Efficient parallel implementation of the ChASE library on distributed CPU-GPU architectures

摘要

The Chebyshev Accelerated Subspace iteration Eigensolver (ChASE) is an iterative eigensolver developed at the JSC by the SimLab ab initio. The solver target principally sequences of dense eigenvalue problems as they arise in Density functional Theory, but can also work on the single eigenproblem. ChASE leverages on the preponderant use of BLAS 3 subroutines to achieve close-to-peak performance. Currently, the library can be executed in parallel on many- and multi-core platforms. The latest development of this project dealt with the extension of the CUDA build to encompass multiple GPUs on distinct CPUs. As such this hybrid parallelization will use MPI as well as CUDA interfaces effectively exploiting heterogeneous multi-GPU platforms. The extended library was tested on large and dense eigenproblems extracted from excitonic Hamiltonian. The ultimate goal is to integrate this new parallel implementation of ChASE with the VASP-BSE code.