A comparative study of PVM workstation cluster implementations of a two-phase subsurface flow model

Abstract

Four versions of a message-passing, distributed-memory, distributed-disk multicomputer application for simulating two-phase fluid flow in porous media are studied. The FORTRAN 77 finite element code, solved in parallel using an iterative domain-decomposition method, was ported from a shared-memory multiprocessor implementation to a network of heterogeneous computers using the PVM (Parallel Virtual Machine) software system. Issues concerning the calculation of speedups in cluster computing are discussed, and the performance of the four versions is compared. Parallel efficiencies of up to nearly 60% were achieved using 17 homogeneous networked workstations; speedups were comparable to the shared-memory implementation. We conclude that network multicomputing using PVM is an attractive alternative to hardware multiprocessors for large-grained parallel implementations of computationally intensive problems in hydrology.