Re: read-process-output-max

[Eli Zaretskii]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Cc: raman@google.com,  cpitclaudel@gmail.com,  emacs-devel@gnu.org
> Date: Wed, 31 Mar 2021 19:05:59 -0400
> 
> > Another potential issue, in programs that display the arriving stuff
> > as it is received, is that showing the text in small chunks is
> > generally better (UX-wise) than blasting a 1MB chunk of text to the
> > screen in one go.
> 
> If 64kB already arrived, will part of the result really reach the eyes
> of the user faster if we process them as 16 chunks of 4kB or do we skip
> redisplay between the chunks (just like we skip redisplay when there
> are pending input events)?

The result of inserting large chunks of text into a buffer that's
displayed will be a continuously scrolling window, whereas if we do
that in smaller chunks, the text will be static for long enough to
allow at least some of it being read (at least with the default
scrolling behavior).  I think the latter is less annoying, at least in
some use cases (think the likes of "M-x compile" and "M-x grep").

> [ BTW, I think a value >=32kB would be desirable since it avoids
>   breaking UDP datagrams.  ]

If we want to do that, we should bump the alloca threshold in
SAFE_ALLOCA higher, it is currently set at 16KB.