I checked my journalctl logs and they are similar to yours. I don’t see a problem there.
A few things to check:
(You can paste the results of these commands here…)
1. Which process is eating up your CPU?
Check which process is using the CPU. Look at the Conky (default one shows process lists), run btop, top, lxtask or the following command:
ps -eo pid,ppid,cmd,%mem,%cpu --sort=-%cpu | head
2. Full disk?
Check the disk usage and whether it is full
df -kh
3. Enable fstrim if you use solid-state-drive
If you use SSD (solid-state drives) or NVMe disc, then enable fstrim service.