After years of high CPU usage with gnome-shell and not finding the issue, I finally found this bug report, disable showing the seconds of the clock in the top panel and now the CPU usage is between 0-1% instead of 40% and more. What the heck? Thank you!
Still clock_gettime is active 71% of the time but the overall usage is no minimal. Maybe my battery will last longer now. -- 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/1773959 Title: High CPU usage by gnome-shell when only running gnome-terminal Status in gnome-shell package in Ubuntu: Incomplete Bug description: Even when doing nothing but displaying a terminal screen with top running gnome-shell uses 10% of a CPU. That seems excessive. I disabled all extensions to try and make the test fair. Enabling the system monitor extension increases the load to 13-14%. It seems that the gnome-shell screen painting is highly CPU consuming even if screen updates are infrequent (1 a second for all these cases). ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: gnome-shell 3.28.1-0ubuntu2 ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17 Uname: Linux 4.15.0-20-generic x86_64 ApportVersion: 2.20.9-0ubuntu7 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Tue May 29 11:38:05 2018 DisplayManager: gdm3 InstallationDate: Installed on 2016-10-27 (578 days ago) InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719) SourcePackage: gnome-shell UpgradeStatus: Upgraded to bionic on 2018-05-19 (9 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1773959/+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