ruby VS yjit

To create a new Rails app, you should have Ruby and Rails installed on your machine. You can find how to install Ruby on your local machine using the Ruby docs. You can install Rails by running the following command:

Ruby testing with RSpec

Not parent poster and do not have production YJIT experience. =)

My guess is that you would monitor `RubyVM::YJIT.runtime_stats[:code_region_size]` and/or `RubyVM::YJIT.runtime_stats[:code_gc_count]` so that you can get a feel for a reasonable value for your application, as well as know whether or not the "code GC" is running frequently.

https://github.com/ruby/ruby/blob/master/doc/yjit/yjit.md#pe...

Link to the commit

Part of the major userbase pull in GitHub revolves around hosting a considerable number of popular projects including Angular, React, Kubernetes, cpython, Ruby, tensorflow, and well even the software that powers this site Forem.

Hold option and click on the “collapse file” button in the Files view of a commit or pull request, and it will collapse all the files.

Select text in a comment, issue, or pull request description and press r—the selected text (including markdown formatting) will get pre-populated as a markdown block quote reply in the next comment box.

Add .patch or .diff to any pull request URL if you want to see a plain-text diff of the pull request (e.g. maybe you want to quickly `curl ... | git apply -` an unmerged pull request into a local copy of the repo without trying to add and fetch the git remote that the pull request is from).

There are lots of keyboard shortcuts. For example, / to jump to the file finder.

Not so much a secret but more like a hiding in plain sight: when looking at a commit GitHub will show you the earliest and latest tag (i.e. release) that includes the commit. For example, this commit[1] first appeared in v3_2_0_preview3.

[1]: https://github.com/ruby/ruby/commit/892f350a7db4d2cc99c5061d...

The title is misleading, just like other commenters mentioned. Just check how much indirection "rb_iv_get()" has to make (at the end, it will call [1], which isn't "a light" call). Now, check generated JIT code (in a blog post) for the same action where JIT knows how to shave off unnecessary indirection.

We are comparing apples and oranges here.

[1] https://github.com/ruby/ruby/blob/b635a66e957e4dd3fed83ef1d7...

I'm not sure why, but all the source values are listed here: https://github.com/ruby/ruby/blob/1cc700907d3ad3368272488a6f...

Maybe someone knowledgeable in the underpinnings of Ruby will explain why "class variable" was not hyphenated.

Ruby 3.2.0 is here and it offers some nice additions to the language. One of the most exciting new things is the addition of a compiler, YJIT. YJIT was created by the folks from Shopify and has been producion tested for a while, so it is safe to use in your environment. Some benchmarks show the difference in speed compared to Ruby without YJIT. I'll put some links if you want to know more: https://speed.yjit.org/ https://www.solnic.dev/p/benchmarking-ruby-32-with-yjit

> I’m curious how the impact affects development, deployment, etc.

YJIT is pretty much transparent in production, if not it's likely a bug.

When we tried MJIT in production to compare it against YJIT, it causes lots of request timeouts on deploy, because the JIT warmup would take 10 to 20 minutes and it's much slower during that phase.

But YJIT warms ups extremely fast and with a much lower overhead, it's seemless on deploy.

The only thing you may need to tweak is `--yjit-exec-mem-size`, it defaults to `--yjit-exec-mem-size=256` (MB) which is not quite enough for larger apps.

As for development, it would work, but with code reloading enabled, you'd likely exhaust the executable memory allocation pretty fast, because for now YJIT doesn't GC generated code [0]. It will come soon, hopefully before the 3.1.0 release, but that's one of the reason why it's not enabled by default.

[0] https://github.com/Shopify/yjit/issues/87

Just want to temper expectations because YJIT is still new. But if you run into crashes or bugs, please open an issue with as much detail as you can: https://github.com/Shopify/yjit

You raised a point that the compiler only does a subset. That's actually what I would expect from a new project. I don't expect a full implementation to start. It takes time for a compiler to be mature enough to be general purpose. Here is another Ruby compiler in its infancy: https://github.com/Shopify/yjit.

We already collaborate extensively with GitHub around Rails and Ruby. Our respective Ruby and Rails infra teams hold regular meetings, and they already contributed substantial patches to YJIT, e.g. https://github.com/Shopify/yjit/pulls/jhawthorn. Also things like https://bugs.ruby-lang.org/issues/17763 are a collaboration.

Yes. I put some suggestions here. I realize that not all of them are practical, but refactoring specific hot methods could make a difference.