Hi all! Pretty much the title question. I’d like to try Julia for my Master’s thesis (it’s my first time with it), and I too was annoyed by the initial package loading time, especially if I want to quickly try some code. Googling around, it seems like PackageCompiler’s sysimages are the way to go.…

precompile caches type inferred code, while create_sysimage caches machine code. The difference is that system images remove roughly 100% of loading time, but are not relocatable between machines, while precompile files are relocatable, but only remove some of the startup time.

[image] Oscar_Smith: while precompile files are relocatable Precompile files have roughly the same issues with relocatability as sysimages in the sense that any path that gets stored during precompilation will likely be invalid on another machine.

Thanks to both! @Oscar_Smith would you mind expanding what did you mean here? [image] Oscar_Smith: precompile caches type inferred code When you say “type inferred code”, do you mean the code expanded to reflect the actual types used in your script, like C++ templates do? Or is it something…

kind of. For a basic example, consider the code julia> function fib(x) x < 1 && return 1 return fib(x-1) + fib(x-2) end When a user writes fib(10) the function gets compiled for an Int input type. The first step here is parsing and lowering, which converts the code to julia> @code_lowered…

Your answer is a treasure, thank you! :smiling_face_with_tear: Fun fact: my thesis is going to be on LLVM, so I think I can learn something from Julia’s compiler.

Ooh, yay! We always appreciate having more people in the community with LLVM knowledge.

What's the difference between `PackageCompiler.create_sysimage()` and `Pkg.precompile()`?

New to Julia

tfiers October 9, 2022, 6:12am 8

[edit: posted as standalone question]

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What's the difference between `PackageCompiler.create_sysimage()` and `Pkg.precompile()`?

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