Bug 450566

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