29,877 research outputs found

    A Distributed Parallel Processing Environment Based upon the Linda Paradigm: A Research Prospectus

    Get PDF
    As the computing capacity of the uniprocessor is being taxed, and the high cost of parallel and super-computers is still prevalent, alternative methods of achieving parallel performance at an economical price are desired. This proposed research effort offers one such alternative, focusing on the idle CPU cycles existing on local area networks. With the increase in the computing power of workstations and their declining costs, one can effectively transform the unused computing power attached to a local area network into a parallel processing environment. Effectively exploiting such an environment, however, requires a specification and operational framework that is portable, easy to use, and efficient. The environment is constructed around the Linda parallel programming paradigm which provides an effective parallel computational framework

    Parallel processing for scientific computations

    Get PDF
    The scope of this project dealt with the investigation of the requirements to support distributed computing of scientific computations over a cluster of cooperative workstations. Various experiments on computations for the solution of simultaneous linear equations were performed in the early phase of the project to gain experience in the general nature and requirements of scientific applications. A specification of a distributed integrated computing environment, DICE, based on a distributed shared memory communication paradigm has been developed and evaluated. The distributed shared memory model facilitates porting existing parallel algorithms that have been designed for shared memory multiprocessor systems to the new environment. The potential of this new environment is to provide supercomputing capability through the utilization of the aggregate power of workstations cooperating in a cluster interconnected via a local area network. Workstations, generally, do not have the computing power to tackle complex scientific applications, making them primarily useful for visualization, data reduction, and filtering as far as complex scientific applications are concerned. There is a tremendous amount of computing power that is left unused in a network of workstations. Very often a workstation is simply sitting idle on a desk. A set of tools can be developed to take advantage of this potential computing power to create a platform suitable for large scientific computations. The integration of several workstations into a logical cluster of distributed, cooperative, computing stations presents an alternative to shared memory multiprocessor systems. In this project we designed and evaluated such a system

    File Access Performance of Diskless Workstations

    Get PDF
    This paper studies the performance of single-user workstations that access files remotely over a local area network. From the environmental, economic, and administrative points of view, workstations that are diskless or that have limited secondary storage are desirable at the present time. Even with changing technology, access to shared data will continue to be important. It is likely that some performance penalty must be paid for remote rather than local file access. Our objectives are to assess this penalty and to explore a number of design alternatives that can serve to minimize it. Our approach is to use the results of measurement experiments to parameterize queuing network performance models. These models then are used to assess performance under load and to evahrate design alternatives. The major conclusions of our study are: (1) A system of diskless workstations with a shared file server can have satisfactory performance. By this, we mean performance comparable to that of a local disk in the lightly loaded case, and the ability to support substantial numbers of client workstations without significant degradation. As with any shared facility, good design is necessary to minimize queuing delays under high load. (2) The key to efficiency is protocols that allow volume transfers at every interface (e.g., between client and server, and between disk and memory at the server) and at every level (e.g., between client and server at the level of logical request/response and at the level of local area network packet size). However, the benefits of volume transfers are limited to moderate sizes (8-16 kbytes) by several factors. (3) From a performance point of view, augmenting the capabilities of the shared file server may be more cost effective than augmenting the capabilities of the client workstations. (4) Network contention should not be a performance problem for a lo-Mbit network and 100 active workstations in a software development environment

    Issues in ATM Support of High-Performance, Geographically Distributed Computing

    Get PDF
    This report experimentally assesses the effect of the underlying network in a cluster-based computing environment. The assessment is quantified by application-level benchmarking, process-level communication, and network file input/output. Two testbeds were considered, one small cluster of Sun workstations and another large cluster composed of 32 high-end IBM RS/6000 platforms. The clusters had Ethernet, fiber distributed data interface (FDDI), Fibre Channel, and asynchronous transfer mode (ATM) network interface cards installed, providing the same processors and operating system for the entire suite of experiments. The primary goal of this report is to assess the suitability of an ATM-based, local-area network to support interprocess communication and remote file input/output systems for distributed computing

    Public Libraries and the Internet 2006

    Get PDF
    Examines the capability of public libraries to provide and sustain public access Internet services and resources that meet community needs, including serving as the first choice for content, resources, services, and technology infrastructure

    The role of the host in a cooperating mainframe and workstation environment, volumes 1 and 2

    Get PDF
    In recent years, advancements made in computer systems have prompted a move from centralized computing based on timesharing a large mainframe computer to distributed computing based on a connected set of engineering workstations. A major factor in this advancement is the increased performance and lower cost of engineering workstations. The shift to distributed computing from centralized computing has led to challenges associated with the residency of application programs within the system. In a combined system of multiple engineering workstations attached to a mainframe host, the question arises as to how does a system designer assign applications between the larger mainframe host and the smaller, yet powerful, workstation. The concepts related to real time data processing are analyzed and systems are displayed which use a host mainframe and a number of engineering workstations interconnected by a local area network. In most cases, distributed systems can be classified as having a single function or multiple functions and as executing programs in real time or nonreal time. In a system of multiple computers, the degree of autonomy of the computers is important; a system with one master control computer generally differs in reliability, performance, and complexity from a system in which all computers share the control. This research is concerned with generating general criteria principles for software residency decisions (host or workstation) for a diverse yet coupled group of users (the clustered workstations) which may need the use of a shared resource (the mainframe) to perform their functions

    Windows .NET Network Distributed Basic Local Alignment Search Toolkit (W.ND-BLAST)

    Get PDF
    BACKGROUND: BLAST is one of the most common and useful tools for Genetic Research. This paper describes a software application we have termed Windows .NET Distributed Basic Local Alignment Search Toolkit (W.ND-BLAST), which enhances the BLAST utility by improving usability, fault recovery, and scalability in a Windows desktop environment. Our goal was to develop an easy to use, fault tolerant, high-throughput BLAST solution that incorporates a comprehensive BLAST result viewer with curation and annotation functionality. RESULTS: W.ND-BLAST is a comprehensive Windows-based software toolkit that targets researchers, including those with minimal computer skills, and provides the ability increase the performance of BLAST by distributing BLAST queries to any number of Windows based machines across local area networks (LAN). W.ND-BLAST provides intuitive Graphic User Interfaces (GUI) for BLAST database creation, BLAST execution, BLAST output evaluation and BLAST result exportation. This software also provides several layers of fault tolerance and fault recovery to prevent loss of data if nodes or master machines fail. This paper lays out the functionality of W.ND-BLAST. W.ND-BLAST displays close to 100% performance efficiency when distributing tasks to 12 remote computers of the same performance class. A high throughput BLAST job which took 662.68 minutes (11 hours) on one average machine was completed in 44.97 minutes when distributed to 17 nodes, which included lower performance class machines. Finally, there is a comprehensive high-throughput BLAST Output Viewer (BOV) and Annotation Engine components, which provides comprehensive exportation of BLAST hits to text files, annotated fasta files, tables, or association files. CONCLUSION: W.ND-BLAST provides an interactive tool that allows scientists to easily utilizing their available computing resources for high throughput and comprehensive sequence analyses. The install package for W.ND-BLAST is freely downloadable from . With registration the software is free, installation, networking, and usage instructions are provided as well as a support forum
    corecore