SGEFA_OPEN_MP
Sequential and OpenMP versions of Linpack Solver

SGEFA_OPEN_MP is a C++ program which reimplements the SGEFA/SGESL linear algebra routines from LINPACK for use with OpenMP.

Right now, running for N = 10, 100 and 1000, but only using a 2 Processor Apple G5, the parallel code is not doing well at all. I will try to find out what is holding it back.

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SGEFA_OPEN_MP is also available in a C version and a FORTRAN77 version and a FORTRAN90 version.

Reference:

1. Peter Arbenz, Wesley Petersen,
   Introduction to Parallel Computing - A practical guide with examples in C,
   Oxford University Press,
   ISBN: 0-19-851576-6,
   LC: QA76.58.P47.
2. Rohit Chandra, Leonardo Dagum, Dave Kohr, Dror Maydan, Jeff McDonald, Ramesh Menon,
   Parallel Programming in OpenMP,
   Morgan Kaufmann, 2001,
   ISBN: 1-55860-671-8,
   LC: QA76.642.P32.
3. Barbara Chapman, Gabriele Jost, Ruud vanderPas, David Kuck,
   Using OpenMP: Portable Shared Memory Parallel Processing,
   MIT Press, 2007,
   ISBN13: 978-0262533027,
   LC: QA76.642.C49.
4. Jack Dongarra, Jim Bunch, Cleve Moler, Pete Stewart,
   LINPACK User's Guide,
   SIAM, 1979,
   ISBN13: 978-0-898711-72-1,
   LC: QA214.L56.
5. Charles Lawson, Richard Hanson, David Kincaid, Fred Krogh,
   Algorithm 539: Basic Linear Algebra Subprograms for Fortran Usage,
   ACM Transactions on Mathematical Software,
   Volume 5, Number 3, September 1979, pages 308-323.

Source Code:

• sgefa_open_mp.C, the source code.
• sgefa_open_mp.csh, commands to compile, link and run the source code.
• sgefa_open_mp_output.txt, the output file.

List of Routines:

• MAIN is the main program for the SGEFA_OPEN_MP test program.
• TEST01 runs the sequential version of SGEFA.
• TEST02 runs the parallel version of SGEFA.
• TEST03 runs the parallel version of SGEFA in sequential mode.
• ISAMAX finds the index of the vector element of maximum absolute value.
• MATGEN generates a "random" matrix for testing.
• MSAXPY carries out multiple "SAXPY" operations.
• MSAXPY2 carries out multiple "SAXPY" operations.
• MSGEFA factors a matrix by gaussian elimination.
• MSGEFA2 factors a matrix by gaussian elimination.
• SAXPY computes float constant times a vector plus a vector.
• SDOT forms the dot product of two vectors.
• SGEFA factors a double precision matrix by gaussian elimination.
• SGESL solves a real general linear system A * X = B.
• SSCAL scales a float vector by a constant.
• SSWAP interchanges two float vectors.
• TIMESTAMP prints the current YMDHMS date as a time stamp.

You can go up one level to the C++ source codes.