可扩展网格文件访问接口的设计与实现

描述了网格文件访问接口(GFAI)的设计和实现。GFAI实现了一个与POSIX标准兼容的、可扩展的网格文件访问接口，屏蔽了不同存储系统访问协议的细节，解决了不同网格文件访问/传输协议的异构性问题，为用户提供了一个统一的、易于使用的网格I/O接口。     

消息传递机制的比较及其最新发展

消息传递机制在分布式计算中发挥着很重要的作用.随着人们对高性能计算需求的不断扩大和各种新技术的出现,消息传递机制也处于不断的发展和完善之中.首先对两种主要的消息传递系统PvM和MPI进行了详尽的比较,比如背景、目标、移植性、通信等;然后针对它们的现状列举了最新发展情况;最后归纳了消息传递机制的发展趋势.     

基于网格计算市场模型的资源与作业描述语言的研究

网格计算市场模型是把经济学的概念应用到网格的资源管理和作业调度中的模型。本文分析了网格计算市场模型中资源和作业描述语言的需求,简要介绍了资源和作业描述语言Classified Advertisements(Classad),指出它在网格计算市场模型中描述资源和作业的不足之处,对它做了相应的改进和扩充．以实现在经济模型下对资源和作业更加灵活、细枉度的描述。     

基于Web的网格系统的实现

介绍了一种基于Web的网格系统的实现，并阐述了网格中使用的关键技术，提出了网格资源分级管理与全局调度的思想。     

基于GT2和MPICH-G2计算网格平台的设计

针对某些科学研究领域计算方法复杂、数据量庞大的问题,设计和构建了一个基于Globus的计算网格环境,能够发现可用计算节点,并动态提交计算任务。同时,Globus工具包2为构建网格环境和网格应用提供了可以直接调用的API函数接口,提高了并行计算的效率。通过运行一个典型的并行算法,验证了平台的可用性和高效性,并进行了结果分析。     

基于JSF的网格门户设计与实现

网格门户在推广网格应用中起了重要作用,但网格门户在诸多方面如功能和表现能力等仍有待完善.引入JavaServerFaces （JSF）这一新的Web框架,设计和实现了一个网格门户.利用JSF的表现能力提供了一个更为丰富的、集成的、易操作并且可定制的用户接口.并且由于JSF与其它Java技术、底层的网格技术实现无缝的衔接,实现了平台无关的、强大的网格资源管理及动态配置功能,同时使系统具有更强的可扩展性.     

基于Globus平台的网格服务实现

网格是一个集成的计算与资源环境，或者说是一个计算资源池。网格能够充分吸纳各种计算资源，并将它们转化为一种随处可得的、可靠的、标准的、经济的计算能力。网格这个概念来源于电力网格（Electric Power Grid），它的最终目的是希望用户在使用网格计算能力时，如同使用电力那样方便。     

MPICH-G2及其在网格计算中的应用研究

介绍了MPI与网格计算的相关概念,描述了MPICH-G2的工作原理、特性以及MPICH-G2在网格环境下实现MPI并行计算的方法.综合阐述了MPICH-G2的通信性能及其在网格计算中的应用现状,并且通过对近几年使用MPlCH-G2和Globus网格服务结合搭建分布式异构环境的典型实例的具体分析,展示了MPICH-G2在网格计算中的重要作用,总结了MPICH-G2的现存问题与发展前景.     

一种新和消息传递型处理机系统中总线接口的设计

多处理机系统分为共享存储器型和消息传递型。本文提出了一种新的消息传递型多处理机系统的总线接口的设计方法。区别于以往的总线接口的方法，引入了口的概念。优点是使得接收方也有权决定信息包接收与否，算法更灵活，可用广播传送方式，还可以动态地进行了进程转移。     

基于网格的分布式数据挖掘

针对分布式数据挖掘和网格计算的特点,本文详细分析了目前主流的几种网格体系结构,设计了一种基于开放网格服务架构的Web服务资源框架的分布式数据挖掘整体架构,通过应用描述了它们的具体数据挖掘流程。应用结果验证了该架构在网格环境下进行分布式数据挖掘的可行性和高效性。     

基于消息传递的数据交错重分布负载平衡技术

数据重分布是实现消息传递环境下负载平衡的重要手段,提出了数据交错分布的模型问题及模型问题的并行计算模型,分析了模型问题在消息传递环境下的实现,讨论了性能和适用条件,给出了分析结果,讨论了通信与计算的时间重叠问题,将数据交错重分布负载平衡技术应用到非平衡刚性动力学方程组的并行计算中,获得了很好的负载平衡效果。     

基于JMS规范的消息系统可靠性保障对策

为实现机场管理信息系统（AMIS）中各业务子系统之间互操作和无缝连接,基于JMS规范的消息系统首先需要解决的就是消息可靠性问题,在针对JMS规范的两种消息传递模型,结合机场消息中事件固有的先后顺序关系,提出了一种更高效更适合机场业务的保障消息可靠性的方法,并给予了实现。     

Transformations for early reply and forward message passing mechanisms

Message passing notations (language, package, etc.) typically include some form of asynchronous or synchronous invocation. In a synchronous invocation, the invoker waits for the invocation's servicer to pass back results. Some message passing notations also include early reply or deferred reply (including forwarding), which alters how and when the servicer passes back its results; this additional flexibility is useful in realistic applications. It is well known how to transform a synchronous invocation into only asynchronous invocations. This paper extends such transformations to early reply and forward. This paper also describes the use of these transformations within the implementations of programming notations. Using the transformation simplifies the implementation without significantly affecting run‐time costs. Copyright © 2015 John Wiley & Sons, Ltd.     

基于请求应答方式消息传递机制有色Petri网模型

分布式系统的对等模型中,各个节点从功能上看是对等关系,相互之间进行消息的请求和响应。讨论了一种将广播请求和点到点应答两种通信方式相结合的消息传递机制FMPRR(Fast Message Passing based on Request Response mode)的实现,这种机制采用wormhole寻径流控策略。用有色Petri网来形式化描述和分析FMPRR,通过模型状态空间分析结果,对FMPRR消息传递机制进行验证。     

基于压缩感知的期望最大化贝努利非对称高斯近似信息传递算法

期望最大化贝努利高斯(BG)近似信息传递(EM-BG-AMP)算法中的BG模型因为具有对称性,在逼近实际信号先验分布时会受到限制;而期望最大化高斯混合近似信息传递(EM-GM-AMP)算法中的GM模型是BG模型的高阶形式,复杂度较高。为了解决以上问题,提出贝努利不对称高斯模型(BAG),进而推导得到期望最大化贝努利不对称高斯近似信息传递(EM-BAG-AMP)算法。该算法的主要思路是假设输入信号服从BAG模型,然后使用广义近似信息传递(GAMP)重构信号并在算法迭代中同时更新模型参数。实验证明,在处理不同图像数据时,EM-BAG-AMP和EM-BG-AMP相比,时间增加了1.2%,峰值信噪比(PSNR)值提升了0.1~0.5 dB,尤其在处理纹理较少以及色差变化明显的图像时峰值信噪比(PSNR)值提升了0.4~0.5 dB。EM-BAG-AMP是对EM-BG-AMP算法的扩展和延伸,更适合实际信号的处理。     

Efficient communication using message prediction for clusters of multiprocessors

With the increasing uniprocessor and symmetric multiprocessor computational power available today, interprocessor communication has become an important factor that limits the performance of clusters of workstations/multiprocessors. Many factors including communication hardware overhead, communication software overhead, and the user environment overhead (multithreading, multiuser) affect the performance of the communication subsystems in such systems. A significant portion of the software communication overhead belongs to a number of message copying operations. Ideally, it is desirable to have a true zero‐copy protocol where the message is moved directly from the send buffer in its user space to the receive buffer in the destination without any intermediate buffering. However, due to the fact that message‐passing applications at the send side do not know the final receive buffer addresses, early arrival messages have to be buffered at a temporary area. In this paper, we show that there is a message reception communication locality in message‐passing applications. We have utilized this communication locality and devised different message predictors at the receiver sides of communications. In essence, these message predictors can be efficiently used to drain the network and cache the incoming messages even if the corresponding receive calls have not yet been posted. The performance of these predictors, in terms of hit ratio, on some parallel applications are quite promising and suggest that prediction has the potential to eliminate most of the remaining message copies. We also show that the proposed predictors do not have sensitivity to the starting message reception call, and that they perform better than (or at least equal to) our previously proposed predictors. Copyright © 2002 John Wiley & Sons, Ltd.     

基于MPI的Welch功率谱估计并行算法的实现

Welch算法是一种应用很广的经典功率谱估计算法。但是面对现在日益膨胀的海量数据,单纯在串行Matlab环境下运行Welch算法势必耗费大量的运算时间。尽管Matlab也引入了并行计算工具箱,但是价格昂贵,不利于大范围推广使用。根据Welch算法的原理,在Linux集群环境及消息传递接口MPI 的支持下,采用主从并行编程模式,实现了一个开源的Welch并行算法PMWelch。实验结果表明,PMWelch不仅具有Matlab下Welch算法一样的运算结果,还可以大幅减少运行时间。     

Sigiri: uniform resource abstraction for grids and clouds

With the maturation of grid computing facilities and recent explosion of cloud computing data centers, midscale computational science has more options than ever before to satisfy computational needs. But heterogeneity brings complexity. We propose a simple abstraction for interaction with heterogeneous resource managers spanning grid and cloud computing and on features that make the tool useful for the midscale physical or natural scientist. Key strengths of the abstraction are its support for multiple standard job specification languages, preservation of direct user interaction with the service, removing the delay that can come through layers of services, and the predictable behavior under heavy loads. Copyright © 2012 John Wiley & Sons, Ltd.     

Energy efficient and robust allocation of interdependent tasks on mobile ad hoc computational grid

A mobile ad hoc computational grid is a distributed computing infrastructure that allows mobile nodes to share computing resources in a mobile ad hoc environment. Compared to traditional distributed systems such as grids and clouds, resource allocation in mobile ad hoc computational grids is not straightforward because of node mobility, limited battery power and an infrastructure‐less network environment. The existing schemes are either based on a decentralized architecture that results in poor allocation decisions or assume independent tasks. This paper presents a scheme that allocates interdependent tasks and aims to reduce task completion time and the amount of energy consumed in transmission of data. This scheme comprises two key algorithms: resource selection and resource allocation. The resource selection algorithm is designed to select nodes that remain connected for a longer period, whereas the resource assignment or allocation algorithm is developed to allocate interdependent tasks to the nodes that are accessible at the minimum transmission power. The scheme is based on a hybrid architecture that results in effective allocation decisions, reduces the communication cost associated with the exchange of control information, and distributes the processing burden among the nodes. The paper also investigates the relationship between the data transfer time and transmission energy consumption and presents a power‐based routing protocol to reduce data transfer costs and transmission energy consumption. Copyright © 2014 John Wiley & Sons, Ltd.