Ubuntu – How to stop the ‘Free the Fish’ Easter Egg

You just need to install gnome-shell. And it is as simple as

sudo apt-get install gnome-shell

I have had similar consistent high CPU load on gnome-shell for no clear reason since installing 18.04. I figured it was just obscuring something under the hood like firefox video rendering, but it also doesn't really go down anywhere near zero even with every program closed and even without moving the mouse.

I tried the same strace and get similar results:

% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 39.61    0.240174           3     87585     76642 recvmsg
 25.36    0.153778           6     27384           poll
  9.07    0.054990           3     17502           ioctl
  8.98    0.054434           3     18079           write
  7.98    0.048402           5      9702           writev
  3.29    0.019926           3      6640           read
  2.20    0.013369           1      8942           getpid
  1.32    0.008014           6      1352        59 futex
  0.91    0.005530           2      2634           mprotect
  0.23    0.001413          20        72           mmap
  0.21    0.001299           4       353           close
  0.21    0.001272           5       240           timerfd_create
  0.17    0.001043          10       101         2 openat
  0.17    0.001010           4       240           timerfd_settime
  0.09    0.000518           1       420       360 stat
  0.07    0.000432           2       198           fstat
  0.06    0.000374           9        41           munmap
  0.03    0.000192           2       124           getrusage
  0.03    0.000184           2        99           fcntl
  0.00    0.000006           2         4           recvfrom
  0.00    0.000004           1         7           sendmsg
  0.00    0.000004           1         7           ftruncate
  0.00    0.000004           1         7           memfd_create
  0.00    0.000003           2         2           uname
  0.00    0.000001           0         7           lseek
  0.00    0.000000           0         1           restart_syscall
------ ----------- ----------- --------- --------- ----------------
100.00    0.606376                181743     77063 total

It's pretty bad, I have stuttering at about a 1 sec interval across all my programs. It's so consistent I've gotten used to compensating for it. Video playback stutters, games stutter, firefox stutters, it's pretty annoying. No idea where to start on fixing it, though killing gnome-shell and restarting it at least works for a while -- still with the errors, but more responsive.

Side bar on the left often also glitches with overlapping icons and the like, I suspect there's some cumulative errors gnome-shell gets into and that at some point it is spending a lot of CPU time trying to resolve badly interacting contradictions between some configuration or edge case or something. I guess at this point I'll just hope 18.10 is any better.