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An efficient system-oriented grid scheduler based on a fuzzy matchmaking approach

ENGINEERING WITH COMPUTERS 2013年第2期29卷 185-206页

作者： Saleh, Ahmed I. Mansoura Univ Fac Engn Dept Comp Engn & Syst Mansoura Egypt

computational grids have become an appealing research area as they solve compute-intensive problems within the scientific community and in industry. A Grid computational power is aggregated from a huge set of distributed heterogeneous workers;hence, it is becoming a mainstream technology for large-scale distributed resource sharing and system integration. Unfortunately, current grid schedulers suffer from the haste problem, which is the schedule inability to successfully allocate all input tasks. Accordingly, some tasks fail to complete execution as they are allocated to unsuitable workers. Others may not start execution as suitable workers are previously allocated to other peers. This paper is the first to introduce the scheduling haste problem. It also presents a reliable grid scheduler. The proposed scheduler selects the most suitable worker to execute an input grid task using a fuzzy inference system. Hence, it minimizes the turnaround time for a set of grid tasks. Moreover, our scheduler is a system-oriented one as it avoids the scheduling haste problem. Experimental results have shown that the proposed scheduler outperforms traditional grid schedulers as it introduces a better scheduling efficiency.

关键词： computational grids Scheduling Fuzzy logic Haste problem System-Oriented Schedulers

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Allocation strategies for utilization of space-shared resources in Bag of Tasks grids

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FUTURE GENERATION COMPUTER SYSTEMS-THE INTERNATIONAL JOURNAL OF ESCIENCE 2008年第5期24卷 331-341页

作者： De Rose, Cesar A. F. Ferreto, Tiago Calheiros, Rodrigo N. Cirne, Walfredo Costa, Lauro B. Fireman, Daniel Univ Fed Campina Grande Dept Sistemas & Computacao Campina Grande Brazil Pontificia Univ Catolica Rio Grande do Sul Porto Alegre RS Brazil

As the adoption of grid computing in organizations expands, the need for wise utilization of different types of resource also increases. A volatile resource, such as a desktop computer, is a common type of resource found in grids. However, using efficiently other types of resource, such as space-shared resources, represented by parallel supercomputers and clusters of workstations, is extremely important, since they can provide a great amount of computation power. Using space-shared resources in grids is not straightforward since they require jobs a priori to specify some parameters, such as allocation time and amount of processors. Current solutions (e.g. Grid Resource and Allocation Management (GRAM)) are based on the explicit definition of these parameters by the user. On the other hand, good progress has been made in supporting Bag-of-Tasks (BoT) applications on grids. This is a restricted model of parallelism on which tasks do not communicate among themselves, making recovering from failures a simple matter of reexecuting tasks. As such, there is no need to specify a maximum number of resources, or a period of time that resources must be executing the application, such as required by space-shared resources. Besides, this state of affairs makes leverage from space-shared resources hard for BoT applications running on grid. This paper presents an Explicit Allocation Strategy, in which an adaptor automatically fits grid requests to the resource in order to decrease the turn-around time of the application. We compare it with another strategy described in our previous work, called Transparent Allocation Strategy, in which idle nodes of the space-shared resource are donated to the grid. As we shall see, both strategies provide good results. Moreover, they are complementary in the sense that they fulfill different usage roles. The Transparent Allocation Strategy enables a resource owner to raise its utilization by offering cycles that would otherwise go wasted, while p

关键词： computational grids resource management space-shared resources bag-of-tasks

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The Gateway computational Web portal

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CONCURRENCY AND COMPUTATION-PRACTICE & EXPERIENCE 2002年第13-15期14卷 1411-1426页

作者： Pierce, ME Youn, C Fox, GC Florida State Univ Sch Comp Sci & Informat Technol Tallahassee FL 32306 USA Syracuse Univ Dept Elect Engn & Comp Sci Syracuse NY 13244 USA Indiana Univ Community Grid Lab Dept Comp Sci Sch Informat Bloomington IN 47405 USA Indiana Univ Dept Phys Bloomington IN 47405 USA

In this paper we describe the basic services and architecture of Gateway, a commodity-based Web portal that provides secure remote access to unclassified Department of Defense computational resources. The portal-consists of a dynamically generated, browser-based user interface supplemented by client applications and a distributed middle tier, WebFlow. WebFlow provides a coarse-grained approach to accessing both stand-alone and Grid-enabled back-end computing resources. We describe in detail the implementation of basic portal features such as job submission, file transfer, and job monitoring and discuss how the portal addresses security requirements of the deployment centers. Finally, we outline future plans, including integration of Gateway with Department of Defense testbed grids. Copyright (C) 2002 John Wiley Sons,Ltd.

关键词： computational portals computing environments computational grids

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Parallel cooperative meta-heuristics on the computational grid. A case study: the bi-objective Flow-Shop problem

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PARALLEL COMPUTING 2006年第9期32卷 643-659页

作者： Melab, N. Mezmaz, M. Talbi, E. -G. INRIA Futurs Lab Informat Fondamentale Lille UMR 8022 CNRS F-59655 Villeneuve France

In this paper, we contribute with the first results on parallel cooperative multi-objective meta-heuristics on computational grids. We particularly focus on the island model and the multi-start model and their cooperation. We propose a checkpointing-based approach to deal with the fault tolerance issue of the island model. Nowadays, existing Dispatcher-Worker grid middlewares are inadequate for the deployment of parallel cooperative applications. Indeed, these need to be extended with a software layer to support the cooperation. Therefore, we propose a Linda-like cooperation model and its implementation on top of XtremWeb. This middleware is then used to develop a parallel meta-heuristic applied to a bi-objective Flow-Shop problem using the two models. The work has been experimented on a multi-domain education network of 321 heterogeneous Linux PCs. The preliminary results, obtained after more than 10 days, demonstrate that the use of grid computing allows to fully exploit effectively different parallel models and their combination for solving large-size problem instances. An improvement of the effectiveness by over 60% is realized compared to serial metaheuristic. (c) 2006 Elsevier B.V. All rights reserved.

关键词： computational grids multi-objective meta-heuristics parallelism cooperation Flow-Shop problem

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Transient wave envelope elements for wave problems

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JOURNAL OF SOUND AND VIBRATION 1996年第1期192卷 245-261页

作者： Astley, RJ UNIV CANTERBURY DEPT ENGN MECH CANTERBURY NEW ZEALAND

A novel family of infinite wave envelope elements is described which can be used in conjunction with conventional finite elements to model the transient wave equation in unbounded regions. The elements are obtained by applying an inverse Fourier transformation to a mapped wave envelope formulation in the frequency domain. The discrete transient equations obtained in this way can be applied to two-dimensional and three-dimensional problems without restriction, being valid over a full range of excitation frequencies. The effectiveness and accuracy of the method is demonstrated in application to simple test cases which involve the calculation of transient sound fields generated by pulsating spheres and cylinders excited from rest in an unbounded region. Test solutions are compared to analytic solutions and to finite element solutions obtained by using large computational grids which extend beyond the region influenced by the transient disturbance. (C) 1996 Academic Press Limited

关键词： Acoustical radiation Boundary-conditions Infinite elements Propagation Equations CASING INSPECTION FULL-SCALE waveforms excitation frequency computational grids propagation Boundary conditions FINITE ELEMENT wave envelope Fourier Transform

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On the development of high-performance C++ object-oriented code with application to an explicit edge-based fluid dynamics scheme

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COMPUTERS & FLUIDS 2004年第10期33卷 1291-1304页

作者： Malan, AG Lewis, RW Univ Pretoria Dept Mech & Aeronaut Engn ZA-0002 Pretoria South Africa Univ Coll Swansea Dept Engn Mech Swansea SA2 8PP W Glam Wales

Object-oriented techniques are investigated and algorithms constructed for developing efficient explicit edge-based finite-volume code. C++ was the chosen programming language and the developed algorithms include effecting reduced data trafficking and balanced dynamic-static polymorphism as well as a proposed novel caching technique. These are implemented into an actual object-oriented computational fluid dynamics (CFD) code and numerical experiments conducted on PC and SGI platforms to assess improved performance. Significant reductions in both required memory and computational times are demonstrated for computational meshes ranging from small to large. (C) 2004 Elsevier Ltd. All rights reserved.

关键词： Explicit Small computational time object orientation Codes algorithms Hydrodynamics Personal computers computational grids

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A UTILITY-BASED REPUTATION MODEL FOR GRID RESOURCE MANAGEMENT SYSTEM

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COMPUTING AND INFORMATICS 2014年第5期33卷 1139-1167页

作者： Kussul, Olga Kussul, Nataliia Skakun, Sergii Natl Tech Univ Ukraine Kyiv Polytech Inst Inst Phys & Technol 37 Prospect Peremogy UA-03056 Kiev Ukraine Space Res Inst NASU SSAU UA-03680 Kiev Ukraine

In this paper we propose extensions to the existing utility-based reputation model for virtual organizations (VOs) in grids, and present a novel approach for integrating reputation into grid resource management system. The proposed extensions include: incorporation of statistical model of user behaviour (SMUB) to assess user reputation;a new approach for assigning initial reputation to a new entity in a VO;capturing alliance between consumer and resource;time decay and score functions. The addition of the SMUB model provides robustness and dynamics to the user reputation model comparing to the policy-based user reputation model in terms of adapting to user actions. We consider a problem of integrating reputation into grid scheduler as a multi-criteria optimization problem. A non-linear trade-off scheme is applied to form a composition of partial criteria to provide a single objective function. The advantage of using such a scheme is that it provides a Pareto-optimal solution partially satisfying criteria with corresponding weights. Experiments were run to evaluate performance of the model in terms of resource management using data collected within the EGEE Grid-Observatory project. Results of simulations showed that on average a 45% gain in performance can be achieved when using a reputation-based resource scheduling algorithm.

关键词： computational grids reputation model scheduling algorithm resource allocation utility computing neural network

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Role of flow-consistent grid in CFD

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COMPUTERS & FLUIDS 1999年第3期28卷 265-280页

作者： Kumar, A CSIR Ctr Math Modelling & Comp Simulat Bangalore 560037 Karnataka India

computational grids can play a crucial role in accurate CFD (computational fluid dynamics) simulations. This is shown here through the example of leading-edge vortex flow. Conventional grids for how over sharp-edged delta wings do not resolve the near-apex flow due;to dissimilar length scales of the flow and the grid. This in turn can affect the simulation of many vortex related phenomena. A grid that is consistent with the special nature of the how is required to overcome the difficulty. The Euler simulation of a transonic vortex is considered where employment of a flow-consistent grid is shown to give a well-resolved vortex with cross-flow shock and also the shock-induced secondary vortex, right from the apex. On the other hand, when a conventional grid is employed these features are absent in the near-apex how, and the subsequent how development is seriously affected. Euler simulation of subsonic vortex breakdown has also been considered. In this case the employment of a flow-consistent grid has led to an unravelling of the fine details of the breakdown process. (C) 1999 Elsevier Science Ltd. All rights reserved.

关键词： computational fluid dynamics Computer simulation Vortex flow Equations of motion Transonic flow Subsonic flow Flow-consistent grid computational grids

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Three Dimensional Computations and Experimental Comparisons for a Large-Scale Proton Exchange Membrane Fuel Cell

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JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2016年第7期163卷 F744-F751页

作者： Hao, Liang Moriyama, Koji Gu, Wenbin Wang, Chao-Yang Penn State Univ Electrochem Engine Ctr ECEC University Pk PA 16802 USA Penn State Univ Electrochem Engine Ctr ECEC University Pk PA 16802 USA Honda Res & Dev Co Ltd Haga Tochigi 3213393 Japan Gen Motors Pontiac MI 48340 USA

Comprehensive experimental validation for a large-scale proton exchange membrane (PEM) fuel cell is performed in this work using the multiphase-mixture (M2) model on a 9.2 million grid-point computational mesh. The predicted fuel cell voltage, high-frequency resistance, as well as current density and temperature distributions all show good agreement with the extensive experimental data under various operating conditions and for two Pt loadings of 0.3 mg/cm(2) and 0.1 mg/cm(2). In particular, the present study demonstrates quantitative comparisons of liquid water distribution in the PEM fuel cell with neutron imaging measurements. Such a comprehensive validation against a range of measurements points to the readiness of applying the M2 model to design and develop the next generation of PEM fuel cells and stacks. (C) 2016 The Electrochemical Society. All rights reserved.

关键词： Experimental data cell voltage Ranging measurements Operating conditions grid point Current density Readiness Polymer electrolyte membrane fuel cells Water distribution high frequency resistance computational grids fuel batteries

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Simulating three-dimensional aeronautical flows on mixed block-structured/semi-structured/unstructured meshes

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INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS 2002年第3期39卷 213-246页

作者： Shaw, JA Peace, AJ Aircraft Res Assoc Ltd Bedford MK41 7PF England

The design requirements of a computational fluid dynamics (CFD) method for modelling high Reynolds number flows over complete aircraft are reviewed. It is found that the specifications are unlikely to be met by an approach based on the sole use of either structured or unstructured grids. Instead, it is proposed that a hybrid combination of these grids is appropriate. Techniques for developing such meshes are given and the process of establishing the data structure defining the meshes described. Details of a flow algorithm which operates on a hybrid mesh are presented. A description is given of the suitability and generation of hybrid grids for a number of examples, and results from flow simulations shown. Finally, issues still to be addressed in the practical use of these meshes are discussed. Copyright (C) 2002 John Wiley Sons, Ltd.

关键词： computational grids three-dimensional flow finite volume method Euler equations of motion vortical flow transonic flow

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