SPECaccel Benchmark Description File

Benchmark Name


Benchmark Author

Paul N. Swarztrauber

Initial port to OpenMP by Alexander Grund

Benchmark Program General Category


Benchmark Description

Swim is a weather prediction benchmark program for comparing the performance of current supercomputers. The swim code is a finite-difference approximation of the shallow-water equations and is known to be memory bandwidth limited.

Input Description

The ref workload does a 12000x12000 area array of data and iterates over 1500 timesteps.

The train workload does a 2000x2000 area array of data and iterates over 6500 timesteps.

The test workload does a 512x512 area array of data and iterates over 10 timesteps.

Output Description

It prints the diagonal elements of the velocity field.

Programming Language


Known portability issues



Robert Sadourny, The Dynamics of Finite-Difference Models of the Shallow-Water Equations, J. Atm. Sciences, Vol 32, NO 4, April 1975. DOI


G.-R. Hoffmann, P. N. Swarztrauber, and R. A. Sweet, Aspects of using multiprocessors for meteorological modeling, In: Multiprocessing in Meteorological Models, G.-R. Hoffman and D.F. Snelling, eds., Springer-Verlag, 1988, pp. 125-196.

Last updated: 14 December 1999