Title
A Parallel Strategy For Density Functional Theory Computations On Accelerated Nodes
Abstract
Using the Lowdin orthonormalization of tall-skinny matrices as a proxy-app for wavefunction-based Density Functional Theory solvers, we investigate a distributed memory parallel strategy focusing on Graphics Processing Unit (GPU)-accelerated nodes as available on some of the top ranked supercomputers at the present time. We present numerical results in the strong limit regime, as it is particularly relevant for First-Principles Molecular Dynamics. We also examine how matrix product-based iterative solvers provide a competitive alternative to dense eigensolvers on GPUs, allowing to push the strong scaling limit of these computations to a larger number of distributed tasks. Our strategy, which relies on replicated Gram matrices and efficient collective communications using the NCCL library, leads to a time-to-solution under 0.5 s for the Lowdin orthonormalization of a tall-skinny matrix of 3000 columns on Summit at Oak Ridge Leadership Facility (OLCF). Given the similarity in computational operations between one iteration of a DFT solver and this proxy-app, this shows the possibility of solving accurately the DFT equations well under a minute for 3000 electronic wave functions, and thus perform First-Principles molecular dynamics of physical systems much larger than traditionally solved on CPU systems.
Year
DOI
Venue
2020
10.1016/j.parco.2020.102703
PARALLEL COMPUTING
Keywords
DocType
Volume
Dense eigenvalue problem, Distributed numerical linear algebra, Lowdin orthonormalization, Density functional theory, Schulz iteration, GPU acceleration
Journal
100
ISSN
Citations 
PageRank 
0167-8191
0
0.34
References 
Authors
0
4
Name
Order
Citations
PageRank
Massimiliano Lupo Pasini141.54
Bruno Turcksin251.47
Wenjun Ge300.34
Jean-luc Fattebert4467.89