perf: cache BaseVec len in Cell<u64> to avoid stable memory reads#415
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perf: cache BaseVec len in Cell<u64> to avoid stable memory reads#415sasa-tomic wants to merge 1 commit intomainfrom
sasa-tomic wants to merge 1 commit intomainfrom
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BaseVec::len() previously read from stable memory on every call. MinHeap calls len() O(log n) times per push/pop via sift_up/sift_down bounds checks, making this a significant overhead. Cache the length in a Cell<u64> and keep it in sync with the persisted value.
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Summary
BaseVec::len()in aCell<u64>instead of reading from stable memory on every callMinHeapcallslen()O(log n) times per push/pop (via bounds checks insift_up/sift_down), making this a significant overhead — eliminates ~13-26 stable memory reads per MinHeap operation on heaps of 10K elementsCell<u64>is necessary because all BaseVec data methods use&self(interior mutability viaMemorytrait)