Molecular dynamics beyonds the limits: massive scaling on 72 racks of a BlueGene/P and supercooled glass transition of a 1 billion particles system

TL;DR

This paper presents a highly scalable molecular dynamics simulation code capable of handling 1 billion particles on a supercomputer, enabling unprecedented studies of structural glasses and the liquid-glass transition.

Contribution

The development and demonstration of a massively parallel molecular dynamics code that scales efficiently to 72 racks of BlueGene/P, allowing billion-particle simulations.

Findings

Achieved 89% efficiency on 72 racks of BlueGene/P

Simulated 1 billion particles with less than 0.14 seconds per iteration

Enabled detailed study of the liquid-glass transition in large systems

Abstract

We report scaling results on the world's largest supercomputer of our recently developed Billions-Body Molecular Dynamics (BBMD) package, which was especially designed for massively parallel simulations of the atomic dynamics in structural glasses and amorphous materials. The code was able to scale up to 72 racks of an IBM BlueGene/P, with a measured 89% efficiency for a system with 100 billion particles. The code speed, with less than 0.14 seconds per iteration in the case of 1 billion particles, paves the way to the study of billion-body structural glasses with a resolution increase of two orders of magnitude with respect to the largest simulation ever reported. We demonstrate the effectiveness of our code by studying the liquid-glass transition of an exceptionally large system made by a binary mixture of 1 billion particles.