Abstract: A method, apparatus, and article of manufacture for optimizing the retrieval of blocks of data from a tape media of a longitudinal serpentine tape drive. A device block map (DBM) is retrieved from the tape media and stored in memory. The DBM comprises a table having one or more rows and one or more columns for each block of data stored on the tape media. The columns are selected from a group comprising a wrap column, a position column, a logical block number column, and a file identifier column, wherein the wrap column indicates a track where the block of data is recorded on the tape media, the position column indicates a physical position where the block of data is recorded on the tape media, the logical block number column indicates a logical block number for the block of data, and a file identifier column indicates a logical file identifier for the block of data.

Abstract: A data storage system for use with a tape cartridge storing data in a serpentine pattern on tape media, and having a memory device for storing a device block map for the tape median, comprises tape drive, or a loading mechanism, which first positions the tape cartridge at memory interface for transfering the device block map from the memory device to a processor, and subsequently positions the tape media for reading and/or writing. The processor processes the device block map from the memory device for optimal retrieval of the serpentine pattern data of the tape media. The processing of the device block map occurs while the tape media is positioned for reading and/or writing, so that the processor begins the retrieval reading process immediately upon the positioning of the tape media. In another aspect of the invention, a robotic accessor of an automated data storage library moves the tape cartridge to the tape drive.

Abstract: A computer media tape cartridge has a multiple volume selector switch with a plurality of positions which allow a user to physically segment the tape into a corresponding number of sections for more efficient use of the tape. By moving the switch to a desired position, the user may select and use the tracks in one or all of the positions on the tape. These positions include an "all position" wherein the tape is a single volume for reading and writing data, and individual positions wherein only the selected position is available for reading or writing data to the tape. Using the cartridge in the latter manner physically segments tape into four separate volumes. The cartridge is used in a tape drive having a plurality of sensors for detecting the position of the switch.

Abstract: Various data storage formats help to efficiently locate, read, and write user data stored on magnetic tape media. A tape is formatted by writing multiple segment-headers, free from any interleaved access of user data Adjacent segment-headers are spaced by a predetermined interval to define multiple data storage segments. Segment-headers all contain a unique key, which is copied into a key index to identify valid segments. After formatting, normal tape accesses can be performed. Without erasing any old headers or data, a new formatting scheme can be established by writing new segment-headers on the tape. The new segment-headers include a new unique key, replacing the previous key in the key index. Previous segment-headers stored on the tape are ignored, since they lack the updated key. Segments may be selectively grouped to provide independently addressable partitions. Mapping between segments and partitions can use a fixed relationship (e.g.

Abstract: A storage media for linear, serpentine recording is pre-formatted for data storage operations by recording partition format information in a single pass along the length of the storage media by recording partition format information for all storage media tracks at regular partition intervals defined by index locations alternately in both storage media directions before moving the storage media to the next partition interval. At each index location, partition markers are recorded in successive parallel tracks first in one media direction and then the other until markers are recorded across the entire width of the storage media. The steps of moving to a next partition index location, recording partition information in successive parallel tracks in first one direction and then the other, and moving to a next index location one partition length away, are repeated until all partitions of the storage media are pre-formatted.