How to find the cause for high CPU usage of gnome-shell?
Solution 1:
Perhaps try using auditd, which would roughly be something like:
sudo yum install auditd # sudo apt install auditd on Debian
sudo auditctl -a exit,always -S all -F pid=1234 & sleep 15
sudo auditctl -d exit,always -S all -F pid=1234
less /var/log/audit/audit.log
This will install and start auditd, set a policy to capture system call info for your PID (1234 in the example), wait for a short while to capture a decent amount of info, then remove the audit policy. Take a good look over the auditd.log for your gnome-terminal PID, you may get a better idea of what it's busy doing.
Another quick tool for spotting what a process is spending it's time doing is just strace, wait a short time, then hit Ctrl + C:
$ sudo strace -c -p 1234
strace: Process 1234 attached
^Cstrace: Process 1234 detached
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
56.98 0.003496 388 9 clone
17.19 0.001055 8 135 rt_sigprocmask
6.19 0.000380 21 18 9 wait4
4.58 0.000281 16 18 close
3.80 0.000233 26 9 read
3.47 0.000213 24 9 stat
3.37 0.000207 23 9 9 rt_sigsuspend
3.08 0.000189 21 9 pipe
1.34 0.000082 9 9 9 rt_sigreturn
------ ----------- ----------- --------- --------- ----------------
100.00 0.006136 225 27 total
Then if you want to learn more, check the appropriate man page for the system call you're looking at:
$ man -s2 clone
Solution 2:
There could be several causes of it:
- clock with seconds
gsettings set org.gnome.desktop.interface clock-show-seconds false
- indicator-multiload (CPU etc. usage monitor in bar)
Process could be named in menu: System Load Indicator
Just stop process (or before stopping it, disable autostart option. Setting longer time for probing also helps, but for example 10 sec. makes whole app useless.
- anything with "real time" monitoring, disk, cpu, network