_logout: pluginId: kwin4_effect_logout isActiveFullScreenEffect: false kwin4_effect_login: pluginId: kwin4_effect_login isActiveFullScreenEffect: false kwin4_effect_frozenapp: pluginId: kwin4_effect_frozenapp isActiveFullScreenEffect: false kwin4_effect_fadingpopups: pluginId: kwin4_effect_fadingpopups isActiveFullScreenEffect: false kwin4_effect_dialogparent: pluginId: kwin4_effect_dialogparent isActiveFullScreenEffect: false colorpicker: outputlocator: blendchanges: screenshot: screenedge: zoom: zoomFactor: 1.2 mousePointer: 0 mouseTracking: 0 focusTrackingEnabled: false textCaretTrackingEnabled: false focusDelay: 350 moveFactor: 20 targetZoom: 1 slidingpopups: slideInDuration: 75 slideOutDuration: 125 slide: horizontalGap: 45 verticalGap: 20 slideDocks: false slideBackground: true highlightwindow: overview: activeView: animationDuration: 150 layout: 1 ignoreMinimized: false blurBackground: true partialActivationFactor: 0 gestureInProgress: false searchText: blur: contrast: startupfeedback: type: 1 kscreen: Loaded Plugins: --------------- kwin5_plugin_krunner kwin5_plugin_nightcolor Available Plugins: ------------------ kwin5_plugin_buttonrebinds kwin5_plugin_colord kwin5_plugin_krunner kwin5_plugin_nightcolor
Just to clarify, stuttering happens even if I use the stock Breeze Window decoration, rather than an aurorae one.
What's kwin's cpu usage when the system is laggy?
CPU is fine. The problem I believe is related to other bugs that have already been submitted regarding compositing. Everytime something affects compositing (e.g., it disables it, think of a game), makes kwin unresponsive. This happens only when having another monitor attached to the laptop. Without external monitors, everything is fine.
See for example: https://bugs.kde.org/show_bug.cgi?id=426412