摘要:

AbstractThe aim of this paper is to show the use of MEC, an automated tool for analysing transition systems, for discovering deadlocks, livelocks and other properties of a given transition system. The features of MEC are shown with two instructive examples: first, the analysis of an electronic mail system, first analysed by G. Brebner using the concurrency work bench (another automated analysis tool); second, the analysis of a simple call‐processing system originating from Bell‐Northern‐Res

ISSN:0038-0644    

DOI:10.1002/spe.4380250602

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractIn many scientific applications, arrays containing data are indirectly indexed through indirection arrays. Such scientific applications are called irregular programs and are a distinct class of applications that require special techniques for parallelization.This paper presents a library called CHAOS, which helps users implement irregular programs on distributed‐memory message‐passing machines, such as the Paragon, Delta, CM‐5 and SP‐1. The CHAOS library provides efficient runtime primitives for distributing data and computation over processors; it supports efficient index translation mechanisms and provides users high‐level mechanisms for optimizing communication. CHAOS subsumes the previous PARTI library and supports a larger class of applications. In particular, it provides efficient support for parallelization of adaptive irregular programs where indirection arrays are modified during the course of computation. To demonstrate the efficacy of CHAOS, two challenging real‐life adaptive applications were parallelized using CHAOS primitives: a molecular dynamics code, CHARMM, and a particle‐in‐cell code, DSMC.Besides providing runtime support to users, CHAOS can also be used by compilers to automatically parallelize irregular applications. This paper demonstrates how CHAOS can be effectively used in such a framework. By embedding CHAOS primitives in the Syracuse Fortran 90D/HPF compiler, kernels taken from the CHARMM and DSMC codes have been automatical

ISSN:0038-0644    

DOI:10.1002/spe.4380250603

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractPARC++ is a system that supports object‐oriented parallel programming in C++. PARC++ provides the user with a set of predefined C++ classes that can easily be used for the construction of parallel C++ programs. With the help of PARC++ objects, the programmer is able to create and start new processes (threads), to synchronize their activities (Blocklock, Monitor) and to manage communication via message passing (Mailbox). PARC++ is written in C++ and currently runs on top of the EMEX operating system on a FORCE machine with 11 processing elements and an EDS (European Declarative System) with 28 processing elements. The paper also contains information about the run‐time system model, the implementation and some performance measureme

ISSN:0038-0644    

DOI:10.1002/spe.4380250604

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractWhen graphics input/output capabilities are added to a programming language originally designed with a text stream input/output model, various design decisions affect the ease with which the graphics facilities are learned and used by applications programmers. In adding window system facilities to the Icon programming language, some design decisions were made very differently from the conventional wisdom, resulting in substantial benefits for programmers. In addition, some pre‐existing Icon language features have proved to be useful in graphics programmin

ISSN:0038-0644    

DOI:10.1002/spe.4380250605

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractError recovery techniques for LR parsers presented in the literature are described and classified. The techniques considered range from the non‐correcting ones to interactive and incremental ones. Also, some of the techniques presented are compared and evaluated. An example showing the advantages and the disadvantages of each class of strategies is given and is used as a guideline for classifying syntax errors according to the recovery strategies which are more adequate to correct the

ISSN:0038-0644    

DOI:10.1002/spe.4380250606

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

摘要:

AbstractThis paper addresses the problem of monodimensional (1D) FFT parallel computation on constant‐valence multicomputers, i.e. on parallel systems made up of processing elements (PEs) which do not share memory and are connected to a bounded number of neighbours. After a qualitative analysis of several possible partitionings of the DIT FFT algorithm, a decomposition is introduced that has good scalability properties and makes it possible to use sections of sequential code based on the most common 1D‐FFT algorithms. If a computing architecture with indirect binaryn‐cube interconnection network is used, the proposed decomposition guarantees strictly local communications and therefore requires no through‐routing support. These characteristics have a positive impact on software development and also on overall performance. Furthermore, thanks to a pipelined organization of the PEs, the resulting architecture has high potentialities for real‐time signal processing. As these useful features are obtained at the ‘expense’ of an uneven workload distribution, computing efficiency is relatively low but does not significantly change in a wide range of the number of processors. An implementation on a Transputer‐based system is presented along with the performance results obtained. Finally a simple analytical model of the architecture is shown, that allows the values of the main performance parameters to be obtained as a function of the number of processors used and of the elementary response times of the fir

ISSN:0038-0644    

DOI:10.1002/spe.4380250607

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380250601

出版商:John Wiley&Sons, Ltd.    

年代:1995

数据来源: WILEY