MM5 Model V2

V2 Timing Results
   SESAME Case
   World Series

Pre & Post Processing V2

V2 Source Code

V2 Tutorial Notes

Testing/Benchmarking : SESAME Case

The data specified in these tables is for a small domain MM5 12-h forecast (known as the SESAME squall). The values listed are the elapsed time in seconds to complete the foreast (using the UNIX timex utility). Several different Compaq architectures were tested: DPW (the workstations), the 4100 pedestals and the 8400. The current default compiler options as well as a more aggressive set of compiler options were tested. Finally, the effect of using the OpenMP option for parallel processing was tested. Virtually no difference was found between f77 and f90, given the same compiler flags on the same architecture.

The machines were not in single user mode, though the CPU utilization was less than 1% throughout the testing. For this application, the most sensitive factor was the architecture (single processor 4100 6-10% faster than the single processor DPW and 8400), followed by compiler options (2-4% difference between the current default options used in the model and the best set found so far), and finally OpenMP (approximately 1% hit for OpenMP overhead when comparing single processor runs).

The data in this table is for the no OpenMP set. Therefore, only a single processor is run.

Data for this table include the effects of OpenMP, allowing multiple processor runs. Parallel speed-up is computed by the computing the ratio of the single-processor elapsed time to the multiple-processor elapsed time.