A hybrid approach to optimistic file system directory tree synchronization
Tancred Lindholm, Jaakko Kangasharju, Sasu Tarkoma · 2005
There are two main approaches to optimistic file system synchronization: distributed file systems and file synchronizers. The former type is characterized by a log-based approach that depends on access to file system internals, the latter by a state-based approach that utilizes the standard file system interface, which limits the efficiency of change detection.We propose a hybrid approach that 1) defines a minor extension to the semantics of the file system interface that enables efficient state-based file system change detection and 2) employs selectively instantiated XML documents to make the use of state-based algorithms for optimistic synchronization feasible on large file systems.The hybrid approach is simple, well-suited for current file system architectures, and allows us to leverage existing state-based reconciliation algorithms. An initial implementation shows our approach to be feasible, lightweight, and interoperable and to have satisfactory performance.