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1.
计算网格中动态负载平衡的分布调度模式   总被引:1,自引:0,他引:1  
网格计算下对资源进行有效的管理和调度可以提高系统的利用率.在对现有若干调度方法的研究和分析基础上,针对计算网格中的负载平衡问题,提出了一种分布式网格作业调度模型,并给出相关算法.算法通过建立主从模式的负载信息收集机制,提供给节点全局负载信息,加速重负载节点的负载转移速度.通过有效的负载平衡模式,解决资源调度中负载平衡及其可靠性问题.  相似文献   

2.
根据分布式系统的静态和动态负载均衡策略的优缺点,提出了在网格计算环境下的混合负载均衡策略.为了让网络中节点在网格计算环境中有效地执行需要大量计算的复杂任务,提出了用来评估节点效率的函数,并结合模拟实验证实了在此函数下算法的优越性.  相似文献   

3.
近年来,随着科学研究对计算资源的要求不断增加,结合分布式计算环境和互联网的网格计算已经得到越来越多研究者的关注。网格计算就是利用网络中的空闲计算资源来协助那些要求大量计算的复杂任务的执行。根据分布式系统的静态和动态负载均衡策略的优缺点,本文提出了在网格计算环境下的混合负载均衡策略。为了让网络中的节点在网格计算环境中有效地执行需要大量计算的复杂任务,并根据大量的实验总结,提出了新的用来评估节点效率的函数,较以前的函数执行效率有了提高。  相似文献   

4.
非集中调度模型下的网格资源调度研究*   总被引:1,自引:0,他引:1  
针对当前网格资源调度系统扩展性差的问题,提出了基于非集中调度模型的以保守Backfilling算法为核心的网格资源调度算法.探讨了网格任务在站点处理器数目异构情况下,网格作业多站点协同调度问题.实验仿真证明,在跨网格站的资源调度中,运用资源预留策略和多站点作业分块可以改善作业的平均响应时间,并起到负载平衡的效果.  相似文献   

5.
    
Coordination of motion between multiple robots requires the robots to sense their relative poses. Common sensors depend on maintaining a line-of-sight between the sensor and the object being sensed. When the robots move relative to one another, they must coordinate their motions to ensure that these lines-of-sight are preserved. We propose a control method to preserve desired lines-of-sight in a multi-robot system where each robot has configuration space SE(3). A key feature of the control method is its ability to reject persistent bounded disturbances, enabling its use alongside additional control tasks. We demonstrate the effectiveness of the edge-preserving control in simulations involving additional input velocities that tend to break the edges.  相似文献   

6.
    
Over the last few years, several nations around the world have set up Grids to share resources such as computers, data, and instruments to enable collaborative science, engineering, and business applications. These Grids follow a restricted organizational model wherein a Virtual Organization (VO) is created for a specific collaboration and all interactions such as resource sharing are limited to within the VO. Therefore, dispersed Grid initiatives have led to the creation of disparate Grids with little or no interaction between them. In this paper, we propose a model that: (a) promotes interlinking of islands of Grids through peering arrangements to enable InterGrid resource sharing; (b) provides a scalable structure for Grids that allow them to interconnect with one another and grow in a sustainable way; (c) creates a global Cyberinfrastructure to support e‐Science and e‐Business applications. This work identifies and proposes architecture, mechanisms, and policies that allow the internetworking of Grids and allows Grids to grow in a similar manner as the Internet. We term the structure resulting from such internetworking between Grids as the InterGrid. The proposed InterGrid architecture is composed of InterGrid Gateways responsible for managing peering arrangements between Grids. We discuss the main components of the architecture and present a research agenda to enable the InterGrid vision. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

7.
    
This paper considers the torque control problem for robots with flexible joints driven by electrical actuators. It is shown that the achievable closed-loop tracking bandwidth using PI torque controllers may be limited due to transmission zeros introduced by the load dynamics. This limitation is overcome by using positive feedback from the load motion in unison with PI torque controllers. The positive feedback is given in terms of load velocity, acceleration and jerk. Stability conditions for designing decentralized PI torque controllers are derived in terms of Routh-Hurwitz criteria. Disturbance rejection properties of the closed system are characterized and an analysis is carried out investigating the use of approximate positive feedback by omitting acceleration and/or jerk signals. The results of this paper are illustrated for a two DoF (degrees of freedom) system. Experimental results for a one DoF system are also included.  相似文献   

8.
在介绍成都区域气象中心网格计算平台基础上,为了保证资源的合理分配与网格节点负载均衡,构建了基于Gold的网格资源管理系统,并将其应用到成都区域中心网格计算平台中,通过典型应用实例分析结果表明,该系统功能丰富。大大提高了网格平台资源管理的效率。  相似文献   

9.
程宏兵  杨庚 《计算机应用》2005,25(11):2483-2485
提出了一种基于自动回归(AR)改进的主机负载预测模型,它不仅具有AR模型本身的计算成本小、预测性能稳定的优点,还对AR模型只对未来某个固定时间段的负载预测进行了改进,使之能根据作业的预测执行时间进行主机负载动态预测,同时该模型还充分体现了主机负载变化的自相似性和长期依赖性。实验结果表明,该模型达到了预期的效果。  相似文献   

10.
隐私保护问题是当前访问控制研究领域的一个热点问题.为此提出一种可信分散式访问控制机制,以实现面向客户端上下文隐私保护的访问控制.可信分散式访问控制中包含了私有可信引用监视器和主引用监视器.私有可信引用监视器在安装了可信计算环境的客户端运行,用于评估客户端的访问控制请求,签署临时访问控制凭证;主引用监视器在服务端运行,用于评估临时访问控制凭证,决定客户端的访问是否被授权.由于具体的客户端上下文数据不会发送到服务器端,因此应用可信分散式访问控制,实现如简单位置相关的基于角色的访问控制,可以在客户端上下文相关的访问控制中很好地保护客户端的上下文数据隐私;此外,由于在该机制中客户端上下文是在客户端获取和处理的,因此可信分散式访问控制也可以减轻服务器端获取访问端的上下文的负担.安全性分析和性能实验表明,文中的访问控制机制可以有效地保护客户端上下文数据隐私.  相似文献   

11.
针对当前网格计算经济中记账和支付的不足,提出了一种能够独立于计算经济模型的记账和支付体系结构.以独立的第3方完成记账数据采集;依据GSP和GSC的支付策略实现资源选择和支付;完成了一个支付算法,实现了和现实商业银行的仿真连接.  相似文献   

12.
Security is a fundamental but challenging issue in the dynamic and multi-organizational computational grid. Focusing on the closed system, traditional access control model considered static authorization decisions based on pre-assigned permissions. To facilitate collaborations and interoperations across the grid, we propose a usage control mechanism for computational grid. Our mechanism is based on the usage control model. By leveraging continuous usage control on grid services and monitoring the status and behaviors of the subjects involved in the collaborations, our mechanism improves collaboration's security. Furthermore, our mechanism enables richer and finer-grained control over authorizations on resources and services involved in collaborations and interoperations than that of traditional access control mechanisms. Our mechanism can contribute to maintain the security and interests of the service providers in the grid environment.  相似文献   

13.
网络并行计算的动态负载平衡策略   总被引:7,自引:0,他引:7  
本文主要概述动态负载平衡的概念和主要算法。  相似文献   

14.
    
Access control is an important technique in information security that allows legitimate users to gain access to and prevent unauthorized users from getting access to resources in a system. The restriction between access from a user and a shared file of the data owner can be determined by the access policy. In most existing access control models, it is assumed that all entities, including users, the third party, and cloud service provider (CSP), are in the same trust domain. However, in cloud computing environments, it is usually assumed that the CSP cannot be fully trusted, and the data owner (DO) is desired to have the absolute initiative to control data access. This article proposes a blockchain-based access control scheme for cloud computing, in which the DO maintains an access matrix to describe the access policy. Then, the public keys of all nodes and the access matrix are stored in the blockchain, to ensure the security of the proposed scheme. The DOs can encrypt the large shared files once using a symmetric key in a long time. And they also can encrypt the symmetric key in parallel using the public key of authorized users in a short time. Security analysis proves that the proposed scheme is able to prevent outsourced files from unauthorized access and collusion attack. Experimental results show that the proposed scheme outperforms the existing baselines in terms of overheads on computation and storage. On average, the computation overhead of the proposed scheme is lower than that of the scheme SVPAC, PpBAC, and Timely CP-ABE by 25.37%, 45.46%, and 36.44%, respectively. The communication overhead of the proposed scheme is lower than that of the scheme Timely CP-ABE by 17.16%, and it is more secure, although it is higher than that of the scheme SVPAC and PpBAC by 5.88% and 39.05%. And the storage overhead of the proposed scheme is lower than that of the scheme SVPAC, PpBAC, and Timely CP-ABE by 59.36%, 20.25%, and 61.88%, respectively.  相似文献   

15.
针对层次化网格模型结构,运用统计思想提出了一种新的资源分配与任务调度算法,不仅能够提高资源的利用率和系统的吞吐率,而且能够实现网格系统内部的负载平衡。算法主要包含三个功能模块,即负载跟踪模块、作业分配模块和负载监视模块。在解释了方案中各功能部件的作用及其相互之间关系的基础上,给出了相应的算法伪码。仿真实验表明,该算法是有效的。  相似文献   

16.
    
This paper presents distributed coverage algorithms for mobile sensor networks in which agents have limited power to move. Rather than making use of a constrained optimization technique, our approach accounts for power constraints by assigning non‐homogeneously time‐varying regions to each robot. This leads to novel partitions of the environment into limited‐range, generalized Voronoi regions. The motion control algorithms are then designed to ascend the gradient of several types of locational optimization functions. In particular, the objective functions reflect the global energy available to the group and different coverage criteria. As we discuss in the paper, this has an effect on limiting each agent's velocity to save energy and balance its expenditure across the network. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

17.
基于多智能体交通绿波效应分布式协同控制算法   总被引:1,自引:0,他引:1       下载免费PDF全文
徐杨  张玉林  孙婷婷  苏艳芳 《软件学报》2012,23(11):2937-2945
基于\"绿波\"效应的交通控制通过实现干道上的车流不间断地经过多个交通灯路口而不停止,是目前公认的最有效率的交通控制策略之一.然而随着城市交通规模的不断扩大,传统的集中式交通控制方法可能遇到计算和通信上的瓶颈.而当路口交通灯只能获取城市交通网络全局有限的信息时,传统的分布式控制方法可能十分低效.提出了一种基于多智能体的交通灯分布式绿波自适应控制方法.在该设计中,每一个交通灯路口通过一个非集中式的协同智能体来控制.其核心是,智能体通过预测自身下一时刻的状态进行自主决策.由于只有来自邻居路口的车辆能够直接影响当前路口下一步的状态,这一决策过程仅需要智能体通过与邻居智能体间的局部交互来完成.描述了基于多智能体交通灯分布式\"绿波\"效应的控制算法,并通过仿真实验验证了该方法在大规模城市交通系统中的可行性.  相似文献   

18.
提出了一个网格信任模型,用主观逻辑理论进行信任值的推导、综合。针对现有网格任务调度算法存在的问题,设计了一种任务和资源安全等级匹配的调度算法。通过安全需求对资源进行筛选,并使它满足最早完成时间。仿真实验表明,与传统经典网格任务调度算法比较,该算法提高了任务成功率,减少了任务完成时间,是网格环境下一种有效的资源调度模型。  相似文献   

19.
网格计算中对资源的有效预测能很好的改进任务分配和作业调度的策略,提高它们的执行效率,作为网格资源预测的核心?主机负载的预测显得尤为重要。文中提出了一种基于AR改进的主机负载预测模型,它不仅具有AR模型本身的计算成本小、预测性能稳定的优点,还对AR模型只对未来某个固定时间段的负载预测进行了改进,使之能根据作业的预测执行时间进行主机负载动态预测,同时该改进模型还充分体现了主机负载变化的自相似性和长期依赖性,实验结果表明,该模型达到了预期的效果。  相似文献   

20.
    
The accurate prediction of cost profiles of future job tasks on the nodes of clusters or grids helps users to select the cost performance profile that best suits their budgets. The current software designed to deploy job tasks uses forecasts of the target computers' future load profiles. Once the job task's future load profile is known, converting it to its cost profile needs further analysis as the cost depends on other factors such as its delays and variable background loads. This paper introduces a new charging mechanism for charging future job tasks, called the Cost Profiling Model. The model has been implemented in a Software Framework and evaluated for its prediction accuracy. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

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