cinnamon --replace high cpu load ~30% libvirt/kvm with qxl/spice

Distribution

Mint 22.1

Package version

6.4.8

Graphics hardware in use

Red Hat, Inc. QXL paravirtual graphic card // Spice

Frequency

Always

Bug description

A fresh installed Mint 22.1 with QXL paravirtual graphic card in a libvirt/KVM VM uses a lot of CPU load.

Steps to reproduce

Install Mint 22.1 in libvirt/KVM VM and use QXL as graphic card.
If I use remote-viewer with spice and multiple displays the cpu-load rises way more.
Installed virtio/kvm/qxl/spice related packages:
- xserver-xorg-video-qxl
- spice-vdagent
- qemu-guest-agent
- virtiofsd
- linux-image-virtual

Expected behavior

No such high CPU load. On other systems the CPU-load of "cinnamon --replace" is way lower.

Additional information

rised Video-mem to:

<video>
  <model type="qxl" ram="524288" vram="262144" vgamem="262144" heads="3" primary="yes"/>
  <alias name="video0"/>
  <address type="pci" domain="0x0000" bus="0x00" slot="0x01" function="0x0"/>
</video>

.xsession-errors says

dbus-update-activation-environment: setting DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus
dbus-update-activation-environment: setting DISPLAY=:0
dbus-update-activation-environment: setting XAUTHORITY=/home/olb/.Xauthority
/etc/X11/Xsession.d/30x11-common_xresources: Zeile 16: has_option: Befehl nicht gefunden
/etc/X11/Xsession.d/75dbus_dbus-launch: Zeile 9: has_option: Befehl nicht gefunden
dbus-update-activation-environment: setting GTK_MODULES=gail:atk-bridge
dbus-update-activation-environment: setting QT_ACCESSIBILITY=1
/etc/X11/Xsession.d/90x11-common_ssh-agent: Zeile 9: has_option: Befehl nicht gefunden
dbus-update-activation-environment: setting SHELL=/bin/bash
dbus-update-activation-environment: setting QT_ACCESSIBILITY=1
dbus-update-activation-environment: setting XDG_CONFIG_DIRS=/etc/xdg/xdg-cinnamon:/etc/xdg
dbus-update-activation-environment: setting HISTSIZE=
dbus-update-activation-environment: setting LANGUAGE=de_DE
dbus-update-activation-environment: setting HISTTIMEFORMAT=[%F %T] 
dbus-update-activation-environment: setting DESKTOP_SESSION=cinnamon
dbus-update-activation-environment: setting EDITOR=/usr/bin/vim
dbus-update-activation-environment: setting GTK_MODULES=gail:atk-bridge
dbus-update-activation-environment: setting PWD=/home/olb
dbus-update-activation-environment: setting XDG_SESSION_DESKTOP=cinnamon
dbus-update-activation-environment: setting LOGNAME=olb
dbus-update-activation-environment: setting XDG_SESSION_TYPE=x11
dbus-update-activation-environment: setting GPG_AGENT_INFO=/run/user/1000/gnupg/S.gpg-agent:0:1
dbus-update-activation-environment: setting XAUTHORITY=/home/olb/.Xauthority
dbus-update-activation-environment: setting XDG_GREETER_DATA_DIR=/var/lib/lightdm-data/olb
dbus-update-activation-environment: setting GDM_LANG=de_DE
dbus-update-activation-environment: setting HOME=/home/olb
dbus-update-activation-environment: setting IM_CONFIG_PHASE=1
dbus-update-activation-environment: setting LANG=de_DE.UTF-8
dbus-update-activation-environment: setting XDG_SESSION_CLASS=user
dbus-update-activation-environment: setting LIBVIRT_DEFAULT_URI=qemu:///system
dbus-update-activation-environment: setting USER=olb
dbus-update-activation-environment: setting DISPLAY=:0
dbus-update-activation-environment: setting SHLVL=0
dbus-update-activation-environment: setting XDG_RUNTIME_DIR=/run/user/1000
dbus-update-activation-environment: setting GTK3_MODULES=xapp-gtk3-module
dbus-update-activation-environment: setting XDG_DATA_DIRS=/usr/share/cinnamon:/usr/share/gnome:/home/olb/.local/share/flatpak/exports/share:/var/lib/flatpak/exports/share:/usr/local/share:/usr/share
dbus-update-activation-environment: setting PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
dbus-update-activation-environment: setting GDMSESSION=cinnamon
dbus-update-activation-environment: setting HISTFILESIZE=
dbus-update-activation-environment: setting DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus
dbus-update-activation-environment: setting DEBIAN_FRONTEND=noninteractive
dbus-update-activation-environment: setting _=/usr/bin/dbus-update-activation-environment
discover_other_daemon: 1discover_other_daemon: 1discover_other_daemon: 1[cinnamon-settings-daemon-smartcard] Failed to start: no suitable smartcard driver could be found
[cinnamon-settings-daemon-smartcard] Failed to start: no suitable smartcard driver could be found
dbus-daemon[2965]: Activating service name='org.a11y.atspi.Registry' requested by ':1.0' (uid=1000 pid=2936 comm="/usr/bin/csd-clipboard" label="unconfined")
dbus-daemon[2965]: Successfully activated service 'org.a11y.atspi.Registry'
/usr/bin/cinnamon-launcher:56: DeprecationWarning: This process (pid=3065) is multi-threaded, use of fork() may lead to deadlocks in the child.
  self.cinnamon_pid = os.fork()
Xlib:  extension "DPMS" missing on display ":0".
Xlib:  extension "DPMS" missing on display ":0".
Gjs-Message: 09:12:55.888: Profiler is disabled. Not setting up signals.
Gjs-Message: 09:12:56.070: JS LOG: About to start Cinnamon (X11 backend)
Gjs-Message: 09:12:56.147: JS LOG: [LookingGlass/info] Cinnamon.AppSystem.get_default() started in 0 ms
Gjs-Message: 09:12:56.149: JS LOG: [LookingGlass/info] loading user theme: /usr/share/themes/Mint-Y-Dark/cinnamon/cinnamon.css
Gjs-Message: 09:12:56.161: JS LOG: [LookingGlass/info] added icon directory: /usr/share/themes/Mint-Y-Dark/cinnamon
Gjs-Message: 09:12:56.300: JS LOG: [LookingGlass/info] NetworkManager agent: enabled
Gjs-Message: 09:12:56.310: JS LOG: [LookingGlass/info] Polkit agent: enabled
Gjs-Message: 09:12:56.311: JS LOG: [LookingGlass/info] SSH agent: enabled
Gjs-Message: 09:12:56.327: JS LOG: [LookingGlass/info] loaded at Wed Jul 02 2025 09:12:56 GMT+0200 (Mitteleuropäische Sommerzeit)
Gjs-Message: 09:12:56.327: JS LOG: Cinnamon started at Wed Jul 02 2025 09:12:56 GMT+0200 (Mitteleuropäische Sommerzeit)
Gjs-Message: 09:12:56.341: JS LOG: [LookingGlass/info] ExtensionSystem started in 1 ms
Gjs-Message: 09:12:56.341: JS LOG: [LookingGlass/info] DeskletManager started in 1 ms
Gjs-Message: 09:12:56.341: JS LOG: [LookingGlass/info] SearchProviderManager started in 1 ms
Xlib:  extension "DPMS" missing on display ":0".

(csd-color:2958): csd-color-WARNING **: 09:12:56.396: failed to get edid: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:12:56.408: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output
Gjs-Message: 09:12:56.456: JS LOG: [LookingGlass/info] Loaded applet show-desktop@cinnamon.org in 42 ms
Gjs-Message: 09:12:56.482: JS LOG: [LookingGlass/info] Loaded applet keyboard@cinnamon.org in 26 ms
Gjs-Message: 09:12:56.494: JS LOG: [LookingGlass/info] Role locked: notifications
Gjs-Message: 09:12:56.512: JS LOG: [LookingGlass/info] Loaded applet notifications@cinnamon.org in 30 ms

** (at-spi2-registryd:2999): WARNING **: 09:12:56.585: Failed to register client: GDBus.Error:org.gnome.SessionManager.AlreadyRegistered: Unable to register client

** (at-spi2-registryd:2999): WARNING **: 09:12:56.585: Unable to register client with session manager
Cannot register authentication agent: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: An authentication agent already exists for the given subject
Gjs-Message: 09:12:56.629: JS LOG: [LookingGlass/info] Loaded applet user@cinnamon.org in 117 ms
Gjs-Message: 09:12:56.658: JS LOG: [LookingGlass/info] Role locked: tray
Gjs-Message: 09:12:56.672: JS LOG: [LookingGlass/info] Loaded applet systray@cinnamon.org in 43 ms
Gjs-Message: 09:12:56.704: JS LOG: [LookingGlass/info] Loaded applet removable-drives@cinnamon.org in 32 ms
Gjs-Message: 09:12:56.795: JS LOG: [LookingGlass/info] Loaded applet calendar@cinnamon.org in 91 ms
Gjs-Message: 09:12:56.856: JS LOG: [LookingGlass/info] Loaded applet printers@cinnamon.org in 60 ms
Gjs-Message: 09:12:56.893: JS LOG: [LookingGlass/info] Loaded applet xapp-status@cinnamon.org in 37 ms
Gjs-Message: 09:12:56.973: JS LOG: [LookingGlass/info] Role locked: panellauncher
Gjs-Message: 09:12:56.986: JS LOG: [LookingGlass/info] Loaded applet panel-launchers@cinnamon.org in 93 ms
Gjs-Message: 09:12:57.053: JS LOG: [LookingGlass/info] Loaded applet power@cinnamon.org in 67 ms
Gjs-Message: 09:12:57.098: JS LOG: [LookingGlass/info] Role locked: windowattentionhandler
Nemo-Message: 09:12:57.108: nemo-desktop: session is cinnamon, establishing proxy
Gjs-Message: 09:12:57.110: JS LOG: [LookingGlass/info] Loaded applet window-list@cinnamon.org in 57 ms
Gjs-Message: 09:12:57.114: JS LOG: calendar@cinnamon.org: Calendar events supported.
Gjs-Message: 09:12:57.159: JS LOG: [LookingGlass/info] Loaded applet sound@cinnamon.org in 49 ms
blueman-applet 09.12.57 WARNING  PluginManager:150 __load_plugin: Not loading PPPSupport because its conflict has higher priority
blueman-applet 09.12.57 WARNING  PluginManager:150 __load_plugin: Not loading DhcpClient because its conflict has higher priority
Gjs-Message: 09:12:57.324: JS LOG: [LookingGlass/info] Loaded applet menu@cinnamon.org in 165 ms
Gjs-Message: 09:12:57.336: JS LOG: [LookingGlass/info] Loaded applet network@cinnamon.org in 12 ms
Gjs-Message: 09:12:57.336: JS LOG: [LookingGlass/info] AppletManager started in 1007 ms
Gjs-Message: 09:12:57.341: JS LOG: [LookingGlass/info] Cinnamon took 1271 ms to start
Gjs-Message: 09:12:57.411: JS LOG: Unknown network device type, is 32
Gjs-Message: 09:12:57.415: JS LOG: Unknown network device type, is 13

(cinnamon:3110): XApp-CRITICAL **: 09:12:57.588: Could not get gpu info from switcheroo proxy: (0): No default GPU exists.

(cinnamon:3110): GLib-GIO-CRITICAL **: 09:12:57.588: g_task_return_boolean: assertion '!task->ever_returned' failed
Gjs-Message: 09:12:57.598: JS LOG: [LookingGlass/info] GPU offload supported: false
Gjs-Message: 09:13:01.531: JS LOG: Enabling WindowAttentionHandler
Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x4200003
Xlib:  extension "DPMS" missing on display ":0".

(cinnamon:3110): mutter-WARNING **: 09:13:07.900: Impossible to set scaling on crtc 62 to 1,000000, error id 2
Window manager warning: Scalig CRTC 62 at 1,000000 failed
Xlib:  extension "DPMS" missing on display ":0".
Xlib:  extension "DPMS" missing on display ":0".

(csd-color:2958): csd-color-WARNING **: 09:13:08.218: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:08.255: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output
Xlib:  extension "DPMS" missing on display ":0".

(cinnamon:3110): mutter-WARNING **: 09:13:12.065: Impossible to set scaling on crtc 62 to 1,000000, error id 2
Window manager warning: Scalig CRTC 62 at 1,000000 failed

(cinnamon:3110): mutter-WARNING **: 09:13:12.079: Impossible to set scaling on crtc 63 to 1,000000, error id 2
Window manager warning: Scalig CRTC 63 at 1,000000 failed
Xlib:  extension "DPMS" missing on display ":0".
Xlib:  extension "DPMS" missing on display ":0".

(csd-color:2958): csd-color-WARNING **: 09:13:12.651: failed to get edid: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:12.665: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:12.700: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:12.713: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:12.787: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:12.788: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output
Xlib:  extension "DPMS" missing on display ":0".

(cinnamon:3110): mutter-WARNING **: 09:13:15.747: Impossible to set scaling on crtc 62 to 1,000000, error id 2
Window manager warning: Scalig CRTC 62 at 1,000000 failed

(cinnamon:3110): mutter-WARNING **: 09:13:15.756: Impossible to set scaling on crtc 63 to 1,000000, error id 2
Window manager warning: Scalig CRTC 63 at 1,000000 failed
Xlib:  extension "DPMS" missing on display ":0".
Xlib:  extension "DPMS" missing on display ":0".

(csd-color:2958): csd-color-WARNING **: 09:13:16.402: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:16.536: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:16.538: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:16.539: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output
Xlib:  extension "DPMS" missing on display ":0".

(cinnamon:3110): mutter-WARNING **: 09:13:19.142: Impossible to set scaling on crtc 62 to 1,000000, error id 2
Window manager warning: Scalig CRTC 62 at 1,000000 failed

(cinnamon:3110): mutter-WARNING **: 09:13:19.162: Impossible to set scaling on crtc 63 to 1,000000, error id 2
Window manager warning: Scalig CRTC 63 at 1,000000 failed

(cinnamon:3110): mutter-WARNING **: 09:13:19.925: Impossible to set scaling on crtc 64 to 1,000000, error id 2
Window manager warning: Scalig CRTC 64 at 1,000000 failed
Xlib:  extension "DPMS" missing on display ":0".
Xlib:  extension "DPMS" missing on display ":0".
Xlib:  extension "DPMS" missing on display ":0".

(csd-color:2958): csd-color-WARNING **: 09:13:20.830: failed to get edid: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:20.859: unable to get EDID for xrandr-Virtual-3: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:20.994: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output
sys:1: Warning: ../../../gobject/gsignal.c:2685: instance '0x5b67b90db610' has no handler with id '7986'

(csd-color:2958): csd-color-WARNING **: 09:13:21.096: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:21.226: unable to get EDID for xrandr-Virtual-3: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:21.228: unable to get EDID for xrandr-Virtual-3: unable to get EDID for output
Gjs-Message: 09:13:21.228: JS LOG: [LookingGlass/info] Adding XAppStatusIcon: mintUpdate.py (:1.91/org/x/StatusIcon/Icon)

(csd-color:2958): csd-color-WARNING **: 09:13:21.318: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output
Xlib:  extension "DPMS" missing on display ":0".
blueman-applet 09.13.22 WARNING  DiscvManager:122 update_menuitems: warning: Adapter is None

(cinnamon:3110): mutter-WARNING **: 09:13:25.482: Impossible to set scaling on crtc 62 to 1,000000, error id 2
Window manager warning: Scalig CRTC 62 at 1,000000 failed

(cinnamon:3110): mutter-WARNING **: 09:13:25.495: Impossible to set scaling on crtc 63 to 1,000000, error id 2
Window manager warning: Scalig CRTC 63 at 1,000000 failed

(cinnamon:3110): mutter-WARNING **: 09:13:26.337: Impossible to set scaling on crtc 64 to 1,000000, error id 2
Window manager warning: Scalig CRTC 64 at 1,000000 failed
Xlib:  extension "DPMS" missing on display ":0".
Xlib:  extension "DPMS" missing on display ":0".
Xlib:  extension "DPMS" missing on display ":0".

(csd-color:2958): csd-color-WARNING **: 09:13:27.271: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:27.275: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:27.283: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:27.288: unable to get EDID for xrandr-Virtual-3: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:27.984: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:28.193: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:28.566: unable to get EDID for xrandr-Virtual-3: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:28.676: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:28.770: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:28.771: unable to get EDID for xrandr-Virtual-3: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:28.772: unable to get EDID for xrandr-Virtual-1: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:28.773: unable to get EDID for xrandr-Virtual-2: unable to get EDID for output

(csd-color:2958): csd-color-WARNING **: 09:13:28.775: unable to get EDID for xrandr-Virtual-3: unable to get EDID for output
Gjs-Message: 09:13:41.008: JS LOG: [LookingGlass/info] Adding XAppStatusIcon: mintreport (:1.103/org/x/StatusIcon/Icon)
Gjs-Message: 09:13:41.011: JS LOG: [LookingGlass/info] Adding XAppStatusIcon: process-monitor (:1.103/org/x/StatusIcon/Icon_1)
Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x4200003

Reproduce the high CPU usage in Mint 22.1 running Cinnamon 6.4.8 inside a libvirt/KVM VM with QXL and SPICE, comparing single and multiple displays. Start with the cinnamon process and the supplied .xsession-errors output; done means identifying a Cinnamon-side cause or a reproducible limitation and documenting a verified reduction in CPU load.