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The Weighted 2-Server Problem

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STACS 2000 (STACS 2000)

Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 1770))

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Abstract

We consider a generalized 2-server problem in which servers have different costs. We prove that, in uniform spaces, a version of the Work Function Algorithm is 5-competitive, and that no better ratio is possible. We also give a 5-competitive randomized, memoryless algorithm for uniform spaces, and a matching lower bound. For arbitrary metric spaces, we prove that no memoryless randomized algorithm has a constant competitive ratio. We study a subproblem in which a request specifies two points to be covered by the servers, and the algorithm decides which server to move to which point; we give a 9-competitive deterministic algorithm for any metric space (no better ratio is possible).

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Author information

Authors and Affiliations

  1. Department of Computer Science, University of California, Riverside, CA, 92521

    Marek Chrobak

  2. Mathematical Inst., AS CR, Žitná 25, CZ-11567, Praha 1, Czech Republic

    Jiří Sgall

  3. Dept. of Applied Mathematics, Faculty of Mathematics and Physics, Charles Univ., Praha

    Jiří Sgall

Authors
  1. Marek Chrobak
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  2. Jiří Sgall
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Editor information

Editors and Affiliations

  1. Faculty of Computer Science, Dept. of Theoretical Computer Science, Universität Dresden, 01062, Dresden, Germany

    Horst Reichel

  2. Université de Lille, LIFL - UPRESA 8022, CNRS, Bât. M3 - UFR IEEA, 59655, Villeneuve d’ASCQ Cedex, France

    Sophie Tison

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© 2000 Springer-Verlag Berlin Heidelberg

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Chrobak, M., Sgall, J. (2000). The Weighted 2-Server Problem. In: Reichel, H., Tison, S. (eds) STACS 2000. STACS 2000. Lecture Notes in Computer Science, vol 1770. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-46541-3_49

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  • DOI: https://doi.org/10.1007/3-540-46541-3_49

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-67141-1

  • Online ISBN: 978-3-540-46541-6

  • eBook Packages: Springer Book Archive

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