bug#44818: 27.0.91; wedged

[Devon Sean McCullough]

On 24/11/2020 13:48, Eli Zaretskii wrote:
> > Cc: 44818@debbugs.gnu.org
> > From: Devon Sean McCullough <Emacs-hacker2018@jovi.net>
> > Date: Tue, 24 Nov 2020 13:42:03 -0500
> >
> > P.S.  Could a watchdog timer safely abort such wedgitude?
>
> That would have to run in a separate thread, right?
>
> But what timeout to set it to? some jobs might legitimately take some
> time.  And then what to do when the timer expires?

The job of redisplay cannot legitimately take > 50 milliseconds.
When the user repeatedly tries ^G quit but Emacs is unresponsive
because of redisplay, such redisplay must be prevented while the
user is offered options to regain control.

                Peace
                        --Devon

P.S. Could an invisibility overlay offer temporary relief?
Perhaps a red screen of redisplay death with a short menu?