CISL Brown Bag Seminar: "Creating Abstractions for Radiation Transport Codes Targeting Heterogeneous Systems"

10/09/2018 - 12:00pm
ML Chapman Room

Creating Abstractions for Radiation Transport Codes Targeting Heterogeneous Systems

Robert Searles
University of Delaware

Architectures are rapidly evolving, and exascale machines are expected to offer billion-way concurrency. We need to rethink algorithms, languages and programming models among other components in order to migrate large scale applications and explore parallelism on these machines. Although directive-based programming models allow programmers to worry less about programming and more about science, expressing complex parallel patterns in these models can be a daunting task especially when the goal is to match the performance that the hardware platforms can offer. One such pattern is wavefront. This talk extensively studies a wavefront-based miniapplication for Denovo, a production code for nuclear reactor modeling. We parallelize the Koch-Baker-Alcouffe (KBA) parallel-wavefront sweep algorithm in the main kernel of Minisweep (the miniapplication) using CUDA, OpenMP and OpenACC. Our OpenACC implementation running on NVIDIA’s nextgeneration Volta GPU boasts an 85.06x speedup over serial code, which is larger than CUDA’s 83.72x speedup over the same serial implementation. Our experimental platform includes SummitDev, an ORNL representative architecture of the Summit supercomputer. This talk will also cover a brief overview of Robert’s other projects, including topics such as high-level language auto-tuning and high-level graph analytics acceleration utilizing a combination of MapReduce and CUDA.

Tuesday, October 9, 2018
12:00 p.m. - 1:00 p.m.
Mesa Lab, Chapman Room
Bring your lunch!