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Comment by idunning | Hacker News Reader

Startup times are not fantastic with packages. This hasn't been a big area of focus yet, but there is a roadmap for getting this down.

Its definitely a typo. Stable release is currently 0.2 (released near end of 2013) and upcoming version is 0.3 (a month or so away).

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Unless julia switches to an ahead of time compilation model, startup times will fundamentally stay slow.

LLVM can be used as a jit, but it's really tuned for ahead of time compilation and while the llvm devs want to support jit, their focus will always favor ahead of time compilation.

There's no need to switch Julia to an AOT model, it suffices to supplement it with one, which is exactly what happens for the Julia standard library on master. It's only a question to extend that capability to packages, which is ongoing work.

Couldn't the language simply cache the bytecode compiled when a package runs, and only reload if the timestamp on the compiled code is older than that on the source? I believe this is what python does with its .pyc files. Then it could go a step further and cache the binary generated by compiling the bytecode to machine code... seems like there's a lot of things that could be done to speed up package loading.

This is basically what I meant. Julia doesn't really have a bytecode. There is a lower, type-inferred form of the AST as well as the llvm IR representation. However, instruction selection itself takes quite a bit of time, so if we're caching the IR, we might as well cache the generated machine code (the challenges are basically the same). As I said, it's work-in-progress (it's not that it's hard or anything, but it's a bit of work do it properly, which isn't done yet).

So it becomes an AOT model with good jit support? Neat! I look forward to seeing how the design crystallizes.

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