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In detail, the new heapify reduces the number of comparisons by about 50% when all elements are distinct. However, when all elements are equal, the comparison count can degrade from O(1) to O(log n). I don't have enough domain knowledge of dm-vdo, so I'd like to ask whether it uses heaps with many compare-equal elements. If so, I'll work on fixing the issue. Regards, Kuan-Wei