Revisiting Clause Exchange in Parallel SAT Solving

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7317)


Managing learnt clause database is known to be a tricky task in SAT solvers. In the portfolio framework, the collaboration between threads through learnt clause exchange makes this problem even more difficult to tackle. Several techniques have been proposed in the last few years, but practical results are still in favor of very limited collaboration, or even no collaboration at all. This is mainly due to the difficulty that each thread has to manage a large amount of learnt clauses generated by the other workers. In this paper, we propose new efficient techniques for clause exchanges within a parallel SAT solver. In contrast to most of the current clause exchange methods, our approach relies on both export and import policies, and makes use of recent techniques that proves very effective in the sequential case. Extensive experimentations show the practical interest of the proposed ideas.


Unit Clause Small Clause Multicore Architecture Sequential Solver Export Strategy 
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 2012

Authors and Affiliations

  1. 1.Université Lille-Nord de France, CRIL - CNRS UMR 8188LensFrance
  2. 2.Institute for Formal Models and VerificationJohannes Kepler UniversityLinzAustria

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