Patent ID: 6920447

Claim:
A method of recalling data objects stored on a plurality of media comprising: receiving a plurality of requests to recall data objects, each data object being located on a particular one of said plurality of media; creating a plurality of queues, wherein each one of said queues corresponds to one of said media; placing said requests on the created queues, wherein each request is placed on the queue corresponding to the medium on which the requested data object is located; activating a first of said queues, said first queue being associated with a first of said plurality of media; and retrieving, from said first medium, the data objects requested on the first queue, wherein each queued request indicates the offset from a predetermined location on a medium at which the requested data object is located, and wherein said placing act comprises: organizing the requests on each queue in a first and a second sequence, each sequence comprising a set of requests whose offsets are monotonically increasing within the respective sequence, and wherein the act of creating a plurality of queues comprises timestamping each of the created queues, and wherein the act of activating a first of said plurality of queues comprises selecting a queue to be activated based on the timestamps of the respective queues.