LANS Informal Seminar
"Recent computational results on classical DFT of electrolytes: PETSc + PyCUDA"
DATE: May 26, 2010
TIME: 15:00:00 - 16:00:00 Description:
SPEAKER: Dmitry Karpeev, MCS
LOCATION: Bldg 240, Conference Center (1406-1407), Argonne National Laboratory
I will discuss our recent work on calculation of ion density profiles in confined geometries using the classical density functional theory framework. Essentially, the problem here is that of minimization of a highly nonlinear functional that describes the (near) equilibrium profiles of charged hard sphere liquids. This is a computationally intensive problem integro differential problem that is poorly amenable to treatment with Newton's method. In particular, the most computationally-expensive step results from an application of a "pseudo-convolution" operator within a continuation loop. In order to accelerate this computation we devised a spectral quadrature approach, which is well-suited for GPU acceleration and doesn't suffer from the use of single-precision arithmetic. Coupling our original PETSc DFT code to PyCUDA resulted in a substantial acceleration of the overall calculation and enabled substantially more interesting computations.
I will outline the DFT model of ionic channel permeation, outline our computational approach to it and discuss the CUDA-based results and their incorporation into the PETSc framework.
This is joint work with Matthew Knepley (UofC), Peter Brune (UofC) and Dirk Gillespie (Rush).
TIME: 15:00:00 - 16:00:00
Please send questions or suggestions to Debojyoti Ghosh: ghosh at mcs dot anl dot gov.