Spin Summations: A High-Performance Perspective

05/18/2017
by   Paul Springer, et al.
0

Besides tensor contractions, one of the most pronounced computational bottlenecks in the non-orthogonally spin-adapted forms of the quantum chemistry methods CCSDT and CCSDTQ, and their approximate forms---including CCSD(T) and CCSDT(Q)---are spin summations. At a first sight, spin summations are operations similar to tensor transpositions; a closer look instead reveals additional challenges to high-performance calculations, including temporal locality as well as scattered memory accesses. This publication explores a sequence of algorithmic solutions for spin summations, each exploiting individual properties of either the underlying hardware (e.g. caches, vectorization), or the problem itself (e.g. factorizability). The final algorithm combines the advantages of all the solutions, while avoiding their drawbacks; this algorithm, achieves high-performance through parallelization, vectorization, and by exploiting the temporal locality inherent to spin summations. Combined, these optimizations result in speedups between 2.4x and 5.5x over the NCC quantum chemistry software package. In addition to such a performance boost, our algorithm can perform the spin summations in-place, thus reducing the memory footprint by 2x over an out-of-place variant.

READ FULL TEXT
research
04/22/2020

A Submatrix-Based Method for Approximate Matrix Function Evaluation in the Quantum Chemistry Code CP2K

Electronic structure calculations based on density-functional theory (DF...
research
03/07/2016

TTC: A high-performance Compiler for Tensor Transpositions

We present TTC, an open-source parallel compiler for multidimensional te...
research
05/03/2017

cuTT: A High-Performance Tensor Transpose Library for CUDA Compatible GPUs

We introduce the CUDA Tensor Transpose (cuTT) library that implements hi...
research
06/29/2023

NNQS-Transformer: an Efficient and Scalable Neural Network Quantum States Approach for Ab initio Quantum Chemistry

Neural network quantum state (NNQS) has emerged as a promising candidate...
research
06/10/2021

Classical algorithms and quantum limitations for maximum cut on high-girth graphs

We study the performance of local quantum algorithms such as the Quantum...
research
05/01/2022

Lifetime-based Method for Quantum Simulation on a New Sunway Supercomputer

Faster classical simulation becomes essential for the validation of quan...
research
03/16/2021

Reducing Redundancy in Data Organization and Arithmetic Calculation for Stencil Computations

Stencil computation is one of the most important kernels in various scie...

Please sign up or login with your details

Forgot password? Click here to reset