Novel Models for Or-Parallel Logic Programs: A Performance Analysis

Vítor Santos Costa, Ricardo Rocha and Fernando Silva

August 2000


One of the advantages of logic programming is the fact that it offers many sources of {\em implicit} parallelism, such as and-parallelism and or-parallelism. Arguably, or-parallel systems, such as Aurora and Muse, have been the most successful parallel logic programming systems so far. Or-parallel systems rely on techniques such as Environment Copying to address the problem that branches being explored in parallel may need to assign different bindings for the same shared variable. Recent research has led to two new binding representation approaches that also support independent and-parallelism: the Sparse Binding Array and the Copy-On-Write binding models. In this paper, we investigate whether these newer models are practical alternatives to copying for or-parallelism. We based our work on YapOr, an or-parallel copying system using the YAP Prolog engine, so that the three alternative systems share schedulers and the underlying engine.


  author =    {V. Santos Costa and R. Rocha and F. Silva},
  title =     {{Novel Models for Or-Parallel Logic Programs: A Performance Analysis}},
  booktitle = {Proceedings of the 6th International Euro-Par Conference (Euro-Par 2000)},
  pages =     {744--753},
  number =    {1900},
  series =    {LNCS},
  publisher = {Springer},
  editor =    {A. Bode and T. Ludwig and W. Karl and R. Wismüller},
  month =     {August/September},
  year =      {2000},
  address =   {Munich, Germany},

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