Commvault Systems, Inc.
EFFECIENT VERIFICATION OF DATA BLOCKS IN DEDUPLICATED STORAGE SYSTEMS

Abstract:

The exemplary system and methods provide a solution for reclaiming the space occupied by invalid blocks of data stored on secondary storage devices. The space reclamation techniques may employ a primary table, a deduplication chunk table, or an index data structure located with the secondary copy of data on secondary storage devices. One exemplary method uses information from the deduplication database media agent and a deduplication chunk table. Another exemplary method uses an index (e.g., single instance file index) that is associated with and stored with each chunk of data. Based on the information provided by the deduplication chunk table and the index, exemplary system and methods identify blocks of invalid data and copy over only valid data blocks to a new container file.