File System Support for Delta Compression

Abstract

Delta compression, which consists of compactly encoding one file version as the result of changes to another, can improve efficiency in the use of network and disk resources. Delta compression techniques are readily available and can result in compression factors of five to ten on typical data, however managing delta-compressed storage is difficult. I present a system that attempts to isolate the complexity of deltacompressed storage management by separating the task of version labeling from performance issues. I show how the system integrates delta-compressed transport with delta-compressed storage. Existing tool