Bug 438297

SUMMARY
The kwin_x11 process takes up abnormally high amount of cpu ressources (up to 60% as reported by htop when watching a 720p video on a good system) but the problem seems to fade away when logging out and logging back in. This happens when disabling all the scripts, effects and addons I could find

STEPS TO REPRODUCE
1. Boot up the computer

OBSERVED RESULT
System is sluggish, kwin_x11 uses crazy high amount of cpu

EXPECTED RESULT
Low (sub 10%) cpu usage. Is achieved after logging out and back in

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 5.21.5
KDE Frameworks Version: Not sure? Latest from GNU/Arch Linux
Qt Version: 5.15.2

ADDITIONAL INFORMATION
Please find the output of `qdbus org.kde.KWin /KWin supportInformation` below

```
KWin Support Information:
The following information should be used when requesting support on e.g. https://forum.kde.org.
It provides information about the currently running instance, which options are used,
what OpenGL driver and which effects are running.
Please post the information provided underneath this introductory text to a paste bin service
like https://paste.kde.org instead of pasting into support threads.

==========================

Version
=======
KWin version: 5.21.5
Qt Version: 5.15.2
Qt compile version: 5.15.2
XCB compile version: 1.14

Operation Mode: X11 only

Build Options
=============
KWIN_BUILD_DECORATIONS: yes
KWIN_BUILD_TABBOX: yes
KWIN_BUILD_ACTIVITIES: yes
HAVE_DRM: yes
HAVE_GBM: yes
HAVE_EGL_STREAMS: yes
HAVE_X11_XCB: yes
HAVE_EPOXY_GLX: yes
HAVE_WAYLAND_EGL: yes

X11
===
Vendor: The X.Org Foundation
Vendor Release: 12011000
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.breeze
Theme: 
Plugin recommends border size: None
Blur: 0
onAllDesktopsAvailable: true
alphaChannelSupported: true
closeOnDoubleClickOnMenu: false
decorationButtonsLeft: 5, 3, 4, 7
decorationButtonsRight: 0
borderSize: 0
gridUnit: 10
font: IBM Plex Sans,10,-1,5,50,0,0,0,0,0,Regular
smallSpacing: 2
largeSpacing: 10

Platform
==========
Name: KWin::X11StandalonePlatform

Cursor
======
themeName: OpenZone_Black_Slim
themeSize: 24

Options
=======
focusPolicy: 0
xwaylandCrashPolicy: 
xwaylandMaxCrashCount: 3
nextFocusPrefersMouse: false
clickRaise: true
autoRaise: false
autoRaiseInterval: 0
delayFocusInterval: 0
shadeHover: false
shadeHoverInterval: 250
separateScreenFocus: true
placement: 8
focusPolicyIsReasonable: true
borderSnapZone: 10
windowSnapZone: 10
centerSnapZone: 0
snapOnlyWhenOverlapping: false
rollOverDesktops: true
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: 16777251
showGeometryTip: false
condensedTitle: false
electricBorderMaximize: true
electricBorderTiling: true
electricBorderCornerRatio: 0.25
borderlessMaximizedWindows: false
killPingTimeout: 5000
hideUtilityWindowsForInactive: true
compositingMode: 1
useCompositing: true
hiddenPreviews: 1
glSmoothScale: 1
xrenderSmoothScale: false
glStrictBinding: true
glStrictBindingFollowsDriver: true
glCoreProfile: false
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
=======
Multi-Head: no
Active screen follows mouse:  no
Number of Screens: 2

Screen 0:
---------
Name: DVI-D-0
Geometry: 1920,0,1920x1080
Scale: 1
Refresh Rate: 59.933

Screen 1:
---------
Name: HDMI-0
Geometry: 0,0,1920x1080
Scale: 1
Refresh Rate: 60


Compositing
===========
Compositing is active
Compositing Type: OpenGL
OpenGL vendor string: Mesa/X.org
OpenGL renderer string: llvmpipe (LLVM 12.0.0, 256 bits)
OpenGL version string: 3.1 Mesa 21.1.2
OpenGL platform interface: GLX
OpenGL shading language version string: 1.40
Driver: LLVMpipe
GPU class: Unknown
OpenGL version: 3.1
GLSL version: 1.40
Mesa version: 21.1.2
X server version: 1.20.11
Linux kernel version: 5.12.9
Direct rendering: Requires strict binding: yes
GLSL shaders:  yes
Texture NPOT support:  yes
Virtual Machine:  no
OpenGL 2 Shaders are used

Loaded Effects:
---------------
screenshot
colorpicker
highlightwindow
startupfeedback
kscreen

Currently Active Effects:
-------------------------

Effect Settings:
----------------
screenshot:

colorpicker:

highlightwindow:

startupfeedback:
type: 1

kscreen:


Loaded Plugins:
---------------
kwin5_plugin_krunner
kwin5_plugin_nightcolor

Available Plugins:
------------------
kwin5_plugin_colord
kwin5_plugin_krunner
kwin5_plugin_nightcolor

```