US Patent 9501487 Change tree incremental backup

Implementations are provided herein for incremental backup using a change tree. A change tree is a database file for tracking file system changes of a specific dataset, such as a directory of a file system. A backup process can create and/or initiate a change tree when creating a backup snapshot of a dataset. After the change tree is created, all file system changes inside the dataset can be tracked. The next incremental backup can then take advantage of the change tree to backup changes without traversing the entire dataset. Thus, incremental backups can be more efficient and are better able to keep up with tape streaming speed.