`jobs` shows too high CPU usage

[septatrix]

The output of jobs sometimes shows much too high CPU usage stats for background jobs.
It seems somewhat racy as for processes with normal usage it is either very high or 0%. yes seems to always show a too high result.

• fish, version 3.4.1
• 5.16.19-200.fc35.x86_64 (Fedora 35)

~ $ yes >/dev/null &
~ $ jobs
Job	Group	CPU	State	Command
1	1324566	99039434%	running	yes >/dev/null &
~ $ ps -p $last_pid -o %cpu,cmd
%CPU CMD
99.3 yes

[ridiculousfish]

Nice find. Bisects to 7a1c005.