GNU bug report logs - #56682
Fix the long lines font locking related slowdowns

Previous Next

Full log

Message #1027 received at 56682 <at> debbugs.gnu.org (full text, mbox):

From: Dmitry Gutov <dgutov <at> yandex.ru>
To: Eli Zaretskii <eliz <at> gnu.org>, Stefan Monnier <monnier <at> iro.umontreal.ca>
Cc: 56682 <at> debbugs.gnu.org, gregory <at> heytings.org
Subject: Re: bug#56682: Fix the long lines font locking related slowdowns
Date: Fri, 5 Aug 2022 15:59:57 +0300

On 01.08.2022 14:58, Eli Zaretskii wrote:

> As I wrote elsewhere, I'm okay with extending 'widen' so that it could
> "unlock" the locked narrowing, which could then be used in major modes
> that convince us their performance is adequate (or clearly announce in
> their docs that they don't care about files with long lines ;-).

And to address the idea of "unlocking" the narrowing: I think I have 
demonstrated that the remaining slowdown can be caused purely by the 
length of the buffer and how long 'parse-partial-sexp' takes to parse 
it. That part doesn't have much to do with individual modes.

And of course the more, let's say, *complex* modes like CC Mode will opt 
for unlocking narrowing right away because its font-lock logic has to 
jump around to previously-saved positions in its syntax cache, which 
will inevitably spam errors here and there when those positions are not 
accessible.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.