基于运行时模型的混合云管理方法

随着云计算技术的普及,涌现出众多不同用途、不同类型的云计算平台.为了满足遗产系统整合和动态资源扩展等需求,常常需要构造混合云来统一管理不同云平台中的计算和存储资源.然而,不同云平台的管理接口和管理机制存在差异,使得开发混合云管理系统难度大、复杂度高.本文提出一种基于运行时模型的混合云管理方法：首先,在云平台管理接口基础上,构造单一云平台的运行时模型;其次,根据云平台领域知识,提出一种云平台软件体系结构的统一模型;最后,通过模型转换,实现云平台统一模型到运行时模型的映射.于是,管理程序可以建立在云平台统一模型的基础上,降低了混合云管理系统开发的难度和复杂度.本文还实现了基于运行时模型的CloudStack和亚马逊EC2混合云管理系统,并对方法的可行性和有效性进行了验证.     

主从式单边异构多核处理器编程模型和编译架构

主从式单边异构体系结构的异构多核处理器广泛应用于面向专门应用领域的计算加速,如异构多核嵌入式处理器、DSP、SoC等;高性能的该类处理器也可用于一些大规模科学和工程计算问题的处理。主从式单边异构处理器对编程模型和编译技术提出了很多挑战性问题,如编程模型的选择、编程语言的设计、编译器架构设计以及运行库的设计等。本文分析了这一类处理器结构特点和执行模型,认为功能卸载模型是最适用于这一体系结构的编程模型;并分析了面向功能卸载模型的编程语言设计关键问题,提出了编译系统的架构,讨论了相应的运行库设计问题。     

一种物流云系统的架构方法

为实现物流领域云服务,满足物流产业相关企业对云服务个性化,快速开发和多样化应用的需求,在云计算机应用架构的原理基础上,根据现代物流企业对物流云服务的特点,提出了一种集底层软硬件管理平台、云服务应用环境平台、云服务开发平台等为一体的物流云PaaS平台架构.讨论和分析了该架构的设计原理和实施细节,为进一步搭建物流领域多样化的SaaS应用提供了快速开发、统一协调和调度的平台,进而满足用户“一站式”个性化服务需求.     

基于Hadoop的校园云计算系统

针对传统的海量数据处理方法硬件成本太高,并行程序编写困难的缺点,在云计算理论的基础上设计了一个用于处理海量数据的校园云计算系统.此云计算系统是在Hadoop分布式计算框架的基础上采用Map-Reduce编程模型实现对海量数据的并行处理,有效解决了成本问题,降低了并行编程的难度.     

基于云计算虚拟化平台的安全基线配置核查研究

云计算是一个庞大的系统,其规模大小与复杂程度决定了解决云计算安全问题的难易程度。云平台的安全管控是科技、规章和行为的复杂组合。云计算环境的系统整体连通性和各级数据的完整性需综合考虑典型特征的网络、系统、应用和用户等诸多因素,将各解决方案相互联合、综合设计,才能保护云平台安全。本文将围绕云计算虚拟化平台,展开基于云计算虚拟化平台的安全基线配置及核查方法的研究,并由此设计云平台安全基线自动化核查技术。在此基础上,提出面向云平台组件安全基线配置的安全管控方法,旨在降低云计算虚拟化平台中各组件可能因配置不当所造成的安全风险,确保云平台系统安全、稳定地运行。     

OpenStack云计算平台高可用性的研究

随着云计算技术的不断发展,各种云计算平台也逐渐成熟,开源云平台OpenStack 也得到了各大IT 巨头的关 注和支持,发展迅速。本文论述了OpenStack 云平台的系统架构和系统的高可用性,着重描述了系统中实现高可用性采用的 两种模式：Active/Passive(主备模式)、Active/ Active（双活模式）。并对开放云平台OpenStack 中的各层次实现高可用性的实施 方案进行了剖析,为搭建OpenStack云平台时提高其可用性提供依据。     

一种面向PaaS的实例级应用动态更新技术

云计算是当前信息技术的重要技术领域,而平台即服务(PaaS)已成为业界研究的热点之一。PaaS平台为用户提供高可用、高可扩展的应用开发、部署和运行环境。然而当部署到云端的应用需要不断更新以修复错误、增加功能时,当前主流PaaS平台却因缺乏对应用在线更新的有效支持而削弱了其自身的高可用特性。为解决该问题,提出一个面向PaaS平台的动态更新技术框架。基于现有软件动态更新技术的研究,通过对PaaS平台中应用的事务管理、动态依赖管理、版本管理等机制的扩展,为PaaS平台提供运行时实例级的应用动态更新支撑,并在Cloud Foundry上进行实现和实验,结果证明了该动态更新技术的有效性。     

Parallel programming on a high‐performance application‐runtime

High‐performance application development remains challenging, particularly for scientists making the transition to a heterogeneous grid environment. In general areas of computing, virtual environments such as Java and .Net have proved to be successful in fostering application development, allowing users to target and compile to a single environment, rather than a range of platforms, instruction sets and libraries. However, existing runtime environments are focused on business and desktop computing and they do not support the necessary high‐performance computing (HPC) abstractions required by e‐Scientists. Our work is focused on developing an application‐runtime that can support these services natively. The result is a new approach to the development of an application‐runtime for HPC: the Motor system has been developed by integrating a high‐performance communication library directly within a virtual machine. The Motor message passing library is integrated alongside and in cooperation with other runtime libraries and services while retaining a strong message passing performance. As a result, the application developer is provided with a common environment for HPC application development. This environment supports both procedural languages, such as C, and modern object‐oriented languages, such as C#. This paper describes the unique Motor architecture, presents its implementation and demonstrates its performance and use. Copyright © 2008 John Wiley & Sons, Ltd.     

基于清华云监控平台的云迁移性能

当云计算技术兴起后,很多企业已经或计划将业务和应用迁移到云上,而这面临着应用性能可能降低,关键业务和应用安全性受到威胁等问题,因此是否云迁移还是部署到独立服务器上,是一个需要深入研究的问题.以清华云平台为基础,搭建了基于Nagios的清华云监控平台,先对清华云平台和架构进行介绍,再对Nagios和清华云监控平台架构进行了论述,在云迁移性能评估中,以Ubuntu和Windows为操作系统平台,以CPU负载和内存使用为评估指标,分别在云服务器和独立服务器上运行CPU运算类和服务器负载类两类应用,最后对实验结果进行了分析和比较.实验表明,部分应用在独立服务器上性能更好,并不适合云迁移.     

云计算研究现状与发展趋势

云计算是在网格计算的基础上发展而来的,是一种新兴的计算模型;介绍了云计算的定义和体系结构以及应用,从云平台的层次更深刻地剖析云计算的本质,对目前主流的云计算关键技术进行了详细介绍;最后讨论了云计算的热点问题,并指出了当前云计算系统亟待解决的问题与下一步的研究方向,可为云计算相关研究提供参考。     

机群OpenMP系统的设计与实现

OpenMP以其易用性和支持增量并行的特点成为共享存储体系结构的编程标准．目前机群系统已成为高性能计算的主流平台,研究机群OpenMP系统对推进并行应用的开发和普及非常有意义．该文作者以软件DSM系统JIAJIA作为OpenMP的运行时系统,结合一个前端编译器OMP2JIA,在机群系统上实现了OpenMP／JIAJIA计算环境,同时在提高性能方面根据机群系统特点扩展了OpenMP制导,优化了后端运行时库。通过11个OpenMP应用,作者比较了该计算环境和一个支持OpenMP的硬件cc-NUMA系统(SGI 2100)的性能．结果表明,作者的机群OpenMP系统的7机平均加速比为4．62;SGI 2100系统为4．55,二者性能相当．     

Integrating task parallelism in data parallel languages for parallel programming on NOWs

A number of high‐level parallel programming platforms for networks of workstations (NOWs) have been developed in recent times. Most of these platforms target the exploitation of data parallelism in applications. They do not allow expressibility of applications as a collection of tasks along with their precedence relationships. As a result, the control or task parallelism in an application cannot be expressed or exploited. The current work aims at integrating the notion of task parallelism and precedence relationships among constituting tasks to such high‐level data parallel platforms for NOWs. Our model of integration provides for arbitrary nesting of data and task parallel modules. Also, the precedence relationships are clearly reflected from the program structure. The model relieves the programmer from the need to design applications for non‐determinism in the order of completion of constituting tasks. The design of the runtime support as well as system‐level book keeping is discussed. The model is general enough to be applied to a wide range of data parallel platforms. A specific case of integrating the model into anonymous remote computing (ARC), a data parallel programming platform, is presented. The performance related aspects are also discussed. Copyright © 2000 John Wiley & Sons, Ltd.     

Dynamic cloud resource management for efficient media applications in mobile computing environments

Single-instruction-set architecture (Single-ISA) heterogeneous multi-core processors (HMP) are superior to Symmetric Multi-core processors in performance per watt. They are popular in many aspects of the Internet of Things, including mobile multimedia cloud computing platforms. One Single-ISA HMP integrates both fast out-of-order cores and slow simpler cores, while all cores are sharing the same ISA. The quality of service (QoS) is most important for virtual machine (VM) resource management in multimedia mobile computing, particularly in Single-ISA heterogeneous multi-core cloud computing platforms. Therefore, in this paper, we propose a dynamic cloud resource management (DCRM) policy to improve the QoS in multimedia mobile computing. DCRM dynamically and optimally partitions shared resources according to service or application requirements. Moreover, DCRM combines resource-aware VM allocation to maximize the effectiveness of the heterogeneous multi-core cloud platform. The basic idea for this performance improvement is to balance the shared resource allocations with these resources requirements. The experimental results show that DCRM behaves better in both response time and QoS, thus proving that DCRM is good at shared resource management in mobile media cloud computing.     

面向云计算的粒度自配置日志采集平台

日志数据管理系统是最重要的云服务基础设施之一。重要日志数据缺失将造成相应日志分析与决策的片面性和不准确性。然而日志数据采集能力越强,日志采集的运行期开销就越大,海量日志数据的管理与分析就越耗时,对整个云服务环境的系统性能造成不可忽视的影响。针对如何采集必要的日志数据同时尽可能降低其运行期开销的问题,文章首先提出日志采集粒度的概念,然后设计并编程实现一个面向云计算的粒度自配置日志采集平台。其中,平台构成模块包括:日志采集工具、存储日志采集粒度规则和事实的知识库;基于规则动态增加或关闭相关日志数据采集模块的推理机;相应的图形界面,包括用于添加或修改知识库规则的管理界面和直观查看日志数据的用户界面。最后,初步的案例学习结果表明了平台的有效性。     

Mayfly: A general-purpose, scalable, parallel processing architecture

TheMayfly is a scalable general-purpose parallel processing system being designed at HP Laboratories, in collaboration with colleagues at the University of Utah. The system is intended to efficiently support parallel variants of modern programming languages such as Lisp, Prolog, and Object Oriented Programming models. These languages impose a common requirement on the hardware platform to supportdynamic system needs such as runtime type checking and dynamic storage management. The main programming language for the Mayfly is a concurrent dialect of Scheme. The system is based on a distributed-memory model, and communication between processing elements is supported by message passing. The initial prototype of Mayfly will consist of 19 identical processing elements interconnected in a hexagonal mesh structure. In order to achieve the goal of scalable performance, each processing element is a parallel processor as well, which permits the application code, runtime operating system, and communication to all run in parallel. A 7 processing element subset of the prototype is presently operational. This paper describes the hardware architecture after a brief background synopsis of the software system structure.     

A dependable Peer-to-Peer computing platform

This paper discusses a dependable and widely applicable Peer-to-Peer (P2P) computing platform. As the existing P2P computing platforms are limited due to the lack of support for various computational models, this paper proposes a workflow management mechanism to support task dependency in parallel programs while increasing computing efficiency. In general, task dependency leads to a serious performance degradation for failed task re-execution because of volatile peers. Therefore, it results in low dependability. Here, dependability is defined as a comparison of the actual performance with task failures to the theoretical one without failure on a P2P computing platform. Redundant task dispatch and a runtime optimization method are proposed to guarantee high dependability even with highly volatile peers. Large-scale simulation results indicate that the computing platform efficiently solves the problem of P2P computing due to volatile peers.     

Model Architecture for Cloud Computing-Based Library Management

The purpose of this article is to provide a cloud computing system-based architecture for library automation services. In this article, a consortium-based library automation system has been conceptualized and a model architecture has been proposed. The article describes the benefit of virtualization (Virtual Machine as a library) of cloud computing toward libraries and why/how a librarian can shift from an on-premise based library system to cloud-based system to overcome infrastructure requirement, staff requirements for administration, system maintenance, costs for backup, and so forth. The article outlines the traditional system of library automation. The proposed model provides cloud platform and application virtualization solutions for deploying and managing Service Oriented Architecture (SOA) for libraries. The model illustrates how a group of libraries, participating into a consortia, could collaborately obtain access to LMS software application through the virtual platform. This article is one of the first of its kind to propose such architecture for library automation.     

基于KVM的虚拟桌面基础架构设计与优化

随着云计算的不断发展,虚拟桌面基础架构(Virtual Desktop Infrastructure,VDI)解决方案日益成熟。VDI建立在虚拟化技术的基础上,突破了时间和空间的限制,有效地解决了传统个人计算机使用过程中存在的诸多问题,是当前桌面云解决方案中主流的架构与部署方式。充分利用VDI的优势,结合目前流行的KVM虚拟化技术,探讨解析虚拟桌面架构并进行实际部署,详细设计了平台优化方案,最后进行了测试并记录了性能表现,验证了系统的正确性和可用性。结果表明,VDI为现代机房带来了移动计算、方便管理和降低运维成本等诸多改进,为高校实际安装部署虚拟化平台提供了现实的指导意义。     

A hybrid class- and prototype-based object model to support language-neutral structural intercession

ContextDynamic languages have turned out to be suitable for developing specific applications where runtime adaptability is an important issue. Although .Net and Java platforms have gradually incorporated features to improve their support of dynamic languages, they do not provide intercession for every object or class. This limitation is mainly caused by the rigid class-based object model these platforms implement, in contrast to the flexible prototype-based model used by most dynamic languages.ObjectiveOur approach is to provide intercession for any object or class by defining a hybrid class- and prototype-based object model that efficiently incorporates structural intercession into the object model implemented by the widespread .Net and Java platforms.MethodIn a previous work, we developed and evaluated an extension of a shared-source implementation of the .Net platform. In this work, we define the formal semantics of the proposed reflective model, and modify the existing implementation to include the hybrid model. Finally, we assess its runtime performance and memory consumption, comparing it to existing approaches.ResultsOur platform shows a competitive runtime performance compared to 9 widespread systems. On average, it performs 73% and 61% better than the second fastest system for short- and long-running applications, respectively. Besides, it is the JIT-compiler approach that consumes less average memory. The proposed approach of including a hybrid object-model into the virtual machine involves a 444% performance improvement (and 65% less memory consumption) compared to the existing alternative of creating an extra software layer (the DLR). When none of the new features are used, our platform requires 12% more execution time and 13% more memory than the original .Net implementation.ConclusionOur proposed hybrid class- and prototype-based object model supports structural intercession for any object or class. It can be included in existing JIT-compiler class-based platforms to support common dynamic languages, providing competitive runtime performance and low memory consumption.     

Providing Source Code Level Portability Between CPU and GPU with MapCG

Graphics processing units (GPU) have taken an important role in the general purpose computing market in recent years.At present,the common approach to programming GPU units is to write GPU specific cod...