Scaling Hierarchical N-Body Simulations on GPU Clusters
SESSION: GPGPU Performance
EVENT TYPE: Paper
TIME: 1:30PM - 2:00PM
SESSION CHAIR: Gerhard Wellein
AUTHOR(S):Pritish Jetley, Lukasz Wesolowski, Filippo Gioachin, Laxmikant V. Kale, Thomas R. Quinn
ROOM:391-392
ABSTRACT: This paper focuses on the use of clusters of use of GPGPU-based clusters
for hierarchical N-body simulations. Whereas the behavior of these hierarchical methods has been studied in the past on CPU-based architectures, we investigate key performance issues in the context of clusters of GPUs. These include kernel organization and efficiency, the balance between tree traversal and force computation work, grain size selection through the tuning of offloaded work request sizes, and the reduction of sequential bottlenecks. The effect of various application parameters is modeled and experiments are carried out to quantify gains in performance. Our studies are carried out in the context of a production-quality parallel cosmological simulator called ChaNGa. We highlight the re-engineering of the application to make it more suitable for GPU-based environments. Finally, we present scaling performance results from experiments on the NCSA Lincoln GPU cluster.
Chair/Author Details:
Gerhard Wellein (Chair) - Erlangen Regional Computing Center
Pritish Jetley - University of Illinois at Urbana-Champaign
Lukasz Wesolowski - University of Illinois at Urbana-Champaign
Filippo Gioachin - University of Illinois at Urbana-Champaign
Laxmikant V. Kale - University of Illinois at Urbana-Champaign
