Method and apparatus for implementing a highly efficient, robust modified files list (MFL) for a storage system volume

摘要

When a volume is created, a Modified Files List (MFL) is established and an epoch timestamp, identifying an important point in time, is set for the volume. Entries are inserted into the MFL whenever files are first added to or changed on the volume. Entries are flagged with the epoch timestamp in which they are added to the MFL. Entries are removed from the MFL when files are restored to an already-archived condition or are deleted from the volume. A system administrator can declare a new epoch at any time, and will declare a new epoch before performing a backup. The system administrator will select an epoch for backup purposes. The files inserted into the MFL before the selected epoch timestamp are enumerated and archived using a backup tool. After the backup tool turns off a file's data and metadata archive bits, the corresponding entry is removed from the MFL.