this post was submitted on 22 Aug 2025
12 points (83.3% liked)

Emacs

2718 readers
2 users here now

Our infinitely powerful editor.

founded 6 years ago
MODERATORS
 

I "live in Emacs", like most of us (atleast at work). It has been getting slower release on release, async support doesn't seem to have been picked up by most packages and native-comp has made it more brittle.

Over this time, we moved from running the OS on hardware to running in VMs, so fractional slowdown was expected. But what I have is a few X slower Emacs. I had never seen Emacs take a minute to indent a few thousand lines, for example. Maybe some modes have slower code.

you are viewing a single comment's thread
view the rest of the comments
[–] monnier@lemmy.ca 3 points 3 months ago (1 children)

Time to reindent lines is something that tends to increase, as indentation quality is improved over the years (and as the need increases to support ever more syntactic features of the indented language).
But it really depends more on the text being indented and the mode in use than on the version of Emacs, IME.

[–] tetrislife@leminal.space 2 points 3 months ago (1 children)

Thanks. True, verilog-mode is maybe 6 times slower than c++-mode. I should add some treesitter grammars and try c++-ts-mode etc.

File opening being slow must be a different aspect.

[–] tetrislife@leminal.space 2 points 1 month ago

BTW, I liked the idea on emacs-devel about PGO/FDO experiments. And, with a short PGO Emacs session and compiling Emacs with that profile, I see almost all the responsiveness issues disappear. What is left are slow indent-region and slow file opening, which seem unrelated to UI responsiveness.

Are there automated UI test runners? Just a matter of recording macros, or even writing out elisp, I guess. Having targeted tests and using them for PGO/FDO to do Emacs releases seems useful.