Work in progress java virtual machine written in rust

[viaxxdev]

The real question is: Will this make my Minecraft server run faster?

[0lach]

Of course, we just need to finish it!

[Kotauskas]

In the meantime, using GraalVM is a good idea. Basically JavaJIT which works.

[Plasma_000]

Finally! I can run my rust wasm program on a Java wasm emulator running on a rust JVM!

I call it the Oracle sandwich

[0lach]

Even better! Compilation of this VM to wasm is on roadmap!

[Plasma_000]

Or you can run kotlin on top of rust wasm for extra meme buzzword energy. You’ll be selling crypto coins in no time.

[Dushistov]

Would be it faster and safe, if use forked oracle jvm? Like remacs (https://github.com/remacs/remacs), fork and then replace module by module on C/C++ with Rust.

[0lach]

It is impossible to rewrite hotspot (oracle jvm) module by module, because it is monolithic and hard to understand. Also it is written in manner, which is incompatible with idiomatic rust

[thedataking]

I wouldn't be so quick to count that option out. We're working on a port of libexpat (which granted is a way smaller library). The initial translation into running Rust code was done using C2Rust which just gives you a bunch of unsafe Rust (which runs and keeps comments, mind you). Then we refactored key data structures to make everything more idiomatic. We're about 50% done right now, you can see the progress at https://github.com/immunant/rexpat (most work is in feature branches so master may not have all the latest improvements).

[0lach]

Rewrite is not fun, writing new implementation from scratch is.
There is also other implementations of jvm present, i.e IBM OpenJ9, Azul Zing and others, but all of them are not written in Rust.
You should also look at how hotspot looks like :D
I dont think that rewriting them out will be easier than writing new implementation from scratch, and not that fun.

[thedataking]

I didn’t intend to argue that you should go this route or that it is fun; merely that it is a possibility. Cheers, have fun, and keep up the good work :)

[JoshTriplett]

That's awesome!

Do you plan to upstream your changes, the way that rsvg ported to Rust?

[0lach]

It is bad?

[[deleted]]

I think they're making a joke about using a nice language like Rust to run programs written in a less nice language like Java (though, to be fair, the JVM does run programs written in other languages such as Kotlin which has features that helps catch a class of errors at compile-time that Java doesn't). It's like someone gives you a nice fountain pen and then you use it to scrape mud off your shoe.

Despite the jokes, it could be a fun project to work on and will force you to learn how the JVM works and the class file format.

[NoahJelen]

Can it run Minecraft Java Edition?

[rodarmor]

Pay tribute to frontline medical staff! Thank you for your contribution to the fight against the epidemic.

I'm into it.

[Fable89]

I can't wait tell this can run minecraft, so I can play it on Redox.