Towards Parallel Non Serial Dynamic Programming for Solving Hard Weighted CSP

  • David Allouche
  • Simon de Givry
  • Thomas Schiex
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6308)


We introduce a parallelized version of tree-decomposition based dynamic programming for solving difficult weighted CSP instances on many cores. A tree decomposition organizes cost functions in a tree of collection of functions called clusters. By processing the tree from the leaves up to the root, we solve each cluster concurrently, for each assignment of its separator, using a state-of-the-art exact sequential algorithm. The grain of parallelism obtained in this way is directly related to the tree decomposition used. We use a dedicated strategy for building suitable decompositions.

We present preliminary results of our prototype running on a cluster with hundreds of cores on different decomposable real problems. This implementation allowed us to solve the last open CELAR radio link frequency assignment instance to optimality.


Setup Time Constraint Satisfaction Problem Tree Decomposition Separator Space Elimination Algorithm 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • David Allouche
    • 1
  • Simon de Givry
    • 1
  • Thomas Schiex
    • 1
  1. 1.Unité de Biométrie et Intelligence Artificielle, UR 875, INRACastanet TolosanFrance

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