Linear algebra subprograms on shared memory computers: Beyond LAPACK

  • Stefano Salvini
  • Jerzy Waśniewski
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1184)


This paper discusses the implementation of LAPACK routines on a cache-based, shared memory system. The shortcomings of an approach which relies on parallelized BLAS are illustrated in the cases of LU, Cholesky and QR factorizations. An alternative approach to these factorization routines, exploiting explicit parallelism at a higher level in the code, is reported: this provides higher scalability and efficiency in all cases studied. Issues of portability were addressed by using standard Fortran 77 and PCF compiler directives in all codes.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • Stefano Salvini
    • 1
  • Jerzy Waśniewski
    • 2
  1. 1.The Numerical Algorithms Group LtdOxfordUK
  2. 2.Computing Centre for Reasearch and EducationUNI•C, DTULyngbyDenmark

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