Re: Default of jit-lock-stealth-time

[David Kastrup <dak@gnu.org>]

Eli Zaretskii <eliz@gnu.org> writes:

>> Cc: rms@gnu.org,  emacs-devel@gnu.org
>> From: David Kastrup <dak@gnu.org>
>> Date: Sun, 04 Mar 2007 14:29:48 +0100
>> 
>> I can send you the file in question
>
> If that's the standard texbook.tex from CTAN, I have it.  FWIW, I
> don't see any special problem with it in "emacs -Q".  JIT stealth
> still takes 1-3% of CPU on a 3GHz box, when this file is the only one
> loaded in a session.
>
>> but you'll probably need font-latex and possible other AUCTeX
>> components for reproducing the problem.
>
> Are there other files which exhibit similar problems?  Or did we just
> change the defaults because of some singular case, which on top of
> that needs unbundled packages to raise its ugly head?

I get similar effects with other files (not just TeX files, C mode has
shown similar problems in some iterations), and if you had followed
the discussion closely, you'd have realized that several other
developers have disabled jit-lock-stealth-time previously for their
own problems using it.

I apologize for providing an actual example if it causes such a
reaction.

In case you have forgotten: I have repeatedly stated that there might
very well be problems with some font lock patterns in some modes.  The
problem with stealth fontification is that it makes those problems
non-debuggable, non-deterministic and spreads their bad effects across
all buffers and modes, without the user being able to pinpoint them
any more.

With the current settings, such problems, if they exist, will exhibit
themselves when paging through the affected areas.  People will be
able to report them.  Currently, we instead let Emacs drain the
batteries without a possibility to pinpoint when and why that is
happening.

And again: it is not just me and not just a single file and setup:
_several_ other developers have, after my report, stated that they had
long ago disabled stealth fontification for similar reasons.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum