Subject: Re: bug#56682: Fix the long lines font locking related slowdowns

From: Eli Zaretskii <[email-masked]>
Date: Tue, 16 Aug 2022 05:33:20 +0300

> Date: Mon, 15 Aug 2022 22:51:16 +0300
> Cc: [email-masked], [email-masked], [email-masked]
> From: Dmitry Gutov <[email-masked]>
> 
> On 15.08.2022 19:58, Eli Zaretskii wrote:
> >> Date: Mon, 15 Aug 2022 19:44:07 +0300
> >> Cc: [email-masked], [email-masked], [email-masked]
> >> From: Dmitry Gutov <[email-masked]>
> >>
> >>>> Here's the profiler output anyway:
> >>>>
> >>>>            1067  85% - command-execute
> >>>>            1067  85%  - call-interactively
> >>>>            1023  82%   - funcall-interactively
> >>>>            1012  81%    - end-of-buffer
> >>>>            1008  81%     - recenter
> >>>>            1008  81%      - jit-lock-function
> >>> When did you last resync from Git?  'recenter' got "optimized"
> >>> yesterday for buffers with long lines.
> >>
> >> Just today.
> >>
> >> In any case, it doesn't look like recenter's problem, since the output
> >> says all (or vast majority) of its time is spent in jit-lock-function.
> > 
> > AFAIU 'recenter' shouldn't at all call jit-lock-function in a buffer
> > with long lines.  Is this "emacs -Q" without any changes from
> > defaults?
> 
> It's a buffer without long lines. Simply a large file.

??? Are we talking about long-line.xml, or are we talking about
some other file?  We did nothing to change the behavior in large files
without long lines.

If you are saying that 'recenter' takes too long in some file, and
therefore delays M-> for too long, it is probably a separate issue, so
please report that as a separate bug, preferably with the file that
causes it.