bug#20285: 25.0.50; blink-cursor-mode sometimes stops blinking

[Tassilo Horn <tsdh@gnu.org>]

Stefan Monnier <monnier@IRO.UMontreal.CA> writes:

> I haven't followed this discussion very closely, but I can't see
> anywhere in this thread where we have data that really confirms that
> the problem was that redisplay was skipped because of other needed
> activities.

I can at least confirm that `blink-cursor-timer-function' runs every 0.5
seconds and toggles the visibility state of the cursor.  When that state
doesn't appear on the screen, then what else can it be except for a
skipped redisplay.

Maybe the interval is 0.8 seconds sometimes when emacs is under heavy
load.  But the timer not being run is definitely not the cause for not
blinking for up to 10 seconds here.

> Have you tried to call `redisplay' explicitly from the blink-cursor
> timer?

Yes, then it blinks fine even under stress.

Bye,
Tassilo