Re: Blink cursor changes, possible W32 breakage.

[Eli Zaretskii <eliz@gnu.org>]

> From: Jan Djärv <jan.h.d@swipnet.se>
> Date: Wed, 17 Jul 2013 09:38:32 +0200
> Cc: Eli Zaretskii <eliz@gnu.org>,
>  emacs-devel@gnu.org
> 
> > Eli Zaretskii <eliz@gnu.org> writes:
> >> If you only stop the timers that blink the cursor, then this isn't
> >> going to fix the problem.  There's any number of timers active at
> >> any given time in any non-trivial Emacs session.  You need to stop
> >> them all, or the battery drain will continue.
> > 
> 
> We can't know what other timers do, in general.  Maybe they are supposed to run some Elisp in the background and/or when the frame has no focus.  In contrast, we know very well what blinking timers are supposed to do, so we have control over those.

But if you stop one timer, but leave the other N running, what did you
accomplish, exactly, in terms of allowing the laptop stop using
battery power and perhaps swap Emacs out of RAM?

> > Is it _timers_ that cause battery drain, or _timers firing_?  I'd
> > imagine that with a reasonable implementation, it would be the
> > latter...
> 
> You are right, it is the latter of course.

Now I'm completely confused: if blink-cursor timer doesn't drain the
battery, why should we try hard to stop it?  Why isn't it enough to
stop blinking when no Emacs frame has focus?