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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Monitoring and Optimization of ATLAS Tier 2 Center GoeGrid

Magradze, Erekle 11 January 2016 (has links)
No description available.
52

A framework for evolving grid computing systems

Alfawair, Mai January 2009 (has links)
Grid computing was born in the 1990s, when researchers were looking for a way to share expensive computing resources and experiment equipment. Grid computing is becoming increasingly popular because it promotes the sharing of distributed resources that may be heterogeneous in nature, and it enables scientists and engineering professionals to solve large scale computing problems. In reality, there are already huge numbers of grid computing facilities distributed around the world, each one having been created to serve a particular group of scientists such as weather forecasters, or a group of users such as stock markets. However, the need to extend the functionalities of current grid systems lends itself to the consideration of grid evolution. This allows the combination of many disjunct grids into a single powerful grid that can operate as one vast computational resource, as well as for grid environments to be flexible, to be able to change and to evolve. The rationale for grid evolution is the current rapid and increasing advances in both software and hardware. Evolution means adding or removing capabilities. This research defines grid evolution as adding new functions and/or equipment and removing unusable resources that affect the performance of some nodes. This thesis produces a new technique for grid evolution, allowing it to be seamless and to operate at run time. Within grid computing, evolution is an integration of software and hardware and can be of two distinct types, external and internal. Internal evolution occurs inside the grid boundary by migrating special resources such as application software from node to node inside the grid. While external evolution occurs between grids. This thesis develops a framework for grid evolution that insulates users from the complexities of grids. This framework has at its core a resource broker together with a grid monitor to cope with internal and external evolution, advance reservation, fault tolerance, the monitoring of the grid environment, increased resource utilisation and the high availability of grid resources. The starting point for the present framework of grid evolution is when the grid receives a job whose requirements do not exist on the required node which triggers grid evolution. If the grid has all the requirements scattered across its nodes, internal evolution enabling the grid to migrate the required resources to the required node in order to satisfy job requirements ensues, but if the grid does not have these resources, external evolution enables the grid either to collect them from other grids (permanent evolution) or to send the job to other grids for execution (just in time) evolution. Finally a simulation tool called (EVOSim) has been designed, developed and tested. It is written in Oracle 10g and has been used for the creation of four grids, each of which has a different setup including different nodes, application software, data and polices. Experiments were done by submitting jobs to the grid at run time, and then comparing the results and analysing the performance of those grids that use the approach of evolution with those that do not. The results of these experiments have demonstrated that these features significantly improve the performance of grid environments and provide excellent scheduling results, with a decreasing number of rejected jobs.
53

A flexible model supporting QoS and reallocation for grid applications

Al Bodour, R. January 2011 (has links)
The rise of business-oriented and commercial applications for Grid computing environments has recently gathered pace. Grid computing traditionally has been linked with scientific environments, where heterogeneous resources provided by Grid systems and infrastructures were employed for carrying out computationally-intensive and data-intensive scientific experiments or applications that may have not been possible before. The natural progression is that business-oriented applications will look to build on this success and utilise the large number of heterogeneous Grid resources including computational resources such as CPUs and memory and storage resources such as disk space, potentially available. The success of introducing these applications into the mainstream is directly related to whether service providers can deliver a level of Quality of Service (QoS) to a consumer and the ability of the consumer to request high-level QoS such as the numbers of CPUs required or the RAM required. QoS refers to the guidelines and requirements requested by a user/consumer from the service providers and resources. The communication and agreement establishment processes between user and provider must be defined clearly to accommodate a new type of user where knowledge of the underlying infrastructure cannot be assumed. QoS parameters have generally been defined at the Grid resource level using low level definitions. This tailors to specific applications and models related to scientific domains where brokering, scheduling and QoS delivery is designed for specific applications within specific domains. This thesis presents a flexible model for high-level QoS requests. Business Grid Quality of Service (BGQoS) is introduced for business-oriented and commercial Grid applications which may wish to make use of the resources made available by Grid system environments. BGQoS allows GRCs (Grid Resource Consumers) to specify varying types of high-level QoS requirements which are delivered via querying up-to-date resource information, matchmaking and monitoring operations. Moreover, we present dynamically calculated metrics for measuring QoS such as reliability, increasing the accuracy of meeting the GRC’s requirements. On the other hand GRPs (Grid Resource Provider) are also capable of advertising their resources, their capabilities, their usage policies and availability both locally and globally. This leads to a flexible model that could be carried across domains without altering the core operations and which could easily be expanded in order to accommodate different types of GRC, resources and applications.
54

An Investigation of Run-time Operations in a Heterogeneous Desktop Grid Environment: The Texas Tech University Desktop Grid Case Study

Perez, Jerry Felix 01 January 2013 (has links)
The goal of the dissertation study was to evaluate the existing DG scheduling algorithm. The evaluation was developed through previously explored simulated analyses of DGs performed by researchers in the field of DG scheduling optimization and to improve the current RT framework of the DG at TTU. The author analyzed the RT of an actual DG, thereby enabling other investigators to compare theoretical results with the results of this dissertation case study. Two statistical methods were used to formulate and validate predictive models: multiple linear regression and graphical exploratory data analysis techniques. Using both statistical methods, the author was able to determine that the theoretical model was able to predict the significance of four independent variables of resource fragmentation, computational volatility, resource management, and grid job scheduling on the dependent variables quality of service and job performance affecting RT. After an experimental case study analysis of the DG variables, the author identified the best DG resources to perform optimization of run-time performance of DG at TTU. The projected outcome of this investigation is the improved job scheduling techniques of the DG at TTU.
55

Planificación dinámica sobre entornos grid

Bertogna, Mario Leandro 04 September 2013 (has links)
El objetivo de esta Tesis es el análisis para la gestión de entornos virtuales de manera eficiente. En este sentido, se realizó una optimización sobre el middleware de planificación en forma dinámica sobre entornos de computación Grid, siendo la meta a alcanzar la asignación y utilización óptima de recursos para la ejecución coordinada de tareas. Se investigó en particular la interacción entre servicios Grid y la problemática de la distribución de tareas en meta-organizaciones con requerimientos de calidad de servicio no trivial, estableciendo una relación entre la distribución de tareas y las necesidades locales pertenecientes a organizaciones virtuales. La idea tuvo origen en el estudio de laboratorios virtuales y remotos para la creación de espacios virtuales. En muchas organizaciones públicas y de investigación se dispone de gran cantidad de recursos, pero estos no siempre se encuentran accesibles, debido a la distancia geográfica, o no se dispone de la capacidad de interconectarlos para lograr un fin común. El concepto de espacio virtual introduce una capa de abstracción sobre estos recursos logrando independencia de ubicación y la interactividad entre dispositivos heterogéneos, logrando de esta manera hacer uso eficiente de los medios disponibles. Durante el desarrollo se ha experimentado y logrado la implementación de un entorno para la generación de espacios virtuales. Se ha definido la infraestructura, se implementaron dos tipos de laboratorios y se ha propuesto una optimización para lograr el máximo aprovechamiento en un entorno para aplicaciones paralelas. Actualmente estos conceptos han evolucionando y algunas de las ideas publicadas se han implementado en prototipos funcionales para infraestructuras comerciales, si bien aún se encuentra en investigación la planificación sobre centros de cómputos para miles de equipos.
56

Personal mobile grids with a honeybee inspired resource scheduler

Kurdi, Heba Abdullataif January 2010 (has links)
The overall aim of the thesis has been to introduce Personal Mobile Grids (PMGrids) as a novel paradigm in grid computing that scales grid infrastructures to mobile devices and extends grid entities to individual personal users. In this thesis, architectural designs as well as simulation models for PM-Grids are developed. The core of any grid system is its resource scheduler. However, virtually all current conventional grid schedulers do not address the non-clairvoyant scheduling problem, where job information is not available before the end of execution. Therefore, this thesis proposes a honeybee inspired resource scheduling heuristic for PM-Grids (HoPe) incorporating a radical approach to grid resource scheduling to tackle this problem. A detailed design and implementation of HoPe with a decentralised self-management and adaptive policy are initiated. Among the other main contributions are a comprehensive taxonomy of grid systems as well as a detailed analysis of the honeybee colony and its nectar acquisition process (NAP), from the resource scheduling perspective, which have not been presented in any previous work, to the best of our knowledge. PM-Grid designs and HoPe implementation were evaluated thoroughly through a strictly controlled empirical evaluation framework with a well-established heuristic in high throughput computing, the opportunistic scheduling heuristic (OSH), as a benchmark algorithm. Comparisons with optimal values and worst bounds are conducted to gain a clear insight into HoPe behaviour, in terms of stability, throughput, turnaround time and speedup, under different running conditions of number of jobs and grid scales. Experimental results demonstrate the superiority of HoPe performance where it has successfully maintained optimum stability and throughput in more than 95% of the experiments, with HoPe achieving three times better than the OSH under extremely heavy loads. Regarding the turnaround time and speedup, HoPe has effectively achieved less than 50% of the turnaround time incurred by the OSH, while doubling its speedup in more than 60% of the experiments. These results indicate the potential of both PM-Grids and HoPe in realising futuristic grid visions. Therefore considering the deployment of PM-Grids in real life scenarios and the utilisation of HoPe in other parallel processing and high throughput computing systems are recommended.
57

Research and development of accounting system in grid environment

Chen, Xiaoyn January 2010 (has links)
The Grid has been recognised as the next-generation distributed computing paradigm by seamlessly integrating heterogeneous resources across administrative domains as a single virtual system. There are an increasing number of scientific and business projects that employ Grid computing technologies for large-scale resource sharing and collaborations. Early adoptions of Grid computing technologies have custom middleware implemented to bridge gaps between heterogeneous computing backbones. These custom solutions form the basis to the emerging Open Grid Service Architecture (OGSA), which aims at addressing common concerns of Grid systems by defining a set of interoperable and reusable Grid services. One of common concerns as defined in OGSA is the Grid accounting service. The main objective of the Grid accounting service is to ensure resources to be shared within a Grid environment in an accountable manner by metering and logging accurate resource usage information. This thesis discusses the origins and fundamentals of Grid computing and accounting service in the context of OGSA profile. A prototype was developed and evaluated based on OGSA accounting-related standards enabling sharing accounting data in a multi-Grid environment, the World-wide Large Hadron Collider Grid (WLCG). Based on this prototype and lessons learned, a generic middleware solution was also implemented as a toolkit that eases migration of existing accounting system to be standard compatible.
58

Massively parallel computing for particle physics

Preston, Ian Christopher January 2010 (has links)
This thesis presents methods to run scientific code safely on a global-scale desktop grid. Current attempts to harness the world’s idle desktop computers face obstacles such as donor security, portability of code and privilege requirements. Nereus, a Java-based architecture, is a novel framework that overcomes these obstacles and allows the creation of a globally-scalable desktop grid capable of executing Java bytecode. However, most scientific code is written for the x86 architecture. To enable the safe execution of unmodified scientific code, we created JPC, a pure Java x86 PC emulator. The Nereus framework is applied to two tasks, a trivially parallel data generation task, BlackMax, and a parallelization and fault tolerance framework, Mycelia. Mycelia is an implementation of the Map-Reduce parallel programming paradigm. BlackMax is a microscopic blackhole event generator, of direct relevance for the Large Hadron Collider (LHC). The Nereus based BlackMax adaptation dramatically speeds up the production of data, limited only by the number of desktop machines available.
59

Survey of Autonomic Computing and Experiments on JMX-based Autonomic Features

Azzam, Adel R 13 May 2016 (has links)
Autonomic Computing (AC) aims at solving the problem of managing the rapidly-growing complexity of Information Technology systems, by creating self-managing systems. In this thesis, we have surveyed the progress of the AC field, and studied the requirements, models and architectures of AC. The commonly recognized AC requirements are four properties - self-configuring, self-healing, self-optimizing, and self-protecting. The recommended software architecture is the MAPE-K model containing four modules, namely - monitor, analyze, plan and execute, as well as the knowledge repository. In the modern software marketplace, Java Management Extensions (JMX) has facilitated one function of the AC requirements - monitoring. Using JMX, we implemented a package that attempts to assist programming for AC features including socket management, logging, and recovery of distributed computation. In the experiments, we have not only realized the powerful Java capabilities that are unknown to many educators, we also illustrated the feasibility of learning AC in senior computer science courses.
60

MidHPC: Um suporte para a execução transparente de aplicações em grids computacionais / MidHPC: a support for transparent application execution in computational grids

Andrade Filho, José Augusto 14 May 2008 (has links)
Pesquisas em sistemas paralelos e distribuídos de alto desempenho apresentam limitações no que se refere a análise, projeto, implementação e execução automática e transparente de aplicações. Essas limitações motivaram o projeto do MidHPC (do inglês Middleware for High Performance Computing, ou seja, Middleware para Computação de Alto Desempenho), que balanceia transparente e automaticamente cargas de trabalho considerando a capacidade dos recursos computacionais e o comportamento das aplicações envolvendo: processamento, acesso a disco, memória e rede. Para utilizar todo o potencial do MidHPC, aplicações devem ser escritas utilizando o modelo de programação concorrente, tal como o padrão POSIX de threads (pthreads). Aplicações desenvolvidas seguindo esse modelo de programação podem ser executadas em ambientes de Grid sem alteração de código fonte ou recompilação. Durante a execução, tarefas de uma mesma aplicação paralela comunicam-se, transparentemente, por meio de um sistema de memória compartilhada distribuída. O objetivo deste trabalho foi desenvolver alguns dos módulos do projeto MidHPC e integrar demais ferramentas que haviam sido previamente desenvolvidas pelo grupo. Este trabalho permite aplicar, em ambientes reais, todos os conceitos de escalonamento de processos estudados e desenvolvidos durante o projeto MidHPC / Current researches on parallel and distributed systems present limitations regarding the analysis, design, implementation and automatic execution of high performance applications. Those limitations motivated the design of MidHPC (Middleware for High Performance Computing), which transparently and automatically balances workloads considering computing resources capacities and application behavior such as: processing, network, memory and disc accesses. In order to use all of the MidHPC potential, applications must be developed following the concurrent programming model, using the POSIX thread standard (pthreads). Applications developed according to this programming model can be executed in the Grid environment with no source code modification nor recompilation. During the execution, tasks of the same application communicate, transparently, using a distributed shared memory system. The objective of this master thesis was to develop modules of the MidHPC project and integrate tools that were previously developed by the research group. This work allows applying, in real-world environments, all process scheduling concepts studied and developed during the MidHPC project

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