Re: bug-reference-prog-mode slows down CC Mode's scrolling by ~7%

[Eli Zaretskii]

> Date: Sat, 4 Sep 2021 15:43:40 +0000
> Cc: monnier@iro.umontreal.ca, emacs-devel@gnu.org
> From: Alan Mackenzie <acm@muc.de>
> 
> > > Indeed.  With jit-lock-chunk-size at 2000, time-scroll on xdisp.c takes:
> 
> > > (current code): 16.4s
> > > (new proposed code): 16.1s
> 
> > > ..  This speed up may well be particular to CC Mode.
> 
> > > Let's try jit-lock-chunk-size at 8000:
> 
> > > (current code): 15.1s
> > > (new proposed code): 15.1s
> 
> > > ..  So, yes, it would seem a larger chunk size is advantageous for CC
> > > Mode.
> 
> > How large (in lines and columns) is your window?  The above numbers
> > are only meaningful with the window size.
> 
> I'm running in a window with 65 lines and 118 columns.

That's significantly larger than the default size.  Can you repeat
your experiments with the default size set by "emacs -Q", for
reference?

Thanks.