Re: Elisp LSP Server

[Po Lu]

Eli Zaretskii <eliz@gnu.org> writes:

> The main benefit, AFAIU, is to use the system's execution units more
> efficiently by off-loading some of the CPU-intensive work to another
> Emacs process.

On the other hand, this doesn't require making the Emacs instance act as
a language server, which will also come with the benefit of not having
to use a mechanism as bloated as JSON RPC for communication.

Implementing an entire Language Server when the goal is to offload work
onto another execution unit seems overkill to me.

> I'm surprised.  How large are memory footprints of "other LSP language
> servers", and how large do you envision the footprint of Emacs-based
> server to be?  Emacs has ceased to be THE memory hog long ago, it's
> actually quite modest in its memory requirements nowadays.  So I don't
> see why this particular job would require Emacs to become such a
> memory-hungry application.

FWIW, CCLS, a popular language server for C/C++ code can easily take
many gigabytes of RAM when working on relatively large C++ codebases.

I don't remember exactly how much CCLS took on the Emacs codebase
(everything in lib, lib-src, and src), but it was somewhere around 600
megabytes.