Gauge Field Generation on Large-Scale GPU-Enabled Systems

TL;DR

This paper discusses extending GPU-accelerated lattice QCD algorithms to enable large-scale gauge field generation on supercomputers, demonstrating initial results on TitanDev.

Contribution

It introduces an extension of QDP-JIT to support full gauge field generation on GPU-enabled systems, enabling strong scaling of the Hybrid Monte-Carlo algorithm.

Findings

Successful initial gauge field generation on TitanDev

Extension of QDP-JIT for full gauge field algorithms

Demonstrated strong scaling potential on large GPU systems

Abstract

Over the past years GPUs have been successfully applied to the task of inverting the fermion matrix in lattice QCD calculations. Even strong scaling to capability-level supercomputers, corresponding to O(100) GPUs or more has been achieved. However strong scaling a whole gauge field generation algorithm to this regim requires significantly more functionality than just having the matrix inverter utilizing the GPUs and has not yet been accomplished. This contribution extends QDP-JIT, the migration of SciDAC QDP++ to GPU-enabled parallel systems, to help to strong scale the whole Hybrid Monte-Carlo to this regime. Initial results are shown for gauge field generation with Chroma simulating pure Wilson fermions on OLCF TitanDev.