Exact Dependence Analysis for Increased Communication Overlap

  • Simone Pellegrini
  • Torsten Hoefler
  • Thomas Fahringer
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7490)


MPI programs are often challenged to scale up to several million cores. In doing so, the programmer tunes every aspect of the application code. However, for large applications, this is often not practical and expensive tracing tools and post-mortem analysis are employed to guide the tuning efforts finding hot-spots and performance bottlenecks. In this paper we revive the use of compiler analysis techniques to automatically unveil opportunities for communication/computation overlap using the result of exact data dependence analysis provided by the polyhedral model. We apply our technique to a 5-point stencil code showing performance improvements up to 28% using 512 cores.


Message passing Compiler Analysis Data Dependence Analysis Polyhedral Model 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Simone Pellegrini
    • 1
  • Torsten Hoefler
    • 2
    • 3
  • Thomas Fahringer
    • 1
  1. 1.Institute of InformaticsUniversity of InnsbruckAustria
  2. 2.University of Illinois at Urbana-ChampaignUSA
  3. 3.Department of Computer ScienceETH ZurichSwitzerland

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