Competitive analysis of randomized paging algorithms
In this paper we use competitive analysis to study the performance of randomized on-line paging algorithms. We present two results: we first show that the competitive ratio of the marking algorithm is exactly 2Hk−1. Previously, it was known to be between H k and 2H k . Then we provide a new, H k -competitive algorithm for paging. Our algorithm, as well as its analysis, is simpler than the known algorithm by McGeoch and Sleator. Another advantage of our algorithm is thatit can be implemented with complexity bounds independent of the number of past requests: O(k2 log k) memory and O(k2) time per request.
KeywordsWork Function Competitive Ratio Online Algorithm Optimal Cost Competitive Algorithm
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