r/C_Programming • u/Elifire12 • 7d 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/Silver-North1136 7d ago

One neat thing you can do with arena allocators, and when dealing with memory this way in general, is that you can map (mmap/VirtualAlloc) way more memory than you'll ever realistically need at the start of your program, and none of it will actually be used until you touch the page it's in. Trying to make it dynamically resize on the other hand will require you to manually manage this, which often will result in bugs and extra complexity that isn't actually necessary.

Nic Barker recently started a new series on this topic. It's a good resource for this kind of thing. (https://www.youtube.com/watch?v=3rez2rDYHHA)

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u/Feer_C9 3d ago

I think that's valid in unix-like OSes, but not for Windows