Tightness Results for Malleable Task Scheduling Algorithms

  • Ulrich M. Schwarz
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4967)


Malleable tasks are a way of modelling jobs that can be parallelized to get a (usually sublinear) speedup. The best currently known approximation algorithms for scheduling malleable tasks with precedence constraints are a) 2.62-approximation for certain classes of precedence constraints such as series-parallel graphs [1], and b) 4.72-approximation for general graphs via linear programming [2]. We show that these rates are tight, i.e. there exist instances that achieve the upper bounds.


Execution Time Approximation Algorithm Critical Path Precedence Constraint Fractional Solution 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Ulrich M. Schwarz
    • 1
  1. 1.Institut für InformatikChristian-Albrechts-Universität zu KielKielGermany

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