A Walk with LuaJIT

#1

Post by damir » Tue, Nov 19, 2024, 7:38 AM UTC

A Walk with LuaJIT
polarsignals.com

Re: A Walk with LuaJIT

#2

Post by brancz » Thu, Nov 21, 2024, 9:03 PM UTC

Thanks for submitting! We know HN has a sweet spot for LuaJIT, so we figured it would eventually end up here.

Quick summary: this post dives into the gory details of how we implemented an eBPF based profiler for LuaJIT.

Let us know if you have any questions on this, we’ll keep an eye out on comments!

Re: A Walk with LuaJIT

#3

Post by alberth » Thu, Nov 21, 2024, 9:06 PM UTC

I’m tremendous excited about LuaJIT 3.0 development.

https://github.com/LuaJIT/LuaJIT/issues/1092

Q: does anyone know timeline on the release?

Re: A Walk with LuaJIT

#4

Post by rurban » Thu, Nov 21, 2024, 9:36 PM UTC

alberth wrote: post #3

I’m tremendous excited about LuaJIT 3.0 development. https://github.com/LuaJIT/LuaJIT/issues/1092 Q: does anyone know timeline on the release?

Looks like 10 years to me

Re: A Walk with LuaJIT

#5

Post by neomantra » Thu, Nov 21, 2024, 9:55 PM UTC

brancz wrote: post #2

Thanks for submitting! We know HN has a sweet spot for LuaJIT, so we figured it would eventually end up here. Quick summary: this post dives into the gory details of how we implemented an eBPF based profiler for LuaJIT. Let us know if you have any questions on this, we’ll keep an eye out on comments!

Very deep dive, thank you for sharing it all. So cool it traverses callbacks too.

Re: A Walk with LuaJIT

#6

Post by brancz » Thu, Nov 21, 2024, 9:59 PM UTC

neomantra wrote: post #5

brancz wrote: post #2

Thanks for submitting! We know HN has a sweet spot for LuaJIT, so we figured it would eventually end up here. Quick summary: this post dives into the gory details of how we implemented an eBPF based profiler for LuaJIT. Let us know if you have any questions on this, we’ll keep an eye out on comments!

Very deep dive, thank you for sharing it all. So cool it traverses callbacks too.

Glad you liked it! Yeah, we worked with a customer who really needs this badly and has done some unspeakable things to get by until now.

Re: A Walk with LuaJIT

#7

Post by slekker » Thu, Nov 21, 2024, 10:10 PM UTC

rurban wrote: post #4

alberth wrote: post #3

I’m tremendous excited about LuaJIT 3.0 development. https://github.com/LuaJIT/LuaJIT/issues/1092 Q: does anyone know timeline on the release?

Looks like 10 years to me

Why do you think that?

Re: A Walk with LuaJIT

#8

Post by gnurizen » Thu, Nov 21, 2024, 10:45 PM UTC

I wrote the code and the blog, happy to answer any questions/comments. Very eager to have folks try it out and give feedback! Like is my meme game strong or very strong? J/K

There's some missing bits around FFI and callbacks (i.e. C calling function pointer that is a luajit generated stub back into the interpreter) and curious if anyone actually uses these things in OpenResty workloads. Deploy and enjoy!

Re: A Walk with LuaJIT

#9

Post by [deleted] » Thu, Nov 21, 2024, 10:49 PM UTC

brancz wrote: post #2

Thanks for submitting! We know HN has a sweet spot for LuaJIT, so we figured it would eventually end up here. Quick summary: this post dives into the gory details of how we implemented an eBPF based profiler for LuaJIT. Let us know if you have any questions on this, we’ll keep an eye out on comments!

[deleted]

Re: A Walk with LuaJIT

#10

Post by dkersten » Thu, Nov 21, 2024, 11:01 PM UTC

slekker wrote: post #7

rurban wrote: post #4

Earlier quoted context omitted.

Looks like 10 years to me

Why do you think that?

None of the items listed there have been ticked off in the time since the ticket was opened, not even the “create v3 branch” one. Mike also has had plans for v3 for at least the last decade too.

So, I’m sure it’ll get worked on when he can, and it’ll be great when it’s done, but it doesn’t look like there’s active development on it and it doesn’t look like it will happen any time soon. I hope in wrong, of course, but it just doesn’t seem likely.