Patent ID: 6874072

Claim:
A method for managing a reusable linear access storage medium having a plurality of linearly ordered media blocks, where a media block is included in a media set if the media block is used to store at least a portion of one or more linearly ordered data blocks, the method comprising: creating an active window table to monitor the at least one media block in the media set, the active window table containing a list of media blocks in the media set, an identification of data blocks stored in the listed media blocks, information regarding expiration of data blocks stored in the listed media blocks, and an indication, separate from the expiration information, of a reference media block that is the oldest media block in the list; identifying any media blocks listed in the active window table that store only data blocks that have become expired, based on the information contained in the active window table; removing any identified media blocks from the active window table; determining whether any of the identified media blocks is a reference media block; and updating, if any of the identified media blocks removed is determined to be a reference media block, the active window table to indicate a dIfferent media block as a reference media block that is the oldest media block of the remaining media blocks listed in the active window table.