Comment # 6 on bug 1193931 from Takashi Iwai

(In reply to Artyom from comment #5)
> (In reply to Takashi Iwai from comment #3)
> > Could you give hwinfo output?
> 
> Done
> 
> (In reply to Takashi Iwai from comment #3)
> > There is nothing serious shown in the kernel itself, so it's hard to judge
> > only from the current log, unfortunately.
> 
> How can I get more information if this happens again? (fortunately, this
> does not happen often)
> Perhaps with the 5.16 kernel it will be fixed
> 
> (In reply to Takashi Iwai from comment #3)
> > What is the a.out at the end of the log?  There seems to be lots of
> > segfaults happening there (the suppressed show_signal_msg).
> 
> Its buggy application (there off-by-one bug)
> I think problem in iwlwifi driver

Possible.  But usually WiFi driver problem shouldn't bring such a slowdown.

Is the slowdown phenomenon reproducible?  I wonder whether it was due to the
massive crashes (segfaults) of buggy application you mentioned in the above. 
Since each crash triggers the core dump and processing via systemd-coredump,
it'll take lots of CPU and storage resources.