A snapshot-based fine granularity versioning technique is presented to retain history data only for a single directory or a single file, and bring flexibility to multi-version file systems. Adopting the strategy to search inname space and version space separately, this paper also presents backward inheriting path-finding mechanism inversion space. This mechanism is beneficial to the performance and management, because it can utilize the couplingrelationship between versions to optimize the data layout of versions and build hierarchy in version space toaccelerate the path-finding procedure. In addition, fast index structures for directory versions and file versions aredesigned. This prototype file system——THVFS can achieve both good performance and high availability withthese technologies mentioned above. The experimental results show that the average time of searching old versions in THVFS was reduced by 34.4% than in ext3cow, the famous multi-version file system. In the trace experiment, theaverage read response time in THVFS was 12% less than in ext3, and only 80% extra space was needed to retain allhistory data when snapshots are taken every 72 minutes in THVFS.