Adaptive resource management (ARM) technology has emerged as a way to: (1) support applications' varying resource needs, and (2) provide reusable solutions to commonly occurring problems. Most existent works on AR...
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Adaptive resource management (ARM) technology has emerged as a way to: (1) support applications' varying resource needs, and (2) provide reusable solutions to commonly occurring problems. Most existent works on ARM have focused on centralized approaches. However, centralized ARMs are not scalable, which may result in slow responses and wrong allocation decisions based on inaccurate system state information. In this paper, we show how to address these problems with a decentralized resource management approach. Based on social models, the approach appears to have the potential to provide prompt and accurate allocation of resources.
The emergence of the computational Grid and the potential for seamless aggregation, integration and interactions has made it possible to conceive a new generation of realistic, scientific and engineering simulations o...
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The emergence of the computational Grid and the potential for seamless aggregation, integration and interactions has made it possible to conceive a new generation of realistic, scientific and engineering simulations of complex physical phenomena. The inherently heterogeneous and dynamic nature of these application and the Grid presents significant runtime management challenges. In this paper we extend the PRAGMA framework to enable self adapting, self optimizing runtime management of dynamically adaptive applications. Specifically, we present the design, prototype implementation and initial evaluation of policies and mechanisms that enable PRAGMA to autonomically manage, adapt and optimize structured adaptive mesh refinement applications (SAMR) based on current system and application state and predictive models for system behavior and application performance. We use the 3-D adaptive Richtmyer-Meshkov compressible fluid dynamics application and Beowulf clusters at Rutgers University, University of Arizona, and NERSC to develop our performance models, and define and evaluate our adaptation policies. In our prototype, the predictive performance models capture computational and communicational loads and, along with current system state, adjust processors capacities at runtime to enable the application to adapt and optimize its performance.
The paper presents a model that is useful for developing resource allocation algorithms for distributed real-time systems that operate in dynamic environments. Interesting aspects of the model include dynamic environm...
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The paper presents a model that is useful for developing resource allocation algorithms for distributed real-time systems that operate in dynamic environments. Interesting aspects of the model include dynamic environments, utility and service levels, which provide a means for graceful degradation in resource-constrained situations and support optimization of the allocation of resources. The paper also provides an allocation algorithm that illustrates how to use the model for producing feasible, optimal resource allocations.
Informal presentations are a lightweight means for fast and convenient communication of ideas. People communicate their ideas to others on paper and whiteboards, which afford fluid sketching of graphs, words and other...
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ISBN:
(纸本)1581136218
Informal presentations are a lightweight means for fast and convenient communication of ideas. People communicate their ideas to others on paper and whiteboards, which afford fluid sketching of graphs, words and other expressive symbols. Unlike existing authoring tools that are designed for formal presentations, we created SketchPoint to help presenters design informal presentations via freeform sketching. In SketchPoint, presenters can quickly author presentations by sketching slide content, overall hierarchical structures and hyperlinks. To facilitate the transition from idea capture to communication, a note-taking workspace was built for accumulating ideas and sketching presentation outlines. Informal feedback showed that SketchPoint is a promising tool for idea communication. Copyright 2003 ACM.
The problems related to supporting multicast connections with quality of service (QoS) requirements are studied. We investigate the problem of optimal resource allocation in the context of performance dependent costs....
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The problems related to supporting multicast connections with quality of service (QoS) requirements are studied. We investigate the problem of optimal resource allocation in the context of performance dependent costs. In this context each network element can offer several QoS guarantees, each associated with a different cost. This is a natural extension to the commonly used bi-criteria model, where each link is associated with a single delay and a single cost. This framework is simple yet strong enough to model many practical interesting networking problems. The fundamental multicast resource allocation problem under this framework is how to optimally allocate QoS requirements on the links of the multicast tree. One needs to partition the end-to-end QoS requirement along the various paths in a tree. The goal is to satisfy the end-to-end QoS requirement with minimum cost. Previous studies under this framework considered single-source multicast connections, where the end-to-end QoS requirement is specified from the source to all other multicast group members. In this paper we extend these results to the more general, and considerably harder case of multicast sessions, where the end-to-end requirement hold for every path between any two multicast group members. Our aim is to provide rigorous solutions, with proven performance guarantees, by way of algorithmic analysis. The problem under investigation is NP hard for general cost functions, thus we first present a pseudopolynomial exact solution. From this solution we derive two efficient /spl epsi/-approximate solutions. One achieves optimal cost, but may violate the end-to-end delay requirement by a factor of (1 + /spl epsi/), and the other strictly obeys the bounds and achieves a cost within a factor of (1+/spl epsi/) of the optimum. Furthermore, we present improved results for discrete cost functions, and give a simple linear-time exact polynomial solution for a specific, and practically interesting, family of convex
In this paper we propose a method to create discrete abstraction of state space behavior for continuous-time systems based on gradient analysis of the system dynamics. Then we describe how to use such a discrete model...
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In this paper we propose a method to create discrete abstraction of state space behavior for continuous-time systems based on gradient analysis of the system dynamics. Then we describe how to use such a discrete model to design a supervisory controller for a given safety specification for the system. Finally we provide an entropy measure of nondeterminism, which can be used to evaluate the quality of the result discrete model as the degree of nondeterminism in that model.
This paper conducts an empirical analysis of a semiotics-based quality framework for quality assuring information models. 192 participants were trained in the concepts of the quality framework, and used it to evaluate...
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This paper conducts an empirical analysis of a semiotics-based quality framework for quality assuring information models. 192 participants were trained in the concepts of the quality framework, and used it to evaluate models represented in an extended Entity Relationship (ER) language. A randomised, double-blind design was used, in which each participant independently reviewed multiple models and each model was evaluated by multiple reviewers. A combination of quantitative and qualitative analysis techniques were used to evaluate the results, including reliability analysis, validity analysis, interaction analysis, influence analysis, defect pattern analysis and task accuracy analysis.. An analysis was also conducted of the framework's likelihood of adoption in practice. The study provides strong support for the validity of the framework and suggests that it is likely to be adopted in practice, but raises questions about its reliability and the ability of participants to use it to accurately identify defects. The research findings provide clear directions for improvement of the framework. The research methodology used provides a general approach to empirical validation of quality frameworks.
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