What do @inbounds and @inline do?

[djsegal]

These two macros – @inbounds and @inline – get thrown around a lot when performance comes up.

• What exactly do they do?
• When should you use them?
• When should you not use them?

Also, are there other useful performance macros that people should be aware of?

// asking b/c I’m trying to sprinkle some speedups throughout a codebase

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edit: this is the explain-like-im-five version of:

Performance Tips · The Julia Language

[bennedich]

Just making sure you saw the section on performance annotations? I was going to write something, but I don’t think I can explain it any better than this:

https://docs.julialang.org/en/latest/manual/performance-tips/#man-performance-annotations-1

There’s also this similar topic; a bit old, but still relevant I think:

Questions on a number of code acceleration techniques

I have been trying to step up my game in Julia by thinking more parallel and speed to make the fastest version of my code, and I find myself faced with a number of not-so-thoroughly-documented options so I have a few questions: I understand that @inbounds drops checking the bounds when accessing an array element, but why would not using that be ever a use case? I assume every functioning piece of code should not have any array cross its bounds. So after testing my code, and making sure no out…

[kristoffer.carlsson]

The performance documentation is quite extensive and written to be useful for normal (non-expert) julia users. It would be easier to help you if you pointed out specifically what parts you had troubles understanding.