Emacs 28 with native-compilation / gccemacs

drgibbon · 05-03-2021, 02:07 AM

Just a heads up that native compilation has been merged into the main tree (project here), and I believe it will be the default for Emacs 28. I've not tried it yet, but I hear that it will bring significant performance boosts. This paper claims speed improvements "ranging from 2.3x up to 42x with respect to the equivalent byte-code, measured over a set of small benchmarks". Awesome!

giomat · 05-03-2021, 02:29 AM

Yes it's really fast, i tested it for a while with a local build.
However Im not sure it will be the default build option, as i understood only the compilation flag is made official from experimental. I hope it's not the case though.

cycojesus · 05-03-2021, 04:10 AM

Am I missing something? Because I get

Code:

configure: error: elisp native compiler requested but libgccjit not found.
Please try installing libgccjit or similar package.

2slguevH · 05-03-2021, 06:23 AM

Quote:

Originally Posted by cycojesus

Am I missing something? Because I get

Code:

configure: error: elisp native compiler requested but libgccjit not found.
Please try installing libgccjit or similar package.

For gccjit, build gcc with

Code:

--enable-languages=jit

anon117 · 05-08-2021, 03:59 PM

Praise the light! It is indeed faster(especially noticeable if you use lsp-mode)

usr345 · 05-09-2021, 12:12 AM

Quote:

Originally Posted by Lembrun

Praise the light! It is indeed faster(especially noticeable if you use lsp-mode)

I doubt that, cause LSP mode uses external LSP server and the productivity of the overall system depends upon the speed of the server + communication delays.

Only native Emacs functions will work faster.

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It would be great to have Emacs with native compilation in the new Slackware 15!

anon117 · 05-09-2021, 03:28 AM

Quote:

Originally Posted by usr345

I doubt that, cause LSP mode uses external LSP server and the productivity of the overall system depends upon the speed of the server + communication delays.

Only native Emacs functions will work faster.

---------------------------------------

It would be great to have Emacs with native compilation in the new Slackware 15!

You mean the 200% speedup was a lie ?

https://emacs-lsp.github.io/lsp-mode...ance/#gccemacs.

I attributed the poor performance of lsp to my 10 years old laptop

usr345 · 05-09-2021, 11:49 PM

Quote:

Originally Posted by Lembrun

You mean the 200% speedup was a lie ?

https://emacs-lsp.github.io/lsp-mode...ance/#gccemacs.

I attributed the poor performance of lsp to my 10 years old laptop

200% speedup means that the compiled elisp code runs 200% faster then the previous bytecode. It is only related to native Emacs functions. Here we have the following scheme: (Emacs) <- (Communication line) -> (LSP server).

LSP server won't run faster. And there are still communication delays. There will be a speedup, but not 200%.