Hi Heikki, > What is the worst case scenario for the loser tree, where the heap is > faster? How big is the difference?
In tuplesort_heap_replace_top(), it has 2 comparisons each level, but it can early return if the parent less than both child. In tuplesort_loser_tree_adjust(), it has 1 comparison each level, but it can't early return. So on specific data, the heap may be better than the loser tree. But I think the possibility is very small. -- Regards, ChangAo Chen
