Re: Speedup of display of long and truncated lines

[Eli Zaretskii]

> Date: Sun, 21 Aug 2022 14:22:15 +0300
> Cc: emacs-devel@gnu.org
> From: Dmitry Gutov <dgutov@yandex.ru>
> 
> > sql-mode
> 
> FWIW, my brief testing seems to show sql-mode's font-lock has similar 
> performance to js-json-mode. Maybe like 1.5x slower in syntax-ppss (due 
> to syntax-propertize-function being present), but that's it.
> 
> Tested with font-lock without narrowing, of course.

I think I'm done with this task now.  I installed today two changes in
the scrolling commands and in the display code that make C-v/M-v
significantly faster when lines are very long and truncated on
display.

So, barring crashes and other bugs, I think this issue can be closed.
But if you find situations where Emacs is unbearably sluggish with
long and truncated lines, please report that as bugs, so that they
could be fixed.