MiniApp for Density Matrix Renormalization Group Hamiltonian Application Kernel

Conference · Sat Sep 01 04:00:00 EDT 2018

DOI:https://doi.org/10.1109/CLUSTER.2018.00075· OSTI ID:1484995

Elwasif, Wael ^[1]; D'azevedo, Ed ^[1]; Chatterjee, Ronnie ^[1]; Alvarez, Gonzalo ^[1]; Hernandez Mendoza, Oscar ^[1]; Sarkar, Vivek ^[2]

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1. ORNL
2. Georgia Institute of Technology, Atlanta

We present two miniapps that implement the core computational kernel of the DMRG++ application, a generic C++ code that implements the Density Matrix Renormalization Group (DMRG) algorithm. The DMRG++ core Kronecker multiplication kernel is formulated using a batched BLAS approach, with implementation that targets both multi-core CPUs using OpenMP and GPGPU using the MAGMA library. The kernel evaluates the matrix-vector multiplication of the target Hamiltonian matrix used in Lanczos algorithm for computing the lowest eigenvalue and eigenvector. The Hamiltonian matrix is expressed compactly as sums of Kronecker products of small dense matrices. We demonstrate improved performance of the miniapp on synthetic problem, and show the performance of the DMRG++ application using a plugin based on the miniapp. We also present an OpenMP miniapp that explores the use of nested parallel constructs to implement the Kronecker multiplication kernel, exploring the use of nested OpenMP worksharing and tasking abstractions to implement the multi-level parallel multiplication algorithm. The miniapp has been used as a co-design vehicle for evaluating features in the OpenMP-4.5 and upcoming OpenMP-5.0 standards.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1484995
• Country of Publication: United States
• Language: English