Journal of Scheduling

, Volume 14, Issue 1, pp 89–101 | Cite as

Competitive ratio of List Scheduling on uniform machines and randomized heuristics

  • Antoine Musitelli
  • Jean-Marc Nicoletti


We study online scheduling on m uniform machines, where m−1 of them have a reference speed 1 and the last one a speed s with 0≤s≤1. The competitive ratio of the well-known List Scheduling (LS) algorithm is determined. For some values of s and m=3, LS is proven to be the best deterministic algorithm. We describe a randomized heuristic for m machines. Finally, for the case m=3, we develop and analyze the competitive ratio of a randomized algorithm which outperforms LS for any s.


Analysis of algorithms Online algorithms Competitive ratio Randomized scheduling 


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Dipartimento di Matematica pura ed applicataUniversità degli Studi di PadovaPadovaItaly
  2. 2.ROSO/IMAEPFLLausanneSwitzerland

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