Weak Adversaries for the k-Server Problem
نویسنده
چکیده
We study the -server problem when the off-line algorithm has fewer than servers. We give two upper bounds of the cost WFA of the Work Function Algorithm. The first upper bound is OPT OPT , where OPT denotes the optimal cost to service by servers. The second upper bound is OPT OPT for . Both bounds imply that the Work Function Algorithm is -competitive. Perhaps more important is our technique which seems promising for settling the -server conjecture. The proofs are simple and intuitive and they do not involve potential functions. We also apply the technique to give a simple condition for the Work Function Algorithm to be -competitive; this condition results in a new proof that the -server conjecture holds for "!# .
منابع مشابه
On-Line Algorithms and the k-Server Conjecture
The Work Function Algorithm, a natural algorithm for the k-server problem, is shown to have competitive ratio at most 2k− 1 for all metric spaces. It is also shown that the k-server conjecture, which states that there is an on-line algorithm for the k-server problem with competitive ratio k, holds for all metric spaces with k + 2 points. Furthermore, two refinements of competitive analysis are ...
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