16:00 Real-Time Tsunami Simulation Solving the Shallow Water Equations on Multi-Node GPU Cluster – M. Arce Acuna (Tokyo Tech)

Tsunamis are destructive forces of nature and thus their accurate forecast and early warning is extremely important. In order to predict a Tsunami the Shallow Water Equations must be solved in real-time. With the introduction of GPGPU, a new revolution has been opened in high performance computing. We used CUDA to compute the simulation on the GPU which drastically accelerated the computation. A single-GPU calculation had been found to be 62-times faster than using a single CPU core. Moreover the domain was decomposed and solved on a multi-node GPU cluster. Overlapping transfers and computation further accelerated the process by hiding communication. For the GPU transfers an asynchronous copy model was used. The MPI library was used to transfer the data between nodes.  A domain representing real bathymetry, with grid size 4096×8192 was used as our dataset. Our tests on TSUBAME showed excellent scalability. Results for CPU and GPU scalability are presented.