The Versioning System Balancing Data Amount and Access Frequency on Distributed Storage System

In this paper, a method of balancing both access fre-quency and data amount for a distributed parallel storage system under version management is discussed. We assume the version management method keeps the latest version of file and a number of differential information sets to access previous versions. Since the access frequency for an aged version is tend to be lower than that for the latest version, we control the access frequency distribution by the place-ment of the latest versions, while the data amount distribu-tion is managed by the placement of the differential infor-mation whose size is enough small to adjust the subtle dif-ference of data amount. We propose a distributed directory structure and data placement algorithm, and evaluate its ef-fect on the access frequency and data amount distribution. 1