Consolidating snapshots in a continuous data protection system using journaling

摘要

In one aspect, a method of consolidating snapshots includes storing snapshots using a journal in a continuous data protection environment. Each entry of the journal corresponds to one of a unique group of DO METADATA stream data blocks and a unique group of UNDO METADATA stream data blocks. The method also includes receiving a user input designating at least two snapshots to consolidate, storing changes to the data blocks from the at least two snapshots in a temporary stream on the journal and consolidating the at least two snapshots by replacing the at least two snapshots in the journal with a single consolidated snapshot comprising the changes for each data block from the temporary stream. Storing changes includes storing one of the oldest changes of the UNDO METADATA stream data blocks and the latest changes of the DO METADATA stream data blocks.