云存储中的元数据管理方法研究

he single Namenode architecture can't meet the exponentially increased storage demand in cloud computing, and may become a performance bottleneck. This paper presents a metadata management scheme based on HDFS for cloud storage. Our scheme employs multiple Namenodes, and divides the metadata into "buckets" which can be dynamically migrated among Namenodes according to system workloads. To maintain reliability, metadata is replicated in different Namenodes with log replication technology, and Paxos algorithm is adopted to keep replication consensus. Besides, caching and prefetching technology is integrated to improve system performance. Test result shows that our system has a well performance for metadata reading and writing.