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A comment on Futurelock: A subtle risk in async Rust. Parent comment

Re:Futurelock: A subtle risk in async Rust by fpoling on Saturday November 01, 2025 @02:03AM (#45779568)
Even with the stack the memory can fragment. Just consider one created 10 features on the stack and the last completed last. Then memory for the first 9 will not be released until the last completes.

This problem does not happen with a custom allocator where things to allocate are of roughly the same size and allocator uses same-sized cells to allocate.

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Re:Futurelock: A subtle risk in async Rust by jacquesm on Saturday November 01, 2025 @02:53AM (#45779721)
Indeed, arena allocators are quite fast and allow you to really lock down the amount of memory that is in use for a particular kind of data. My own approach in the embedded world has always been to simply pre-allocate all of my data structures. If it boots it will run. Dynamic allocation of any kind is always going to have edge cases that will cause run-time issues. Much better to know that you have a deterministic system.
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