针对云计算系统中的单点失效问题,提出一种云计算环境下的动态数据副本管理策略.该管理策略通过综合考虑目标放置节点的当前负载状况、可用存储空间大小、通信带宽以及其历史访问记录和历史失效记录等状态参数来进行数据文件的副本放置决策,并在进行副本置换操作时给予大尺寸数据文件副本更高的优先权.测试结果表明:该管理策略具有较为稳定的平均数据访问距离,且在云计算系统的负载均衡水平和平均任务执行时间指标上优于另外几种经典的副本策略. Aiming at the single-point failure problem in cloud computing system, this paper proposes a dynamic data copy management strategy in cloud computing environment by considering the current load status, available storage space, communication bandwidth and its historical access Records and historical failure records and other state parameters to make a copy of the data file placement decisions, and give a higher priority in the copy replacement operation of a larger copy of the data file.The test results show that the management strategy has a more stable average data access Distance, and cloud computing system load balancing level and the average task execution time index better than the other several classic copy strategy.