Improved Multi-Core Nested Depth-First Search

  • Sami Evangelista
  • Alfons Laarman
  • Laure Petrucci
  • Jaco van de Pol
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7561)


This paper presents Cndfs, a tight integration of two earlier multi-core nested depth-first search (Ndfs) algorithms for LTL model checking. Cndfs combines the different strengths and avoids some weaknesses of its predecessors. We compare Cndfs to an earlier ad-hoc combination of those two algorithms and show several benefits: It has shorter and simpler code and a simpler correctness proof. It exhibits more robust performance with similar scalability, while at the same time reducing memory requirements.

The algorithm has been implemented in the multi-core backend of the LTSmin model checker, which is now benchmarked for the first time on a 48 core machine (previously 16). The experiments demonstrate better scalability than other parallel LTL model checking algorithms, but we also investigate apparent bottlenecks. Finally, we noticed that the multi-core Ndfs algorithms produce shorter counterexamples, surprisingly often shorter than their BFS-based counterparts.


Linear Temporal Logic Linear Time Temporal Logic Work Thread Model Check Tool Core Machine 
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

  • Sami Evangelista
    • 1
  • Alfons Laarman
    • 2
  • Laure Petrucci
    • 1
  • Jaco van de Pol
    • 2
  1. 1.LIPN, CNRS UMR 7030Université Paris 13France
  2. 2.Formal Methods and ToolsUniversity of TwenteThe Netherlands

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