With the proliferation of high performance workstations and the current trend towards high speed communication networks. the cumulative computing power provided by a group of general purpose workstations is comparable to supercomputers. However a number of obstacles have to be overcome before the full potential of these network-based distributed systems can be exploited. This paper investigates the requirements of current workstation clusters interconnected by local area networks (LANs) which would allow them to be used as platforms for high performance distributed computing. The blocked LU decomposition of dense matrices is used as the running example in the presented study. Performance of this algorithm is measured on the iPSC/860 hypercube and on a set of homogeneous workstations (SUN SPARCstation 1+) interconnected by Ethernet. These measures are analyzed and a set of requirements are identified which would enable a network of workstations to deliver high performance distributed computing.>

The authors present the parallelization of blocked algorithms for LU factorization. They isolate problems inherent in sequential blocked algorithms and provide approaches to overcome them on distributed memory architectures. The performances of the parallelized versions of three blocked algorithms suited to column oriented Fortran are compared. Experiments are performed on the iPSC/860 hypercube. It is shown that it is not intuitively clear which algorithm might perform best on a given architecture; this is dependent on the problem size and the number of available parameters.>