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Maybe declaring nbits in the allocation API as > NonZero would help - IDK... I just want to make sure we're not > bloating the implementation for unneeded and confusing functionality. I think the current code is pretty much as simple as we can make it for our use-case. Of course we can always tune it and even update the API if we find out it doesn't work as well as we thought, or that allowing zero-sized pools create issues. But if we forbid them preemptively we would actually be adding more complexity, which makes me think the current approach looks right.