公开(公告)号：DE69714324D1

公开(公告)日：2002-09-05

申请号：DE69714324

申请日：1997-03-06

Applicant: IBM

Inventor： BASHAM ROBERT BEVERLY ,  DAHMAN KIRBY GRANT ,  FRY SCOTT MILTON ,  JOHNSON STEVEN DOUGLAS ,  WILSON STEVEN BENNETT

IPC: G11B5/008 ,  G11B5/584 ,  G11B15/087 ,  G11B20/12 ,  G11B27/10 ,  G11B27/32

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. one-to-one), or each partition may be variably sized according to the amount of data to be stored therein. Variable-sized partitions may be automatically padded with a selected number of empty segments. Another feature is flexible-capacity scaling, which distributes an ordered set of device blocks on a multi-track magnetic tape medium. The device blocks are bi-directionally stored in a continuous configuration of multiple adjacent stacked serpentine patterns occupying some or all of the tape. This configuration permits sequential access of all device blocks without advancing the tape medium to skip over regions between adjacent device blocks.

公开(公告)号：SG77701A1

公开(公告)日：2001-01-16

申请号：SG1999003663

申请日：1999-07-29

Applicant: IBM

Inventor： FRY SCOTT MILTON ,  WILSON STEVEN BENNETT ,  JOHNSON STEVEN DOUGLAS

IPC: G11B27/10 ,  G11B15/00 ,  G11B15/07 ,  G11B15/18 ,  G11B15/675 ,  G11B15/68 ,  G11B23/04 ,  G11B23/087 ,  G11B23/107 ,  G11B27/00 ,  G11B27/11 ,  G06F12/00

Abstract: Disclosed is 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 media. A tape drive, or a loading mechanism, first positions the tape cartridge at memory interface for transferring 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. The tape cartridge is positioned at the memory interface on the robotic accessor, and the stored device block map is transferred from the memory device to the processor, during the move.