Improving ABT Performance by Adding Synchronization Points

  • Ismel Brito
  • Pedro Meseguer
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5129)


Asynchronous Backtracking (ABT) is a reference algorithm for Distributed CSP (DisCSP). In ABT, agents assign values to their variables and exchange messages asynchronously and concurrently. When an ABT agent sends a backtracking message, it continues working without waiting for an answer. In this paper, we describe a case showing that this strategy may cause some inefficiency. To overcome this, we propose ABThyb, a new algorithm that results from adding synchronization points to ABT. We prove that ABThyb is correct, complete and terminates. We also provide an empirical evaluation of the new algorithm on several benchmarks. Experimental results show that ABThyb outperforms ABT.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Ismel Brito
    • 1
  • Pedro Meseguer
    • 1
  1. 1.IIIA, Institut d’Investigació en Intel.ligència ArtificialCSIC, Consejo Superior de Investigaciones CientíficasBellaterraSpain

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