Preemptive Online Scheduling: Optimal Algorithms for All Speeds

  • Tomáš Ebenlendr
  • Wojciech Jawor
  • Jiří Sgall
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4168)


Our main result is an optimal online algorithm for preemptive scheduling on uniformly related machines with the objective to minimize makespan. The algorithm is deterministic, yet it is optimal even among all randomized algorithms. In addition, it is optimal for any fixed combination of speeds of the machines, and thus our results subsume all the previous work on various special cases. Together with a new lower bound it follows that the overall competitive ratio of this optimal algorithm is between 2.054 and e ≈2.718.


Virtual Machine Competitive Ratio Online Algorithm Identical Machine Online Schedule 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Tomáš Ebenlendr
    • 1
  • Wojciech Jawor
    • 2
  • Jiří Sgall
    • 1
  1. 1.Mathematical InstitutePraha 1Czech Republic
  2. 2.Department of Computer ScienceUniversity of CaliforniaRiversideUSA

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