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Online Layered File System (OLFS): A Layered and Versioned Filesystem and Performance Analysis
Proceedings of Electro/Information Technology
  • Joseph P. Kaylor
  • Konstantin Läufer, Loyola University Chicago
  • George K. Thiruvathukal, Loyola University Chicago
Document Type
Conference Proceeding
Publication Date
Publisher Name
IEEE Computer Society
We present a novel form of intra-volume directory layering with hierarchical, inheritance-like namespace unification. While each layer of an OLFS volume constitutes a subvolume that can be mounted separately in a fan-in configuration, the entire hierarchy is always accessible (online) and fully navigable through any mounted layer. OLFS uses a relational database to store its layering metadata and either a relational database or any (virtual) host file system as its backing store, along with metadata and block caching for improved performance. Because OLFS runs as a virtual file system in user-space, its capabilities are available to all existing software without modification or special privileges. We have developed a reference implementation of OLFS for FUSE based on MySQL and XFS, and conducted performance benchmarking against XFS by itself. We explore several applications of OLFS, such as enhanced server synchronization, transactional file operations, and versioning.
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Creative Commons Attribution-Noncommercial-No Derivative Works 3.0
Citation Information
Joe Kaylor, Konstantin Läufer, and George K. Thiruvathukal, Online Layered File System (OLFS): A layered and versioned filesystem and performance analysi, In Proceedings of Electro/Information Technology 2010 (EIT 2010).