Subject: bug#13675: Extremely slow redisplay when lines are very long

From: Phil Sainty <[email-masked]>
Date: Sat, 21 Oct 2017 15:03:28 +1300

On 21/10/17 00:57, Phil Sainty wrote:
> FWIW I wrote https://savannah.nongnu.org/projects/so-long which
> tries to avoid performance issues in buffers with unexpectedly
> long lines by automatically changing the major mode and disabling
> various minor modes for that buffer

I wrote a more detailed overview at:
https://lists.gnu.org/archive/html/emacs-devel/2016-07/msg00742.html

That was preparation for adding so-long.el to GNU ELPA -- before I
came to the realisation that the scenarios which affected me had all
been caused by third-party libraries, and that the most notable
issue had already been fixed upstream by the library's author.

At this point I worried that I was severely over-stating the benefits
of my code, as I no longer had a good example of my library improving
things by a significant margin, and in particular could not find a
scenario using only default Emacs libraries.  I think this was the
main reason why I didn't proceed with adding so-long to ELPA at the
time.

I do think it might still be worth adding to ELPA, but a good example
of it being useful would be really helpful.

As such, if anyone is reading this, tries out so-long.el, and finds
that it does indeed help them (with or without configuration), please
drop me a line with some details?

thanks,
-Phil