Parallelizing ROMS for Distributed Memory Machines using SMS


Daniel S. Schaffer

NOAA/ERL/Forecast Systems Lab

Boulder, USA




The National Oceanographic and Atmospheric Administration Forecast Systems Laboratory (FSL) has developed a directive-based tool for parallelizing weather and ocean models. The user inserts directives in the form of comments into existing FORTRAN code. SMS translates the code and directives into a parallel version that runs efficiently on both distributed and shared memory machines.

Here we describe the SMS tool and show how it has been used to parallelize a Northeast Pacific scenario of the ROMS model. The parallel code is currently being run in production on FSL's cluster of Alpha workstations. Analysis of the parallel scalablity is given. Plans to handle distributed memory parallelization of a nested ROMS and a coupled COAMPS/ROMS model are discussed.