The GNOME Shell Calendar Will Stop Over-Consuming The CPU, Eating Up Battery Life

For the past five months there has been a bug report affecting the likes of Pop OS 19.10 and Fedora 31 over the GNOME Shell Calendar server using "20~25% CPU all the time" and "every 2-3 seconds or so there is a CPU usage spike where the calendar processes eat something like 20-25% of the CPU." That is significant on modern CPUs as well as on battery life for laptops while finally the issue has been fixed.

The five month old bug report has been tracked in calendar-server: Constantly restarts ECalClientView-s. Within there is plenty of detailed information on the GNOME Shell calendar-server problem, flame graphs, and confirmation of it affecting multiple users. Patches to address the issue have been available for a few weeks but only merged today.

This merge pulled into GNOME Shell today improves the performance by properly using ECalClientView. Milan Crha explained, "The previous code always restarted whole ECalClientView when it received any changes in it, which could sometimes lead to constant repeated restarts of the view."

With those repeated restarts avoided, the GNOME Shell Calendar should stop consuming so much of the CPU. This fix should appear in the next GNOME Shell point release.