Re: Running process filters in another thread

[Stefan Monnier <monnier@iro.umontreal.ca>]

> I want to raise this topic regarding the rise of Language servers and
> the performance problems that are related to parsing process output on
> UI thread.

I'm not necessarily surprised that there are performance problems there,
but I'm not actually familiar with them.  Could you point to concrete
examples, bug reports, and things like that?

Ideally, has someone investigated to see exactly where/when the
performance problems show up?

> I am not familiar with Emacs internals and I am not sure whether this
> is doable but I wonder whether providing the option to do the
> parsing(and probably more?)  in a separate thread and then call the
> *filter* function on emacs side in UI thread with elisp data
> structures like lists, hashmaps etc. instead of raw string is feasible
> which would be similar to what is happening in Javascript world.

It shouldn't be too hard to use a separate (OS-level) Emacs *process*
if you want to do the parsing without blocking the normal UI thread.
But it comes with other performance tradeoffs.


        Stefan