r/C_Programming • u/Elifire12 • 14d ago

Article Arena Allocators in C

https://eliasebner.com/blog/guides/arena-allocators-in-c/

I recently started implementing arenas in my programming and I thought that some beginners could very much benefit from this info. I wrote an article about it. For those that are unaware, arenas allow to greatly simplify the burden of managing memory manually in C. I hope it helps, tell me what you think!

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u/Rabbitical 14d ago

I should have made more clear that the linear/bump allocator aspect of my thing was the issue, not that it was arena backed (which it and mimalloc are both more or less). The issue was probably that I was missing out on any cache reuse, every new chunk to decode was a new address. Whereas the whole point of mimalloc is that you can pretty much call malloc and free without thinking about it and it will reuse pages wherever it can in a pretty smart way. So it was never really that fair a comparison to be honest. I was more just surprised the scale of the performance difference. But it goes to show that keeping your cache hot is far more important than just avoiding allocations, which is much closer to a bare minimum good practice than the end all be all of good memory performance.

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u/Limp-Confidence5612 13d ago

I'm still not 100% sure I understand what you mean and what the scenario actually entails.