公开(公告)号：DE69328853D1

公开(公告)日：2000-07-20

申请号：DE69328853

申请日：1993-09-13

Applicant: IBM

Inventor： CANDELARIA SUSAN KAY ,  HANSON DEAN LEE ,  KWOK ROBERT LAM ,  LANE KENNETH WAYNE ,  NORDAHL DONALD MARVIN ,  REID MARK ALBERT ,  SHERMAN II WILLIAM GRISWOLD

IPC: G06F3/06 ,  G11B19/00 ,  G11B19/02 ,  G11B27/00

Abstract: A method and system for enhancing efficiency of data accessing within a storage subsystem, preferably including a DASD with multiple disks, which is coupled to a host system via a storage subsystem controller. Recording tracks are accessed utilizing multiple switchable transducer heads. A signal transmitted from the host system is utilized to define a transducer head switching table within the storage subsystem controller listing each track to be accessed and an associated control parameter for selecting a particular transducer head to be utilized to access a subsequent track. Each time the end of an accessed track is encountered, this table is accessed and the control parameter associated with that track is accessed and coupled to the DASD in order to select a subsequent track for access. A pointer is established into this table at the listing of an initially accessed track and access may be terminated when that pointer is encountered.

公开(公告)号：DE69327892D1

公开(公告)日：2000-03-30

申请号：DE69327892

申请日：1993-08-25

Applicant: IBM

Inventor： BEARDSLEY BRENT CAMERON ,  BENHASE MICHAEL THOMAS ,  BLOUNT LAWRENCE CARTER ,  CANDELARIA SUSAN KAY ,  HYDE JOSEPH SMITH

IPC: G06F3/06 ,  G06F13/12

Abstract: A storage system controller, coupled to one or more host computers via multiple communication channels, is utilized to control access to one or more direct access storage devices. A host computer authorizes the storage system controller to search within a range of data locations within the storage system, sets an initial location from which the data search will begin, and specifies a key field argument to search for. The host computer then permits the storage system controller to independently search the authorized range of data locations within the storage system or within cache memory within the storage system controller. The storage system controller examines multiple records within the authorized range of data locations to locate a desired record associated with the key field argument and presents a status report to the host computer only after the desired record is located or the entire range of data is searched and the desired record was not located.