370.mgrid331
SPEC OMP2012 Benchmark Description File

Benchmark Name

370.mgrid331

Benchmark Author

Eric Barszcz, Paul O Frederickson, A. Woo, M. Yarrow, H. Jin

Benchmark Program General Category

Computational Fluid Dynamics

Benchmark Description

MG demonstrates the capabilities of a very simple multigrid solver in computing a three dimensional potential field. This version is derived from the NPB 3.3.1 benchmark suite.

Input Description

Input parameters are supplied in the file mg.input.

1. lt - amount of multigrid accepted
2. nx, ny, nz - size of the grid
3. nit - number of iterations
4. debug_vec(8) - used for debug printing if not zero

For the benchmark, the debug_vec is not used and set to zero. The test data set uses a 64x64x128 grid, 50 iterations and lt=7. For the train data set, 128x64x256 grid, 100 iterations and lt=8. The reference data set has a 512x256x4096 grid, 700 iterations and lt=10.

Output Description

In addition to echoing some of the inputs, the main part of the output is from the smoothed approximate inverse. Only a small fraction of the smoothed output is printed, just enough to assure that all work is being done and at to check intermediate results for accuracy. In addition the L2 norm and Inf norms are are used as a checksum of the output.

Programming Language

FORTRAN

Known portability issues

None

Reference

Bailey, D.; Harris, T.; Saphir, W.; van der Wijngaart, R.; Woo, A.; Yarrow, M. (December 1995), "The NAS Parallel Benchmarks 2.0", NAS Technical Report NAS-95-020, NASA Ames Research Center, Moffett Field, CA

Jin, H.; Frumkin, M.; Yan, J. (October 1999), "The OpenMP Implementation of NAS Parallel Benchmarks and Its Performance", NAS Technical Report NAS-99-011, NASA Ames Research Center, Moffett Field, CA