Parallelization-in-time

Universität Stuttgart
Fakultät für Informatik, Elektrotechnik und Informationstechnik
Fakultätskolloquium im WS 2015/2016
Pfaffenwaldring 47, Hörsaal V.47.03, 70569 Stuttgart-Vaihingen
jeweils am Dienstag, 16:00 Uhr s. t.
Im Rahmen des Fakultäts-Kolloquiums
spricht am 10.11.2015
Dr. Martin Schreiber (University of Exeter)
zum Thema
Parallelization-in-time for climate and weather simulations
Kurzbeschreibung
Over the last decade, the key component for increasing the compute performance for HPC
systems was an increase in data parallelism.
However, for simulations with a fixed problem size, this increase in data parallelism clearly
leads to circumstances with respect to the communication latency. It dominates the overall
compute time, which again results in a stagnation or even decline of scalability.
For weather simulations, further requirements on the wallclock time restrictions are given.
Exceeding these restrictions would make the simulation results outdated and thus less
beneficial.
In this circumstance, time-parallelism is a possible way.
In fact, time-parallel techniques have been studied for over 50 years and have been
successfully applied when the stiffness of the underlying PDEs is dissipative. Recent
advances also address oscillatory stiffness, making time-parallel techniques relevant to
weather and climate simulations. This contribution is about our recent results and methods
on applying the Parareal approach as one of the parallelization-in-time methods to a
prototype of numerical weather simulations.