Abstract
We consider a generalized 2-server problem on the uniform space in which servers have different costs. Previous work focused on the case where the ratio between these costs was very large. We give results for varying ratios. For ratios below 2.2, we present an optimal algorithm which is trackless. We present a general lower bound for trackless algorithms depending on the cost ratio, proving that our algorithm is the optimal trackless algorithm up to a constant factor for any cost ratio. The results are extended for the case where we have two sets of servers with different costs.
Research supported in part by the Israel Science Foundation (grant no. 250/01).
Research supported by Future and Emerging Technologies programme of the EU under contract number IST-1999-14186 (ALCOM-FT) and by the Hungarian National Foundation for Scientific Research, Grant TO30074.
Work supported by the Deutsche Forschungsgemeinschaft, Project AL 464/3-1, and by the European Community, Projects APPOL and APPOL II.
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References
A. Aggarwal, B. Alpern, A. K. Chandra, and M. Snir. A model for hierarchical memory. In Proceedings of the 19th ACM Symposium on the Theory of Computing, pages 305–313. ACM, 1987.
W. W. Bein, R. Fleischer, L. L. Larmore, Limited bookmark randomized online algorithms for the paging problem, Information Processing letters, 76: 155–162, 2000.
W. W. Bein, L. L. Larmore, Trackless online algorithms for the server problem, Information Processing letters, 74 no 1–2: 73–79, 2000.
L. Belady, A study of replacement algorithms for virtual storage computers, IBM Systems Journal 5: 78–101, 1966
Marek Chrobak and John Noga. Competitive algorithms for multilevel caching and relaxed list update (extended abstract). In Proceedings of the Ninth ACM-SIAM Symp. on Discrete Algorithms, pages 87–96. ACM/SIAM, 1998.
M. Chrobak and J. Noga. LRU is better than FIFO. Algorithmica, 23:180–185, 1999.
M. Chrobak, J. Sgall, The weighted 2-server Problem, in Proc. of STACS 2000, LNCS 1770, Springer-Verlag Berlin, 593–604, 2000.
A. Fiat, M. Ricklin, Competitive algorithms for the weighted server problem, Theoretical Computer Science, 130: 85–99, 1994.
A. Karlin, M. Manasse, L. Rudolph, D. Sleator, Competitive snoopy caching, Algorithmica, 3(1): 79–119, 1988.
M. Manasse, L. A. McGeoch, and D. Sleator. Competitive algorithms for server problems. Journal of Algorithms, 11:208–230, 1990.
L. Newberg, The K-server problem with distinguishable servers, Master’s Thesis, Univ. of California at Berkeley, 1991.
D. Sleator, R. E. Tarjan, Amortized efficiency of list update and paging rules, Communications of the ACM, 28:202–208, 1985.
N. Young, Online file caching, Proc. 9th Annual ACM-SIAM Symp. on Discrete Algorithms, 82–86, 1998 (to appear in Algorithmica)
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Epstein, L., Imreh, C., van Stee, R. (2002). More on Weighted Servers or Fifo is Better than Lru . In: Diks, K., Rytter, W. (eds) Mathematical Foundations of Computer Science 2002. MFCS 2002. Lecture Notes in Computer Science, vol 2420. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-45687-2_21
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DOI: https://doi.org/10.1007/3-540-45687-2_21
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