Analysis of Run Length Selection

• Question 1: Given P locations in memory, how long a run can we expect replacement selection to produce on average?

• Answer 1: On average we can expect a run length of 2P.

• Question 2: What are the costs of using replacement selection?

• Answer 2: Replacement Selection requires much more seeking in order to form the runs. However, the reduction in the number of seeks required to merge the runs usually more than offsets that extra cost.

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