Withthe advent of the Grid, task scheduling in heterogeneous environments becomes more and more important. Of particular interest is the fact that especially in scientific experiments a non negligible amount of data ...
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ISBN:
(纸本)9780769527369
Withthe advent of the Grid, task scheduling in heterogeneous environments becomes more and more important. Of particular interest is the fact that especially in scientific experiments a non negligible amount of data must be transferred to the processing node before a task can commence execution. Given bandwidth constraints, scheduling both computations and data transfers is required. In this paper we first develop a suitable model that captures heterogeneity in the processing nodes while imposing communication constraints. We proceed by proposing scheduling heuristics withthe aim of minimizing the total makespan of a set of independent tasks. through a series of experiments we illustrate the potential of a particular heuristic that is based on backfilling.
the pricing of a portfolio of financial instruments is a common and important Computational problem in financial engineering. In addition to pricing, a portfolio or risk manager may be interested in determining ail ef...
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ISBN:
(纸本)3540290672
the pricing of a portfolio of financial instruments is a common and important Computational problem in financial engineering. In addition to pricing, a portfolio or risk manager may be interested in determining ail effective hedging C strategy, computingthe value at risk, or valuing the portfolio under several different scenarios. Because of the size of many practical portfolios and the complexity of modern financial instruments the computing time to solve these problems can be several hours. We demonstrate a powerful and practical method for solving these problems on clusters using web services.
In the recent years, modern complex infrastructures are built on integration and cooperation of legacy and/or new systems;the emerging technology, to primary face the involved interoperability problems, is based on we...
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ISBN:
(纸本)3540290672
In the recent years, modern complex infrastructures are built on integration and cooperation of legacy and/or new systems;the emerging technology, to primary face the involved interoperability problems, is based on web service solutions. It is based on open standards and common data formats which allow a deep cooperation among Entities and applications and guarantee strong resource sharing. In such context security plays a primary role to control access to data and functionalities offered by distributed services. In this paper we illustrate a policy-based approach to manage security and personalization, in particular we have designed a hybrid infrastructure based on web services in which policy enforcer mechanisms are managed both in a centralized way by the registry server and in a distributed way, i.e. each service implements security mechanisms to authenticate and authorize users. A case study is illustrated showing a distributed architecture for health-care applications.
In this paper we consider the problem of exact string matching algorithm based on a two-dimensional array. this has applications such as string databases, cellular automata and computational biology. the main use of t...
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GRID Application development is a hard task. Good applications should correctly use large distributed systems, whose infrastructure heavily affects the application performance. In this paper we propose a performance o...
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ISBN:
(纸本)3540290672
GRID Application development is a hard task. Good applications should correctly use large distributed systems, whose infrastructure heavily affects the application performance. In this paper we propose a performance oriented approach to GRID application development, founded on the use of a prototype language (MetaPL) for the description of the applications and the use of a heterogeneous system simulation environment (HeSSE) for performance prediction. We developed GRID simulation components for the existing simulation environment (HeSSE) and validated them. After that we extended the MetaPL language in order to explicitly support GRID application features and simulated a simple case study to show how the approach works.
In this paper we explore the parallelization of the scientific library from GNU both on shared-memory and distributed-memory architectures. A pair of classical operations, arising in sparse linear algebra and discrete...
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ISBN:
(纸本)3540290672
In this paper we explore the parallelization of the scientific library from GNU both on shared-memory and distributed-memory architectures. A pair of classical operations, arising in sparse linear algebra and discrete mathematics, allow us to identify the major challenges involved in this task, and to analyze the performance, benefits, and drawbacks of two different possible parallelization approaches.
this paper proposes the general Bayesian network as a tool for identifying critical dependencies among complex human beliefs, especially for the case of airline service industry. When we consider an overall efficacy o...
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Providing Grid users with a widely accessible, homogeneous and easy-to-use graphical interface is the foremost aim of Grid-portal development. these portals, if designed and implemented in a proper and user-friendly w...
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ISBN:
(纸本)3540290672
Providing Grid users with a widely accessible, homogeneous and easy-to-use graphical interface is the foremost aim of Grid-portal development. these portals, if designed and implemented in a proper and user-friendly way, might fuel the dissemination of Grid-technologies, hereby promoting the shift of Grid-usage from research into real life, industrial application, which is to happen in the foreseeable future, hopefully. Grid portals are quite frequently applied in order to utilize common user tasks like access control, data and application code transfers, job control and status monitoring but design, development and performance tuning of complex Grid or HPC applications are usually not supported directly by such portals. this paper introduces P-GRADE Portal being developed at MTA SZTAKL It allows users to manage the whole life-cycle of building and executing complex applications in the Grid: editing workflows, submitting jobs relying on Grid-credentials and analyzing the monitored trace-data by means of visualization.
the MaLLBa library provides skeletons to solve combinatorial optimization problems. Its main objective is to simplify the implementation of algorithms based on some commonly used techniques such as Branch and Bound, D...
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ISBN:
(纸本)3540290672
the MaLLBa library provides skeletons to solve combinatorial optimization problems. Its main objective is to simplify the implementation of algorithms based on some commonly used techniques such as Branch and Bound, Dynamic Programming and Divide and Conquer. this work is focused on the MaLLBa::DnC skeleton, which solves problems that fit in the Divide and Conquer paradigm. the user has to provide functions particularized to the problem he wants to solve. Given that functions the skeleton encapsulates all remaining work and allows the problem to be solved either in a sequential or parallel way. In this work we will present a new MP1 asynchronous peer-processor implementation of the MaLLBa::DnC skeleton where all processors are peers and behave the same way (except during the initialization phase) and where decisions are taken based only on local information. Results on a Linux cluster of PC for matrix and huge integer multiplication are presented.
In this paper we present a parallel method for finding several eigenvalues and eigenvectors of a generalized eigenvalue problem Ax = lambda Bx, where A and B are large sparse matrices. A moment-based method by which t...
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ISBN:
(纸本)3540290672
In this paper we present a parallel method for finding several eigenvalues and eigenvectors of a generalized eigenvalue problem Ax = lambda Bx, where A and B are large sparse matrices. A moment-based method by which to find all of the eigenvalues that lie inside a given domain is used. In this method, a small matrix pencil that has only the desired eigenvalues is derived by solving large sparse systems of linear equations constructed from A and B. Since these equations can be solved independently, we solve them on remote hosts in parallel. this approach is suitable for master-worker programming models. We have implemented and tested the proposed method in a grid environment using a grid RPC (remote procedure call) system called OmniRPC. the performance of the method on PC clusters that were used over a wide-area network was evaluated.
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