Online Load Balancing Made Simple: Greedy Strikes Back

  • Pilu Crescenzi
  • Giorgio Gambosi
  • Gaia Nicosia
  • Paolo Penna
  • Walter Unger
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2719)


We provide a new simpler approach to the on-line load balancing problem in the case of restricted assignment of temporary weighted tasks. The approach is very general and allows to derive online distributed algorithms whose competitive ratio is characterized by some combinatorial properties of the underlying graph representing the problem.

The effectiveness of our approach is shown by the hierarchical server model introduced by Bar-Noy et al ’99. In this case, our method yields simpler and distributed algorithms whose competitive ratio is at least as good as the existing ones. Moreover, the resulting algorithms and their analysis turn out to be simpler. Finally, in all cases the algorithms are optimal up to a constant factor.

Some of our results are obtained via a combinatorial characterization of those graphs for which our technique yields O(\( \sqrt n \))-competitive algorithms.


Bipartite Graph Greedy Algorithm Competitive Ratio Task Type Competitive 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 2003

Authors and Affiliations

  • Pilu Crescenzi
    • 1
  • Giorgio Gambosi
    • 2
  • Gaia Nicosia
    • 3
  • Paolo Penna
    • 4
  • Walter Unger
    • 5
  1. 1.Dipartimento di Sistemi ed InformaticaUniversità di FirenzeFirenzeItaly
  2. 2.Dipartimento di MatematicaUniversità di Roma “Tor Vergata”RomaItaly
  3. 3.Dipartimento di Informatica e AutomazioneUniversità degli studi “Roma Tre”RomaItaly
  4. 4.Dipartimento di Informatica ed Applicazioni “R.M. Capocelli”Università di SalernoBaronissi (SA)Italy
  5. 5.RWTH AachenAachenGermany

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