Estimation of Round-off Errors in OpenMP Codes

  • Pacôme Eberhart
  • Julien Brajard
  • Pierre FortinEmail author
  • Fabienne Jézéquel
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9903)


It is crucial to control round-off error propagation in numerical simulations, because they can significantly affect computed results, especially in parallel codes like OpenMP ones. In this paper, we present a new version of the CADNA library that enables the numerical validation of OpenMP codes. With a reasonable cost in terms of execution time, it enables one to estimate which digits in computed results are affected by round-off errors and to detect numerical instabilities that may occur during the execution. The interest of this new OpenMP-enabled CADNA version is shown on various applications, along with performance results on multi-core and many-core (Intel Xeon Phi) architectures.


CADNA library Discrete stochastic arithmetic Floating-point arithmetic Numerical validation Multi-core architectures Many-core architectures OpenMP Round-off error 



The authors thank Pierre-Emmanuel Le Roux (LIP6) for managing the compute servers, and Philippe Thierry (Intel) for providing the Intel compiler (2017-beta). They also thank the reviewers for their helpful comments.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Pacôme Eberhart
    • 1
  • Julien Brajard
    • 2
    • 3
  • Pierre Fortin
    • 1
    Email author
  • Fabienne Jézéquel
    • 1
    • 4
  1. 1.Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 7606, LIP6ParisFrance
  2. 2.Sorbonne Universités, UPMC Univ Paris 06, CNRS-IRD-MNHN, LOCEANParisFrance
  3. 3.Inria ParisParisFrance
  4. 4.Université Panthéon-AssasParis, Cedex 05France

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