The availability of high-speed networks and increasingly powerful commodity microprocessors is making the usage of clusters, or networks, of computers an appealing vehicle for cost effective parallel computing. Clusters, built using Commodity-Off-The-Shelf (COTS) hardware components as well as free, or commonly used, software, are playing a major role in redefining the concept of supercomputing. In this paper we discuss the reasons why COTS-based clusters are becoming popular environments for running supercomputing applications. We describe the current enabling technologies and present four state-of-theart cluster-based projects. Finally, we summarise our findings and draw a number of conclusions relating to the usefulness and likely future of cluster computing. Copyright © 1999 John Wiley & Sons, Ltd. KEY WORDS: commodity components; clusters; message-passing; supercomputing; parallel computing

The Portable, Extensible Toolkit for Scientific computation (PETSc) is a toolbox for the parallel, numerical solution of elliptic and related partial differential equations using finite element, finite difference or related discretization techniques. In this paper we outline some of the major communication phases needed in many PETSc codes and discuss how MPI is used to handle them.

Introduction Explicit parallel programming using the Message Passing Interface (MPI), a de facto standard created by the MPI Forum [15], is quickly becoming the strategy of choice for performance-portable parallel application programming on multicomputers and networks of workstations, so it is inevitably of interest to C++ programmers who use such systems. MPI programming is currently undertaken in C and/or Fortran-77, via the language bindings defined by the MPI Forum [15]. While the committee deferred the job of defining a C++ binding for MPI to MPI-2 [16], it is already possible to develop parallel programs in C++ using MPI, with the added help of one of several support libraries [2, 6, 13]. These systems all strive to enable immediate C++ programming based on MPI. The first such enabling system, MPI++, is the focus of this chapter. MPI++ was an early effort on our part to let us leverage MPI while programming in C++. Here this system is, to a large extent, our vehicle to i

This article describes the results of several numerical simulations of vortex dynamics in type-II superconductors. The underlying mathematical model is the time-dependent Ginzburg-Landau model. The simulations concern vortex penetration in the presence of twin boundaries, interface patterns between regions of opposite vortex orientation, and magnetic-flux entry patterns in superconducting samples. Numerical Simulation of Vortex Dynamics in Type-II Superconductors William D. Gropp, Hans G. Kaper, Gary K. Leaf, David M. Levine, Mario Palumbo, Valerii M. Vinokur 1 Ginzburg-Landau Model In this article we report on several numerical simulations of vortex motion in type-II superconducting materials [1,2]. The simulations are based on the time-dependent GinzburgLandau (TDGL) equations, ¯h 2 2m s D ` @ @t + i e s ¯h \Phi ' / = \Gamma ffi L ffi/ ; (1:1) oe c ` 1 c @A @t +r\Phi ' = \Gamma ffi L ffiA \Gamma 1 4ß r \Theta r \Theta A: (1:2) The symbol L stands for the ...

1 1 Introduction 2 1.1 Comments on Timings : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 6 2 Programming Packages and Tools 6 2.1 Graphical Display of System Use : : : : : : : : : : : : : : : : : : : : : : : : 6 2.2 Parallel Unix Tools : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 7 2.3 BlockSolve : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 8 2.4 Fortran M : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 8 2.5 Chameleon : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 9 2.6 Parallel Research on Invariant Subspace Methods : : : : : : : : : : : : : : : 10 2.7 MPI : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 12 2.8 PCN : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 12 2.9 Portable, Extensible Tools for Scientific Computing (PETSc) : : : : : : : : 13 2.10 p4 : : : : : : : : : : : : : : : : : : : : : : : : : : : ...

This paper presents a new kind of portability system, Unify, which modifies the PVM message passing system to provide (currrently a subset of) the Message Passing Interface (MPI) standard notation for message passing. Unify is designed to reduce the effort of learning MPI while providing a sensible means to make use of MPI libraries and MPI calls while applications continue to run in the PVM environment. We are convinced that this strategy will reduce the costs of porting completely to MPI, while providing a gradual environment within which to evolve. Furthermore, it will permit immediate use of MPI-based parallel libraries in applications, even those that use PVM for user code. We describe several paradigms for supporting MPI and PVM message passing notations in a single environment, and note related work on MPI and PVM implementations. We show the design options that existed within our chosen paradigm (which is an MPI interface added to the base PVM system), and why we chose that par...

The major contribution of this paper is the application of modern analysis techniques to the important Message Passing Interface standard, work done in order to obtain information useful in designing both application programmer interfaces for objectoriented languages, and message passing systems. Recognition of "Design Patterns" within MPI is an important discernment of this work. A further contribution is a comparative discussion of the design and evolution of three actual object-oriented designs for the Message Passing Interface (MPI-1) application programmer interface (API), two of which have influenced the standardization of C++ explicit parallel programming with MPI-2, and which strongly indicate the value of a priori object-oriented design and analysis of such APIs. Knowledge of design patterns is assumed herein. Discussion provided here includes systems developed at Mississippi State University (MPI++), the University of Notre Dame (OOMPI), and the merger of these sys...

The goal of this report is to survey state of the art and existing approaches for parallel programming on workstation clusters with special emphasis on object-oriented programming. First, workstation clusters as parallel computing platforms are characterized and fundamental concepts for parallel programming are discussed. Then, an overview of existing tools, systems, languages, and environments is given. The report concludes by identifying features of software systems suitable for parallel object-oriented programming on top of workstation clusters.

In this paper, we discuss the performance achieved by several implementations of the recently defined Message Passing Interface (MPI) standard. In particular, performance results for different implementations of the broadcast operation are analyzed and compared on the Delta, Paragon, SP1 and CM5. 1 Introduction For the past several years, members of the Parallel Research on Invariant Subspace Methods (PRISM) project have been investigating scalable parallel eigensolvers for distributed memory systems [1, 3]. The ultimate objective of this research is the development of portable and efficient libraries for this fundamental numerical linear algebra kernel. In the course of our work, we, like many other library developers, have been faced with many issues relating to portable programming. Previously, a notable obstacle to library development was the lack of standardization in message passing, from both a programming and a functional point of view. This lack of standardization made it dif...

v 1 Introduction 1 1.1 Getting Started : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 1 1.2 Usage Rules : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 1 1.3 SP1 Etiquette : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 2 1.4 Comments on This Manual : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 2 2 Machine Configuration 3 2.1 Hardware : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 3 2.2 Software : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 3 2.3 What Is Not Provided : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 4 3 Programming 5 3.1 Transport Layers : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 5 3.1.1 Ethernet/IP : : : : : : : : : : : : : : : : : : : : : : : ...