Seagate Technology Incorporated

Seagate Technologies, Inc.

Seagate Tech. LLC

Edward Sean Hoskins

Steven Scott Williams

Stanton MacDonough Keeler

Robert Warren

Daniel Scott Fisher

Ewe Chye Tan

Mike Propps

Francis T Seuberling

A method and device for mapping an inherently defective sectors or newly-identified defective sectors in a disc drive to a good sector in the disc drive in such a way that data fragmentation is minimized and that speed efficiency in accessing the data stored in the disc drive is improved due to minimized seek time and latency delays. In a disc drive data storage area of sectors, user spare sectors are located not at the end of a track, a cylinder, or a segment but at the end of the data storage area. Any defective user data sector is slipped to the next closest good sector over the full volume of the data storage area. That is, the data that would have been stored in the defective sector is pushed down to the next good sector, as each of the subsequent sectors are slipped sequentially to the next good sector in the full volume of the data storage area. A user sector slip list is generated to access the full volume slipped data storage area. Newly-identified defective sectors are redirected to good sectors in reserve data area in the data storage area of sectors. An alternate sector list is maintained to facilitate an access to a redirected reserve data area.

Full volume slip defect management in a disc drive

Optimal command nodes are selected in a computing device having multiple command node queues by a method which identifies a command node in a first queue and determines if the identified command node collides with a command node in a second queue. If a collision between the identified command node and a command node in the second queue is determined, the collision is corrected and the identified command node then may be moved into the second queue. The second queue is then sorted according to a predetermined routine to select the optimal command node.

Command queue processor

A skip mask mechanism is implemented in a disc drive in order to increase performance by minimizing the number of necessary disc rotations required while executing a set of pseudo-sequential commands. The drive includes an interface between the host computer and the drive, a read/write channel between the interface and the transducer/head, a formatter between the interface and the read/write channel for timing when data is transferred between the interface and the read/write channel, and a skip mask mechanism interposed between a target calculator and the formatter that provides a masked input to the formatter for controlling passage of data between the interface and the read/write channel.

Method and apparatus for optimizing skip mask operations in a disc drive

A procedure for reading data stored on a data storage disc in a disc drive is disclosed. The procedure involves reading data from one or more sectors on the data storage disc after an error occurred while initially reading the sector(s) pursuant to a read command issued by a host computer. During the initial read, the procedure logs information pertaining to the sector(s) on the disc where an error occurred. The logged information is then used during the procedure to retrieve data from the sector(s) in a single revolution of the disc. The procedure uses a skip mask, a vector buffer management list and a data throttling mechanism to administer a transfer of data from a disc to a host computer via a data buffer.

Method and apparatus for read error recovery

A read-on-arrival scheme for reading data stored on a track of a data storage disc is disclosed. The track is divided into a plurality of sequentially arranged data sectors. Each data sector stores a block of data. A host computer issues a read command requesting retrieval of a segment of data blocks stored on a plurality of the data sectors. The segment may include a target data segment as well as a pre-fetch and post-fetch data segment. The read command specifies a target sector that a transducer is to initially access on the track. Upon receipt of the read command, components of a disc drive move the transducer to the track for access of the segment requested in the command. The disc drive components enable the transfer of data regardless of whether the transducer first accesses a sector located in sequential order prior to or following the target sector.

Read on arrival scheme for a disc drive

A data storage device control module for controlling operational processes in a data storage device comprises a number of preemptive modules, a number of non-preemptive modules, and a scheduler module operable to schedule the execution of the non-preemptive modules only in the data storage device control module. Preferably included as one of the non-preemptive modules is a queue processor module operable to manage the position and movement of command nodes in multiple command node queues.

Modular disc drive architecture

A disc drive includes a base and a disc rotatably attached to the base. A controller for a disc drive uses a system for mapping logical block addresses to actual location on a disc drive stores the number of skipped or defective sectors which occur prior to a target cylinder in a cylinder skip table. The system estimates a starting cylinder location for the selected logical block address. After estimating the cylinder location, a number of skipped defective sectors that have occurred prior to a cylinder start is determined. The starting location of the cylinder is slipped by this amount. A target track and associated head is also determined. Information in the track identification field is used to adjust the actual location on the track and to determine if a track seek to another track is needed.

Full slip defect management system using track identification

A method and system for determining data sector splits across servo bursts in a disc drive having a data disc with an embedded servo configuration. The disc drive includes a data transducer selectively positionable over the data disc for transferring data to and from the data disc, and the data disc includes a plurality of zones of predefined tracks. The method includes locating one or more frame table parameters based on a new zone position, creating a plurality of new frame table entries, while the disc drive is in operation, based on the frame table parameters, and moving the data transducer from a past zone position to the new zone position. The disc drive includes parameter memory and frame table memory. The parameter memory contains a plurality of zone records, with the zone records containing a plurality of zone table parameters. The frame table memory is utilized to store a frame table. A frame table generator is coupled with the parameter memory and the frame table memory and is configured to create a new frame table in the frame table memory when the data transducer is required to move to a new zone position.

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Longmont, CO, United States of America

Edward Sean Hoskins