We have previously introduced a common metric for measuring relative development time productivity of HPC software development. The RDTP metric has been applied to data from benchmark codes and classroom experiments, with consistent trends for various programming models.
In general the results support the theory that traditional HPC programming models such as MPI yield good speedup but require more relative effort than other implementations (Figure 5). OpenMP generally provides speedup comparable to MPI, but requires less effort. This leads to higher values of the RDTP metric. There are questions of scalability with regard to OpenMP that are not addressed by this study.
The pMatlab implementations of HPC Challenge provide an example of a language that can yield good speedup for some problems, while requiring less relative effort, again leading to higher values of the RDTP metric.
Further classroom experiments are planned, and as more data is collected it will be analyzed in the same manner, to see if other trends emerge. Our current work is focused on designing a standard framework for automating the collection, storage, and analysis of workflow data (see “Modeling HPC workflows with timed Markov models” in this issue).
2Kepner, J. “HPC Productivity Model Synthesis.” IJHPCA Special Issue on HPC Productivity, Vol. 18, No. 4, SAGE 2004.
3Funk, A., Basili, V., Hochstein, L., Kepner, J. “Application of a Development Time Productivity Metric to Parallel Software Development.” Second International Workshop on Software Engineering for High Performance Computing Systems Applications. St. Louis, Missouri. May 15, 2005.
4Funk, A., Kepner, J., Basili, V., Hochstein, L. "A Relative Development Time Productivity Metric for HPC Systems." Ninth Annual Workshop on High Performance Embedded Computing. 20 – 22 September 2005, Lexington, MA.
5Wheeler, D. SLOCcount. www.dwheeler.com/sloccount/
6Choy, R., Edelman, A. MATLAB*P 2.0: A unified parallel MATLAB. MIT DSpace, Computer Science collection, Jan. 2003. hdl.handle.net/1721.1/3687
7NAS Parallel Benchmarks - www.nas.nasa.gov/Software/NPB/
8ZPL - www.cs.washington.edu/research/zpl/home/
9Haney, R. et. al. “pMatlab Takes the HPC Challenge.” Poster presented at High Performance Embedded Computing (HPEC) workshop, Lexington, MA. 28-30 Sept. 2004.
10HPC Challenge - icl.utk.edu/hpcc/, www.hpcchallenge.org/