97 research outputs found

    Performance impact of the grid middleware

    Get PDF
    The Open Grid Services Architecture (OGSA) defines a new vision of the Grid based on the use of Web Services (Grid Services). The standard interfaces, behaviors and schemes that are consistent with the OGSA specification are defined by the Open Grid Service Infrastructure (OGSI). Grid Services, as an extension of the Web Services, run on top of rich execution frameworks that make them accessible and interoperable with other applications. Two examples of these frameworks are Sun’s J2EE platform and Microsoft’s .NET. The Globus Project implements the OGSI Specification for the J2EE framework in the Globus Toolkit. As any J2EE application, the performance of the Globus Toolkit is constrained by the performance obtained by the J2EE execution stack This performance can be influenced by many points of the execution stack: operating system, JVM, middleware or the same grid service, without forgetting the processing overheads related to the parsing of the communication protocols. In the scope of this chapter, all this levels together will be referred to as the grid middleware. In order to avoid the grid middleware to become a performance bottleneck for a distributed grid-enabled application, grid nodes have to be tuned for an efficient execution of I/O intensive applications because they can receive a high volume of requests every second and have to deal with a big amount of invocations, message parsing operations and a continuous task of marshaling and unmarshalling service parameters. All the parameters of the system affecting these operations have to be tuned according with the expected system load intensity. A Grid node is connected to to other nodes through a network connection which is also a decisive factor to obtain a high performance for a grid application. If the inter-node data transmission time overlaps completely the processing time for a computational task, the benefits of the grid architecture will be lost. Additionally, in many situations the content exchanged between grid nodes can be considered confidential and should be protected from curious sights. But the cost of data encryption/decryption can be an important performance weak that must be taken into account. In this chapter we will study the process of receiving and executing a Grid job from the perspective of the underlying levels existing below the Grid application. We will analyze the different performance parameters that can influence in the performance of the Grid middleware and will show the general schema of tasks involved in the service of an execution request.Postprint (author’s final draft

    High Availability and Scalability of Mainframe Environments using System z and z/OS as example

    Get PDF
    Mainframe computers are the backbone of industrial and commercial computing, hosting the most relevant and critical data of businesses. One of the most important mainframe environments is IBM System z with the operating system z/OS. This book introduces mainframe technology of System z and z/OS with respect to high availability and scalability. It highlights their presence on different levels within the hardware and software stack to satisfy the needs for large IT organizations

    Mining Crosscutting Concerns through Random Walks

    Full text link

    Web services strategy

    Get PDF
    Thesis (S.M.M.O.T.)--Massachusetts Institute of Technology, Sloan School of Management, Management of Technology Program, 2003.June 2003.Includes bibliographical references (p. 116-123).This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Everything is connected to everything. El Aleph (1945), by Jorge Luis Borges[1] This thesis addresses the need to simplify and streamline web service network infrastructure and to identify business models that best leverage Web services technology and industry dynamics to generate positive business results. Web services have evolved from the simple page-display protocol of their origin and now reach beyond the links that simply updated web data dynamically from corporate databases, to where systems can automatically transact. These Web services represent a series of network business technology standards and capabilities that irrevocably change the way in which businesses will do business. In fact, every business today is a networked business and has opportunities to grow using Web services. This study focuses on the implementation challenges in the financial services market, specifically the On Line Transaction Processing (OLTP) sector where legacy mainframes interface with multiple tiers of distribution through proprietary EDI links. The OLTP industry operates under stringent regulatory requirements for availability and audit-ability of not only who performed what transaction, but who had access to the information about the information. In this environment organizational demands on network infrastructure including hardware, software and personnel are changing radically, while concurrently Information Technology (IT) budgets are under pressure. The strategic choices for deploying web services in this environment may contain lessons for other industries where cost effective large scale processing, high availability, security, manageability and Intellectual Property Rights (IPR) are paramount concerns. In this paper we use a systems dynamics model to simulate the impact of market changes on the adoption of innovative technologies and their commoditization on the industry value chain, with the aim of identifying business models and network topologies which best support the growth of an Open Systems network business. From the results of the simulation we will derive strategic recommendations for networked business models and web services integration strategies to meet Line Of Business (LOB) objectives.by Stephen B. Miles.S.M.M.O.T

    EinfĂĽhrung in z/OS

    Get PDF

    A Scalable Cluster-based Infrastructure for Edge-computing Services

    Get PDF
    In this paper we present a scalable and dynamic intermediary infrastruc- ture, SEcS (acronym of BScalable Edge computing Services’’), for developing and deploying advanced Edge computing services, by using a cluster of heterogeneous machines. Our goal is to address the challenges of the next-generation Internet services: scalability, high availability, fault-tolerance and robustness, as well as programmability and quick prototyping. The system is written in Java and is based on IBM’s Web Based Intermediaries (WBI) [71] developed at IBM Almaden Research Center

    Dynamic deployment of specialized ESB instances in the cloud

    Get PDF
    In the last years the interaction among heterogeneous applications within one or among multiple enterprises has considerably increased. This fact has arisen several challenges related to how to enable the interaction among enterprises in an interoperable manner. Towards addressing this problem, the Enterprise Service Bus (ESB) has been proposed as an integration middleware capable of wiring all the components of an enterprise system in a transparent and interoperable manner. Enterprise Service Buses are nowadays used to transparently establish and handle interactions among the components within an application or with consumed external services. There are several ESB solutions available in the market as a result of continuously developing message-based approaches aiming at enabling interoperability among enterprise applications. However, the configuration of an ESB is typically custom, and complex. Moreover, there is little support and guidance for developers related to how to efficiently customize and configure the ESB with respect to their application requirements. Consequently, this fact also increments notably the maintenance and operational costs for enterprises. Our target is mainly to simplify the configuration tasks at the same time as provisioning customized ESB instances to satisfy the application's functional and non-functional requirements. Similar works focus on optimizing existing ESB configurations based on runtime reconfiguration rather than offering customized light-weight middleware components. This Master thesis aims at providing the means to build customized and specialized ESB instances following a reusable and light-weight approach. We propose the creation of a framework capable of guiding the application developer in the tasks related to configuring, provisioning, and executing specialized ESB instances in an automatic, dynamic, and reusable manner. Specialized ESB instances are created automatically and provided to application developers that can build an ESB instance with a specific configuration which may change over time. The proposed framework also incorporates the necessary support for administering, provisioning, and maintaining a clustered infrastructure hosting the specialized ESB instances in an isolated manner

    Taguchi approach for performance evaluation of service-oriented software systems.

    Get PDF
    Service-oriented software systems are becoming increasingly common in the world today as big companies such as Microsoft and IBM advocate approaches focusing on assembly of system from distributed services. Although performance of such systems is a big problem, there is surprisingly an obvious lack of attention for evaluating the performance of enterprise-scale, service-oriented software systems. This thesis investigates the application of statistical tools in performance engineering domain for total quality management. In particular, the Taguchi approach is used as an efficient and systematic way to optimize designs for performance, quality, and cost. The aim is to improve the performance of software systems and to reduce application development cost by assembling services from known vendors or intranet services. The focus of this thesis is on the response time of service-oriented systems. Nevertheless, the developed methodology also applies to other performance issues, such as memory management and caching. The interaction problems of those issues are preserved for future work.Dept. of Computer Science. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2004 .L585. Source: Masters Abstracts International, Volume: 43-01, page: 0240. Adviser: Xiaobu Yuan. Thesis (M.Sc.)--University of Windsor (Canada), 2004

    QoS control of E-business systems through performance modelling and estimation

    Get PDF
    E-business systems provide the infrastructure whereby parties interact electronically via business transactions. At peak loads, these systems are susceptible to large volumes of transactions and concurrent users and yet they are expected to maintain adequate performance levels. Over provisioning is an expensive solution. A good alternative is the adaptation of the system, managing and controlling its resources. We address these concerns by presenting a model that allows fast evaluation of performance metrics in terms of measurable or controllable parameters. The model can be used in order to (a) predict the performance of a system under given or assumed loading conditions and (b) to choose the optimal configuration set-up for certain controllable parameters with respect to specified performance measures. Firstly, we analyze the characteristics of E-business systems. This analysis leads to the analytical model, which is sufficiently general to capture the behaviour of a large class of commonly encountered architectures. We propose an approximate solution which is numerically efficient and fast. By mean of simulation, we prove that its accuracy is acceptable over a wide range of system configurations and different load levels. We further evaluate the approximate solution by comparing it to a real-life E-business system. A J2EE application of non-trivial size and complexity is deployed on a 2-tier system composed of the JBoss application server and a database server. We implement an infrastructure fully integrated on the application server, capable of monitoring the E-business system and controlling its configuration parameters. Finally, we use this infrastructure to quantify both the static parameters of the model and the observed performance. The latter are then compared with the metrics predicted by the model, showing that the approximate solution is almost exact in predicting performance and that it assesses the optimal system configuration very accurately.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Analysis of requirements and technologies to migrate software development to the PaaS model

    Get PDF
    Dissertation presented as the partial requirement for obtaining a Master's degree in Information Management, specialization in Information Systems and Technologies ManagementSoftware development has been evolving during the last years and, more and more, the software architecture to support this development has become more complex to meet the new requirements and new technologies. With the new cloud computing architecture and models, IT departments and ISV are developing new applications and moving the traditional software architecture to the cloud. In this context, Platform as a Service (PaaS) model can provide software development services and components within a new architecture for building a new generation of software with all benefits of cloud, like scalability and elasticity. However, currently, most companies have significant challenges to adapt and change its software development process to use the PaaS architecture and the cloud services. In this dissertation, it will first be identified and analyzed the changes and challenges for develop software with the PaaS architecture. Afterwards, will be analyzed and identified the requirements in a traditional software development and architecture (on premise) to development new software or adapt the existents software with the PaaS.Dissertation submitted as partial requirement for obtaining the Master’s degree in Information Managemen
    • …
    corecore