JEP 544: Ahead-of-Time Code Compilation

(openjdk.org)

23 points | by Skinney 2 hours ago ago

10 comments

  • SillyUsername an hour ago

    So we've gone full circle again?

    I suppose write once run anywhere is no longer a goal either.

    "It is not a goal to support all CPU architectures currently supported by HotSpot."

    This pretty much validates the point of view that VM design is now baggage, as a sandbox it has been flawed, for performance it's been prohibitive, and cross platform portability by virtue of being virtual, was just a convenient byproduct.

    AI now handles the portability, sandbox security hasn't changed (cf. docker still has sandbox problems, LLMs have sandbox problems, it's always an ongoing concern) and that just leaves Java, as always, chasing performance.

    • nirvdrum an hour ago

      The very next sentence after the one you posted is "We expect normal porting activities to eventually add support for all major architectures." Goals and non-goals inform the scope of the proposal. Given this is effectively an "add-on", I don't think it's unreasonable to prioritize the most popular platforms. Others will continue to execute Java perfectly fine in JVM mode.

  • cyberax an hour ago

    Excelsior JET did that 25 years ago: https://en.wikipedia.org/wiki/Excelsior_JET

    It's a shame that Sun/Oracle never partnered with them to bring native apps. This could have saved Java on the desktop.

    • wahern 29 minutes ago

      Don't forget GCJ. It wasn't removed from GCC until about 2016, a nearly 20-year long run, though interest had waned many years prior.

      I don't remember if GCJ supported loading and running code dynamically with a built-in JIT or interpreter. I think it was just pure AOT, which caused some compatibility headaches.

      • java-man 14 minutes ago

        GCJ was great - I wrote a handset UI entirely in java for a startup in the early 2000's, basically android before android existed, using GCJ. I remember their native interface was somewhat more convenient to use than JNI.

        I wish we had GCJ resurrected, now that the java libraries are GPL'd.

    • patwolf an hour ago

      IBM's J9 had AOT for a long time too. I wonder how JEP 544 compares.

  • java-man an hour ago

    I hope at some point we'll get AOT-only mode (or compile to native) and maybe even cross-compilation.

    • nirvdrum an hour ago

      If you haven't checked it out yet, GraalVM's Native Image [1] already let's do AOT compilation suitable for distribution. You have to do some configuration to deal with reflection and dynamic class loading since there's no JVM in the produced build, but it comes with tooling to simplify that. And that restriction is being addressed by Project Crema [2].

      [1] -- https://www.graalvm.org/latest/reference-manual/native-image... [2] -- https://github.com/oracle/graal/issues/11327

    • exabrial 38 minutes ago

      progress, not perfection! Java is on fire right now with new stuff landing. We'll get there!

    • invalidname an hour ago

      We have that in Codename One, yes it's not really "Java" but it compiles bytecode AOT and cross compiles to some of the platforms.