The distributed ASCI supercomputer project

The Distributed ASCI Supercomputer (DAS) is a homogeneous wide-area distributed system consisting of four cluster computers at different locations. DAS has been used for research on communication software, parallel languages and programming systems, schedulers, parallel applications, and distributed applications. The paper gives a preview of the most interesting research results obtained so far in the DAS project

Estudo sobre processamento maciçamente paralelo na internet

Orientador: Marco Aurélio Amaral HenriquesTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de ComputaçãoResumo: Este trabalho estuda a possibilidade de aproveitar o poder de processamento agregado dos computadores conectados pela Internet para resolver problemas de grande porte. O trabalho apresenta um estudo do problema tanto do ponto de vista teórico quanto prático. Desde o ponto de vista teórico estudam-se as características das aplicações paralelas que podem tirar proveito de um ambiente computacional com um grande número de computadores heterogêneos fracamente acoplados. Desde o ponto de vista prático estudam-se os problemas fundamentais a serem resolvidos para se construir um computador paralelo virtual com estas características e propõem-se soluções para alguns dos mais importantes como balanceamento de carga e tolerância a falhas. Os resultados obtidos indicam que é possível construir um computador paralelo virtual robusto, escalável e tolerante a falhas e obter bons resultados na execução de aplicações com alta razão computação/comunicaçãoAbstract: This thesis explores the possibility of using the aggregated processing power of computers connected by the Internet to solve large problems. The issue is studied both from the theoretical and practical point of views. From the theoretical perspective this work studies the characteristics that parallel applications should have to be able to exploit an environment with a large, weakly connected set of computers. From the practical perspective the thesis indicates the fundamental problems to be solved in order to construct a large parallel virtual computer, and proposes solutions to some of the most important of them, such as load balancing and fault tolerance. The results obtained so far indicate that it is possible to construct a robust, scalable and fault tolerant parallel virtual computer and use it to execute applications with high computing/communication ratioDoutoradoEngenharia de ComputaçãoDoutor em Engenharia Elétric

A dynamic prediction and monitoring framework for distributed applications

This research builds on an application performance prediction and characterisation environment (known as PACE), whose aim is to characterise the performance-critical elements of both an application and its target execution environment and deduce from this model a predicted behaviour of the application prior to its execution. Underlying the research presented in this thesis are a number of themes: the tasks involved in the performance characterisation of applications and how this might be semi- automated: the level of abstraction at which these characterisations are performed in order to maintain a sufficient predictive accuracy: the automated refinement of these characterisations from runtime performance data: the extension of both the target programming languages and the class of application at which these techniques are aimed. In this thesis a number of novel extensions to PACE are described. These include: a new transaction-based performance characterisation language that provides a flexible framework for describing broader classes of application; a performance monitoring framework (based on an extension to the OpenGroup’s Application Response Measurement (ARM) standard) for the runtime monitoring of an application's data-dependent components and the automated refinement of performance models: an adaptation of this performance characterisation for the prediction of Java applications. These contributions are demonstrated through their application to a number of scientific kernels. This thesis also documents how these predictive results can be used in a real-time distributed runtime management environment, and also how these techniques can be applied to non-scientific codes, in particular to an IBM request-driven distributed web services demonstrator