In recent years, with the rapid development of data intensive applications, data replication has become an enabling technology for the data grid to improve data availability, and reduce file transfer time and bandwidt...In recent years, with the rapid development of data intensive applications, data replication has become an enabling technology for the data grid to improve data availability, and reduce file transfer time and bandwidth consumption. The placement of replicas has been proven to be the most difficult problem that must be solved to realize the process of data replication. This paper addresses the quality of service （QoS） aware replica placement problem in data grid, and proposes a dynamic programming based replica placement algorithm that not only has a QoS requirement guarantee, but also can minimize the overall replication cost, including storage cost and communication cost. By simulation, experiments show that the replica placement algorithm outperforms an existing popular replica placement technique in data grid.展开更多
As the amount of data continues to grow rapidly,the variety of data produced by applications is becoming more affluent than ever.Cloud computing is the best technology evolving today to provide multi-services for the ...As the amount of data continues to grow rapidly,the variety of data produced by applications is becoming more affluent than ever.Cloud computing is the best technology evolving today to provide multi-services for the mass and variety of data.The cloud computing features are capable of processing,managing,and storing all sorts of data.Although data is stored in many high-end nodes,either in the same data centers or across many data centers in cloud,performance issues are still inevitable.The cloud replication strategy is one of best solutions to address risk of performance degradation in the cloud environment.The real challenge here is developing the right data replication strategy with minimal data movement that guarantees efficient network usage,low fault tolerance,and minimal replication frequency.The key problem discussed in this research is inefficient network usage discovered during selecting a suitable data center to store replica copies induced by inadequate data center selection criteria.Hence,to mitigate the issue,we proposed Replication Strategy with a comprehensive Data Center Selection Method(RS-DCSM),which can determine the appropriate data center to place replicas by considering three key factors:Popularity,space availability,and centrality.The proposed RS-DCSM was simulated using CloudSim and the results proved that data movement between data centers is significantly reduced by 14%reduction in overall replication frequency and 20%decrement in network usage,which outperformed the current replication strategy,known as Dynamic Popularity aware Replication Strategy(DPRS)algorithm.展开更多
数据复制技术广泛用于数据网格,如何合理地放置复制时产生的数据副本来更有效地提高数据访问性能成为一个值得研究的重要问题。本文针对无向连通图表示的数据网格模型,提出了一种满足各用户服务质量(quality of service,QoS)需求的副本...数据复制技术广泛用于数据网格,如何合理地放置复制时产生的数据副本来更有效地提高数据访问性能成为一个值得研究的重要问题。本文针对无向连通图表示的数据网格模型,提出了一种满足各用户服务质量(quality of service,QoS)需求的副本放置算法(replica placement algorithm,RPA),通过该QoS感知的副本放置算法能够获得k个副本放置位置,并且使得整个数据网格系统的通信代价最小。最后,文章通过相应的仿真实验证明了该算法的可靠性和有效性。展开更多
云计算作为一种新的商业计算模型,提供了弹性计算和存储资源等服务.云计算具有超大规模、高可扩展性、高可靠性、虚拟化、按需服务和价格低廉等特点,许多用户把应用提交到云环境下运行.随着越来越多的数据密集型应用部署到云计算环境上...云计算作为一种新的商业计算模型,提供了弹性计算和存储资源等服务.云计算具有超大规模、高可扩展性、高可靠性、虚拟化、按需服务和价格低廉等特点,许多用户把应用提交到云环境下运行.随着越来越多的数据密集型应用部署到云计算环境上运行,应用会有不同的QoS要求.为了保证在放置应用数据副本时,数据副本都能满足应用的QoS要求,我们需要考虑云计算环境下QoS约束的应用数据副本放置问题,为此提出一种QoS感知的副本放置算法(QoS-Aware Replica Placement with PSO,QRPPSO),该算法首先对QoS约束集的属性进行量化,然后构建目标优化模型,最后在副本放置优化算法引入粒子群优化来决定副本放置位置.仿真实验结果表明所提策略能有效解决QoS约束的应用数据副本放置问题.展开更多
基金sponsored by the National Natural Science Foundation of China (61202354)the Hi-Tech Research and Development Program of China (2007AA01Z404)Scientific & Technological Support Project (Industry) of Jiangsu Province (BE2011189)
文摘In recent years, with the rapid development of data intensive applications, data replication has become an enabling technology for the data grid to improve data availability, and reduce file transfer time and bandwidth consumption. The placement of replicas has been proven to be the most difficult problem that must be solved to realize the process of data replication. This paper addresses the quality of service （QoS） aware replica placement problem in data grid, and proposes a dynamic programming based replica placement algorithm that not only has a QoS requirement guarantee, but also can minimize the overall replication cost, including storage cost and communication cost. By simulation, experiments show that the replica placement algorithm outperforms an existing popular replica placement technique in data grid.
基金supported by Universiti Putra Malaysia and the Ministry of Education(MOE).
文摘As the amount of data continues to grow rapidly,the variety of data produced by applications is becoming more affluent than ever.Cloud computing is the best technology evolving today to provide multi-services for the mass and variety of data.The cloud computing features are capable of processing,managing,and storing all sorts of data.Although data is stored in many high-end nodes,either in the same data centers or across many data centers in cloud,performance issues are still inevitable.The cloud replication strategy is one of best solutions to address risk of performance degradation in the cloud environment.The real challenge here is developing the right data replication strategy with minimal data movement that guarantees efficient network usage,low fault tolerance,and minimal replication frequency.The key problem discussed in this research is inefficient network usage discovered during selecting a suitable data center to store replica copies induced by inadequate data center selection criteria.Hence,to mitigate the issue,we proposed Replication Strategy with a comprehensive Data Center Selection Method(RS-DCSM),which can determine the appropriate data center to place replicas by considering three key factors:Popularity,space availability,and centrality.The proposed RS-DCSM was simulated using CloudSim and the results proved that data movement between data centers is significantly reduced by 14%reduction in overall replication frequency and 20%decrement in network usage,which outperformed the current replication strategy,known as Dynamic Popularity aware Replication Strategy(DPRS)algorithm.
文摘数据复制技术广泛用于数据网格,如何合理地放置复制时产生的数据副本来更有效地提高数据访问性能成为一个值得研究的重要问题。本文针对无向连通图表示的数据网格模型,提出了一种满足各用户服务质量(quality of service,QoS)需求的副本放置算法(replica placement algorithm,RPA),通过该QoS感知的副本放置算法能够获得k个副本放置位置,并且使得整个数据网格系统的通信代价最小。最后,文章通过相应的仿真实验证明了该算法的可靠性和有效性。
文摘云计算作为一种新的商业计算模型,提供了弹性计算和存储资源等服务.云计算具有超大规模、高可扩展性、高可靠性、虚拟化、按需服务和价格低廉等特点,许多用户把应用提交到云环境下运行.随着越来越多的数据密集型应用部署到云计算环境上运行,应用会有不同的QoS要求.为了保证在放置应用数据副本时,数据副本都能满足应用的QoS要求,我们需要考虑云计算环境下QoS约束的应用数据副本放置问题,为此提出一种QoS感知的副本放置算法(QoS-Aware Replica Placement with PSO,QRPPSO),该算法首先对QoS约束集的属性进行量化,然后构建目标优化模型,最后在副本放置优化算法引入粒子群优化来决定副本放置位置.仿真实验结果表明所提策略能有效解决QoS约束的应用数据副本放置问题.
