The computing community needs distributed systems to satisfy its need for harnessing more computers solving more problems more quickly. Yet is still hard for programmers to write programs for such systems. Recently, configuration languages have emerged which have the aim of making distributed programming easier, more robust and more flexible. So far, each of these is confined to a small user community, and there is a wide range of features and facilities offered. In this paper, we consider the basic responsibilities of configuration languages and then look at four sample languages in detail. These are Darwin, Durra, PCL and Polylith. The study starts with simple static configuration programming and proceeds to dynamic programming and change management. The producer consumer example is used throughout, and the comparative code fragments shown are a novel feature of the paper. From the results of the comparison we deduce a ten-point scheme of criteria for evaluating a language in terms o...

15 Preface 19 Acknowledgements 22 1 Introduction 24 1.1 Background : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 24 1.2 Motivation and Objectives : : : : : : : : : : : : : : : : : : : : : : 24 1.3 Structure of the Thesis : : : : : : : : : : : : : : : : : : : : : : : : 25 1.3.1 Related Publications : : : : : : : : : : : : : : : : : : : : : 27 2 The Quest for High Performance 28 2.1 Introduction : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 28 2.2 Bit and Instruction Level Parallelism : : : : : : : : : : : : : : : : 29 2.3 Reduced Instruction Set Computers : : : : : : : : : : : : : : : : : 30 2.4 The Limits of Sequential Computation : : : : : : : : : : : : : : : 31 2.5 Parallel Computer Architectures : : : : : : : : : : : : : : : : : : : 32 2.5.1 SIMD : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 33 2.5.2 MIMD : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 34 2.5.2.1 Shared Memory MIMD Architectures : : : : : : : 34 2.5.2.2 Distributed M...

processing. The ultimate message from this work should be seen in a larger context. Several languages---such as Ada and Modula-2---are being touted as the standards for the 1990s. These languages severely restrict parallel programming style; this may make saving dusty decks by preprocessing an impossibility. KEY WORDS Parallel programming C CSP Compiler design Distributed systems 0038--0644/92/050371--20$10.00 Received 13 December 1989 1992 by John Wiley & Sons, Ltd. Revised 16 December 1991 372 D. E. STEVENSON ET AL. INTRODUCTION In September 1986, Clemson University purchased a Floating Point Systems (FPS) T-series computer. The T is a hypercube of vector processors: that is, each node is a vector processor. When the T arrived, it had only the occam I language available. In order to make the T usable for numerical work, at least a Fortran compiler was required; certainly for system work, a C compiler was called for. While FPS and Cornell University had already started down th