Scheduling Unrelated Parallel Machines Computational Results

  • Burkhard Monien
  • Andreas Woclaw
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4007)


Scheduling n independent jobs on m unrelated parallel machines without preemption belongs to the most difficult scheduling problems. Here, processing job i on machine j takes time p ij , and the total time used by a machine is the sum of the processing times for the jobs assigned to it. The objective is to minimize makespan. In this paper we present an experimental study on the Unsplittable-Truemper algorithm. This purely combinatorial approach computes 2-approximate solutions in the best worst-case running time known so far. The goal of our simulations was to prove its efficiency in practice. We compare our technique with algorithms and heuristics used in practice, especially with those based on the two-step approach. The experiments show that for large and difficult instances the Unsplittable-Truemper algorithm has a clear advantage over methods based on linear programming. Moreover, it requires much less operational memory, and thus is more effective and easier to handle.


Schedule Problem Bipartite Graph Column Generation Master Problem Linear Programming Relaxation 
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

  • Burkhard Monien
    • 1
  • Andreas Woclaw
    • 1
  1. 1.Faculty of Computer Science, Electrical Engineering and MathematicsUniversity of PaderbornPaderbornGermany

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