Oooh... that makes sense now, thanks. The problem you are seeing is with mutter/gnome-shell being inefficient at frequently-updating software rendered windows. This is a known problem, but until now we only knew of Eclipse triggering it (bug 1756508), and the older pre-Quantum versions of Firefox (bug 1696305).
What you are seeing is a known performance problem, but you have discovered a great test case for it in the Resources tab. So thanks. As I suspected, this is not a problem with the new Firefox at all (which is hardware rendered). It's a problem with gnome-system-monitor, or any frequently-redrawing software rendered (e.g. Gnome) app. I only have two more questions: What is your display resolution, and are you using Wayland or Xorg? Both of these can be answered by running 'xrandr' and sending us the output. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-shell in Ubuntu. https://bugs.launchpad.net/bugs/1773502 Title: High CPU usage in gnome-shell & Xorg when using gnome-system-monitor's Resources tab Status in gnome-shell package in Ubuntu: Triaged Bug description: gnome-shell or X.org using high cpu My fanless nettop use a Intel Celeron 847 CPU. On around 1 boot on 3, the CPU of one core is kept at 100 % by a process, this high CPU usage start few second after the boot. It seems related to the graphical system. ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: gnome-shell 3.28.1-0ubuntu2 ProcVersionSignature: Ubuntu 4.15.0-22.24-generic 4.15.17 Uname: Linux 4.15.0-22-generic x86_64 ApportVersion: 2.20.9-0ubuntu7 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Sat May 26 09:52:20 2018 DisplayManager: gdm3 GsettingsChanges: b'org.gnome.shell' b'app-picker-view' b'uint32 1' b'org.gnome.shell' b'favorite-apps' redacted by apport b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'" b'org.gnome.desktop.interface' b'clock-show-date' b'true' InstallationDate: Installed on 2018-04-29 (26 days ago) InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=fr_BE.UTF-8 SHELL=/bin/bash SourcePackage: gnome-shell UpgradeStatus: No upgrade log present (probably fresh install) --- ApportVersion: 2.20.9-0ubuntu7 Architecture: amd64 CurrentDesktop: ubuntu:GNOME DisplayManager: gdm3 DistroRelease: Ubuntu 18.04 GsettingsChanges: b'org.gnome.shell' b'app-picker-view' b'uint32 1' b'org.gnome.shell' b'favorite-apps' redacted by apport b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'" b'org.gnome.desktop.interface' b'clock-show-date' b'true' InstallationDate: Installed on 2018-04-29 (26 days ago) InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) Package: gnome-shell 3.28.1-0ubuntu2 PackageArchitecture: amd64 ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=fr_BE.UTF-8 SHELL=/bin/bash ProcVersionSignature: Ubuntu 4.15.0-22.24-generic 4.15.17 Tags: bionic Uname: Linux 4.15.0-22-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1773502/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
