Space weather simulation
Simulating space weather to predict conditions which can cause disruption of satellite operations, communications, etc., means literally simulating the magnetised plasma that permeates the whole solar system. The code used here is iPIC3D a well-developed and widely used code routinely run on NASA's Pleiades supercomputer and allows studying a large portion of the system while retaining the full detailed microphysics. The main challenge in the Space Weather Simulations is the presence of multiple temporal and spatial scales. Today's Petascale computers do not allow to reach the full scale of the processes required to be simulated due to lack of memory to store all particles and insufficient compute power to make those particles move according to the right physics. The innovative methods included in iPIC3D will be adapted to the DEEP Architecture using software practices previously tested on Roadrunner . The adaptation of iPIC3D to the DEEP Architecture will go far beyond the previous experience thanks to the use of implicit methods that allow the simulation of larger system sizes relevant to space weather and exploit the benefits of the new hardware.
These simulations are done by the Katholieke Universiteit Leuven, Belgium.
"Space weather provides an ideal testbed for the design and experimentation of exascale architectures because two elements form a typical space weather simumation: fields and particles simulation. To increase the fidelity and predictive capability, it is necessary to increase the number of particles and the number of points where the fields are described. The particles evolve as single units and are highly scalable in a parallel hardware, but the fields are highly interconnected and require more communication, providing a greater challenge to parallel scaling and limiting the performance of the whole application when running in tens or hundreds of thousands of cores. DEEP provides a unique opportunity: to take full benefit of the scalable particles on the Booster, while keeping the less computing intensive fields in the Cluster. The particles move and can migrate thanks to the communication between Booster nodes, and communicate the changes in the induced electromagnetic fields to the Cluster. This feature makes DEEP unique and truly interesting for space weather." - Giovanni Lapenta, KULeuven