Title
Embracing a new era of highly efficient and productive quantum Monte Carlo simulations
Abstract
QMCPACK has enabled cutting-edge materials research on supercomputers for over a decade. It scales nearly ideally but has low single-node efficiency due to the physics-based abstractions using array-of-structures objects, causing inefficient vectorization. We present a systematic approach to transform QMCPACK to better exploit the new hardware features of modern CPUs in portable and maintainable ways. We develop miniapps for fast prototyping and optimizations. We implement new containers in structure-of-arrays data layout to facilitate vectorizations by the compilers. Further speedup and smaller memory-footprints are obtained by computing data on the fly with the vectorized routines and expanding single-precision use. All these are seamlessly incorporated in production QMCPACK. We demonstrate upto 4.5x speedups on recent Intel® processors and IBM Blue Gene/Q for representative workloads. Energy consumption is reduced significantly commensurate to the speedup factor. Memory-footprints are reduced by up-to 3.8x, opening the possibility to solve much larger problems of future.
Year
DOI
Venue
2017
10.1145/3126908.3126952
SC
Keywords
DocType
Volume
QMC,vectorization,optimizations,portability,CPUs
Journal
abs/1708.02645
ISSN
ISBN
Citations 
2167-4329
978-1-4503-5114-0
0
PageRank 
References 
Authors
0.34
4
6
Name
Order
Citations
PageRank
Amrita Mathuriya111.40
Ye Luo201.01
Raymond Clay310.74
Anouar Benali421.10
Luke Shulenburger5141.71
Jeongnim Kim651.60