Seminar on Modeling June 2015 - Hélène Coullon: Implicitly-parallel programming model for mesh-based numerical simulatio

With the heterogeneity of modern parallel architectures, and with the democratization of parallel hardware in our day to day life, scientific applications has become, in the past few years, a complex HPC-centric development science. However, numericians are not computer-scientists, and even if some of them follow parallelization courses, the complexity of modern architectures and the needed knowledge on low level programming represent too much work and time to actually reach the performance peak of a given machine.
As a result, one of the main research topic of HPC is to find how to abstract intricate details of HPC programming to non-specialists. Some HPC programming models try to solve general problems, but most of the time to stay efficient, those models do not totally hide parallelization but simplify it. On the other hand, some HPC programming models try to make transparent or implicit the parallelization of codes. In this case, though, the model has to be specialized to a specific domain where parallelization technics are known and can be applied transparently.
I will present SIPSim (Structured Implicit Parallelism for scientific SIMulations), an implicitly-parallel programming model for mesh-based numerical simulations. This model proposes the good balance to keep a sequential programming style, and thus the development freedom searched by numericians, while obtaining a transparent high performance simulation on distributed memory architectures, such as clusters. I will also show that this model can be applied to more complex multi-physics simulations. The parallelization of two real case simulations will be presented using two implementations of the SIPSim model, one on a water flow simulation on 2D surfaces, the second one on an arterial blood flow simulation. Finally, I will open this work to the use of component and workflow models to implement the SIPSim model.