I spent a while rewriting a tiny bit of some useful Ruby in Rust and integrating it via Wasmer, and I definitely think my time expenditure is better classified as "fun thing to do" than "magic fix".
My goal was to determine: how will I use Wasm as a Rubyist? Spoiler: I did not intend to use Rust, but embedding Ruby in a Wasm and running it from within Ruby proved to be a fool's exercise. I have a feeling that some of the claims I made in this talk about there being "no theoretical benefit" to running Ruby in Wasm in Ruby will quickly be proven incorrect. But I'm not expecting it to be faster.
If it's ever faster, that will be filed under "surprising results"
Michael Yuan who obviously knows a lot more about Wasm than I do addressed this in his talk as well, but not from the perspective of a JIT necessarily, although I guess you could consider local machine compile target optimization on the target machine at runtime as a type of "just in time optimization" it's not really (it's just the regular ahead-of-time type of optimization, but not fumbled and the majority of benefits immediately getting lost in such a way as it usually is...)
The spoiler from that talk (for me anyway) was finding out that you do see surprising results sometimes, and sometimes it's due to a pathological case that (a) happens all the time, and (b) does not have a readily obvious solution in the form the problem regularly takes. Like linux distros shipping generic binaries "target-optimized" for the lowest common denominator on any given particular architecture dist target, because the binaries they ship obviously have to run anywhere.
(Recap of the conversation we had off-stage after the Q&A ended: We don't know when we say "x86-64" what modern opcode targets that means we really have available, so we have to ship a binary with only the oldest opcodes that are guaranteed to be available on any similar chip that we intend to support. Web Assembly uses a compiler on the target machine, cranelift, to translate from a platform independent binary to a platform-specific one. Running the compiler takes a while, but we can do it ahead of time. Will we come out ahead in the end?)
All of this stuff is certainly very fun to reason about :D
https://ossna2023.sched.com/event/1K55z/exotic-runtime-targe...
https://www.youtube.com/watch?v=EsAuJmHYWgI
My goal was to determine: how will I use Wasm as a Rubyist? Spoiler: I did not intend to use Rust, but embedding Ruby in a Wasm and running it from within Ruby proved to be a fool's exercise. I have a feeling that some of the claims I made in this talk about there being "no theoretical benefit" to running Ruby in Wasm in Ruby will quickly be proven incorrect. But I'm not expecting it to be faster.
If it's ever faster, that will be filed under "surprising results"
Michael Yuan who obviously knows a lot more about Wasm than I do addressed this in his talk as well, but not from the perspective of a JIT necessarily, although I guess you could consider local machine compile target optimization on the target machine at runtime as a type of "just in time optimization" it's not really (it's just the regular ahead-of-time type of optimization, but not fumbled and the majority of benefits immediately getting lost in such a way as it usually is...)
https://www.youtube.com/watch?v=kOvoBEg4-N4
The spoiler from that talk (for me anyway) was finding out that you do see surprising results sometimes, and sometimes it's due to a pathological case that (a) happens all the time, and (b) does not have a readily obvious solution in the form the problem regularly takes. Like linux distros shipping generic binaries "target-optimized" for the lowest common denominator on any given particular architecture dist target, because the binaries they ship obviously have to run anywhere.
(Recap of the conversation we had off-stage after the Q&A ended: We don't know when we say "x86-64" what modern opcode targets that means we really have available, so we have to ship a binary with only the oldest opcodes that are guaranteed to be available on any similar chip that we intend to support. Web Assembly uses a compiler on the target machine, cranelift, to translate from a platform independent binary to a platform-specific one. Running the compiler takes a while, but we can do it ahead of time. Will we come out ahead in the end?)
All of this stuff is certainly very fun to reason about :D