一种基于可用性的动态云数据副本管理机制

摘要

副本是提高云存储数据可用性的关键技术之一.为提供低成本高效益的可用性,并提高云存储的性能和负载均衡,本文提出一种动态副本管理机制DRM(Dynamic Replica Management scheme).DRM研究确定数据可用性和副本数之间的关系模型,并利用此模型来动态计算和维护给定可用性要求的最小副本数,并基于节点性能和用户访问特性确定副本放置位置.根据节点规模变化,DRM动态调整副本数量以确保数据可用性需求.DRM 在节省资源成本的前提下,提高了云存储的性能和负载平衡.本文在HDFS(Hadoop Distributed File System)上实现了DRM,实验结果表明DRM在成本、负载平衡和性能都优于现有HDFS副本管理机制.%Data replication has been widely used to improve the data availability of large cloud storage systems.To provide cost-effec-tive availability and improve cloud storage performance and load balancing,this paper proposes a dynamic replica management scheme called DRM.The DRM study determines the relationship model between data availability and number of replicas and uses this model to dynamically calculate and maintain the minimum number of replicas for a given availability requirement and to determine the loca-tion of replicas based on node performance and user access characteristics.Depending on the change of the node size,DRM dynamical-ly adjusts the number of replicas to ensure data availability requirements.DRM improves the performance and load balance of cloud storage under the premise of saving resource cost.DRM is implemented on HDFS (Hadoop Distributed File System),and the results show that DRM is superior to the default replication-managed HDFS in terms of cost,load balancing,and performance.