Research On Key Issues Of Scalable Distributed File System Metadata Service In Large-scale Networked Storage Systems

Efficiency of metadata access is a key factor of that of file access. In large-scale networked storage systems, with increase of file system metadata requests, doing research on key issues of scalable file system metadata service becomes a key problem of distributed file system researches.Based on characteristics of locality, dynamicity and rare cross-server requests of active metadata, a dynamically scalable distributed file system metadata service is provided which includes:a) A symmetric architecture of metadata servers which bases on fully shared virtual storage model and hierarchical storage resource management which supports scalable storage resource management.b) Flexible management of file system metadata requests distribution. Supported by hierarchical distribution management, flexible metadata requests distribution which keeps metadata locality in mind decides requests distribution dynamically, which supports dynamic changes in system.And more, there is a lightweight protocol for atomicity of cross-server metadata requests. Based on the symmetric architecture and fully shared storage model, requests which involve metadata distributed on multiple servers will be processed on single server by migrating active metadata between servers.Evaluations on the prototype verify its scalability. And it also points out future works on architecture adjustment, adaptive metadata requests distribution, performance tuning and high-available metadata service, and so on.