Cloud computing is becoming a very popular word in industry and is receiving a large amount of atten- tion from the research community. Replica management is one of the most important issues in the cloud, which can of...Cloud computing is becoming a very popular word in industry and is receiving a large amount of atten- tion from the research community. Replica management is one of the most important issues in the cloud, which can offer fast data access time, high data availability and reliability. By keeping all replicas active, the replicas may enhance system task successful execution rate if the replicas and requests are reasonably distributed. However, appropriate replica place- ment in a large-scale, dynamically scalable and totally vir- tualized data centers is much more complicated. To provide cost-effective availability, minimize the response time of ap- plications and make load balancing for cloud storage, a new replica placement is proposed. The replica placement is based on five important parameters： mean service time, failure probability, load variance, latency and storage usage. How- ever, replication should be used wisely because the storage size of each site is limited. Thus, the site must keep only the important replicas. We also present a new replica replacement strategy based on the availability of the file, the last time the replica was requested, number of access, and size of replica. We evaluate our algorithm using the CloudSim simulator and find that it offers better performance in comparison with other algorithms in terms of mean response time, effective network usage, load balancing, replication frequency, and storage usage展开更多
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
文摘Cloud computing is becoming a very popular word in industry and is receiving a large amount of atten- tion from the research community. Replica management is one of the most important issues in the cloud, which can offer fast data access time, high data availability and reliability. By keeping all replicas active, the replicas may enhance system task successful execution rate if the replicas and requests are reasonably distributed. However, appropriate replica place- ment in a large-scale, dynamically scalable and totally vir- tualized data centers is much more complicated. To provide cost-effective availability, minimize the response time of ap- plications and make load balancing for cloud storage, a new replica placement is proposed. The replica placement is based on five important parameters： mean service time, failure probability, load variance, latency and storage usage. How- ever, replication should be used wisely because the storage size of each site is limited. Thus, the site must keep only the important replicas. We also present a new replica replacement strategy based on the availability of the file, the last time the replica was requested, number of access, and size of replica. We evaluate our algorithm using the CloudSim simulator and find that it offers better performance in comparison with other algorithms in terms of mean response time, effective network usage, load balancing, replication frequency, and storage usage
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.
