Java on networks of workstations (JavaNOW): a parallel computing frameworkinspired by Linda and the Message Passing Interface (MPI)

Networks of workstations are a dominant force in the distributed computing arena, due primarily to the excellent price/performance ratio of such syste ms when compared to traditionally massively parallel architectures. It is t herefore critical to develop programming languages and environments that ca n help harness the raw computational power available on these systems. In t his article, we present JavaNOW (Java on Networks of Workstations), a Java- based framework for parallel programming on networks of workstations. It cr eates a virtual parallel machine similar to the MPI (Message Passing Interf ace) model, and provides distributed associative shared memory similar to t he Linda memory model but with a richer set of primitive operations. JavaNOW provides a simple yet powerful framework for performing computation on networks of workstations. In addition to the Linda memory model, it pro vides for shared objects, implicit multithreading, implicit synchronization , object dataflow, and collective communications similar to those defined i n MPI. JavaNOW is also a component of the Computational Neighborhood, a Jav a enabled suite of services for desktop computational sharing. The intent o f JavaNOW is to present an environment for parallel computing that is both expressive and reliable and ultimately can deliver good to excellent perfor mance. As JavaNOW is a work in progress, this article emphasizes the expres sive potential of the JavaNOW environment and presents preliminary performa nce results only. Copyright (C) 2000 John Wiley & Sons, Ltd.