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Completion Time Scheduling and the WSRPT Algorithm

  • Bo Xiong
  • Christine Chung
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7422)

Abstract

We consider the online scheduling problem of minimizing the total weighted and unweighted completion time on identical parallel machines with preemptible jobs. We show a new general lower bound of 21/19 ≈ 1.105 on the competitive ratio of any deterministic online algorithm for the unweighted problem and \(\frac{16-\sqrt{14}}{11} \approx 1.114\) for the weighted problem. We then analyze the performance of the natural online algorithm WSRPT (Weighted Shortest Remaining Processing Time). We show that WSRPT is 2-competitive. We also prove that the lower bound on the competitive ratio of WSRPT for this problem is 1.215.

Keywords

Completion Time Parallel Machine Competitive Ratio Online Algorithm Deterministic Algorithm 
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 2012

Authors and Affiliations

  • Bo Xiong
    • 1
  • Christine Chung
    • 1
  1. 1.Department of Computer ScienceConnecticut CollegeNew LondonUSA

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