Details

Autor(en) / Beteiligte

• Gahvari, Hormozd
• Dobrev, Veselin A.
• Falgout, Robert D.
• Kolev, Tzanio V.
• Schroder, Jacob B.
• Schulz, Martin
• Yang, Ulrike Meier

Titel

A performance model for allocating the parallelism in a multigrid-in-time solver

Ist Teil von

• Proceedings of the 7th International Workshop on Performance Modeling, Benchmarking and Simulation of High Performance Computing Systems, 2016, p.22-31

Ort / Verlag

Piscataway, NJ, USA: IEEE Press

Erscheinungsjahr

2016

Link zum Volltext

Quelle

IEEE Xplore

Beschreibungen/Notizen

• The traditional way to numerically solve time-dependent problems is to sequentially march through time, solving for one time step and then the next. The parallelism in this approach is limited to the spatial dimension, which is quickly exhausted, causing the gain from using more processors to solve a problem to diminish. One approach to overcome this barrier is to use methods that are parallel in time. These methods have the potential to achieve dramatically better performance compared to time-stepping approaches, but achieving this performance requires carefully choosing the amount of parallelism devoted to space versus the amount devoted to time. Here, we present a performance model that, for a multigrid-in-time solver, makes the decision on when to switch to parallel-in-time and on how much parallelism to devote to space vs. time. In our experiments, the model selects the best parallel configuration in most of our test cases and a configuration close to the best one in all other cases.