Re: Enabling native compilation by default when libgccjit is present

[Dmitry Gutov <dgutov@yandex.ru>]

On 06.12.2021 05:50, Jim Myhrberg wrote:
>>> Especially in larger Ruby RSpec test files (over 400-500 lines), where each keystroke could take somewhere around 100-1000ms to register. Native-comp solved all of that for me, with everything being fast and responsive, even those worst case scenario RSpec files.
>>
>> Was that with lsp-mode enabled?
>>
>> Because otherwise, I routinely edit RSpec files longer than that, with no sluggishness like the one you described.
> 
> I having lsp-mode on or off didn’t really have much of an effect, and I’d had performance issues since before lsp-mode existed. Though the biggest performance killer in long heavily indented rspec files was the highlight-indent-guides package. But even with that turned off, various operations were still pretty slow most of the time, specially inserting a new line which would often take a good 300-500ms on those problematic files.

highlight-indent-guides sounds like it could have an impact indeed, if 
it recomputes indentation for every displayed line on every keypress.

Although reindenting a screen-ful takes about 120ms here, not anything 
close to 1s. And that's without native compilation.

> Admittedly, I’ve not really tried running Emacs without native-comp for nearly a year, and it was nearly 18 months ago I started using native-comp builds. I’m curious now though, so I’ll create a local master build without native comp tomorrow and see how it behaves.

If native-comp helps (which would be natural, given that all indentation 
code is in Lisp), it might be good enough. But it might be worthwhile to 
find the exact bottlenecks and file the corresponding issues. Maybe in 
the aforementioned package. Maybe against ruby-mode. Maybe somewhere else.