Patent ID: 7519634

Claim:
A system to preserve memory resources during data backup, comprising: a computer having memory and a hard disk, the computer storing local files on the hard disk; a server storing backup files corresponding to a prior backup of the local files; a generation module to access the server and generate an unordered list of the backup files and associated attributes from the server, the attributes comprising file name, creation date, creation time, modification date, modification time, file size, access control lists, and checksums of relative data streams; and a processing module to back up, one at a time, the local files of the list by modifying the backup files to reflect changes to the local files, the processing module comprising: a retrieval module to retrieve, from the hard disk, local file attributes corresponding to a local file; a comparator module to compare the local file attributes to corresponding backup file information on the list to identify differences between the local file and a corresponding backup file; an update module to update the corresponding backup file to reflect the differences; a marcation module to mark the list to indicate a match between the corresponding backup file information and the local file attributes; and an expiration module to expire unmarked backup files from the server.