Seagate Technology Incorporated

Hewlett-packard Development Company, L.P.

Compaq Computer Corporation, Inc.

Kenneth Hoffman Bates

Clark Edward Lubbers

Susan Gaye Elkington

John Franklin Mertz

Bradford Scott Morgan

Mark A Gaertner

James S Jackson

James Perry Jackson

Gabriel J Lawson

A method and apparatus associated with transferring data from a remote device to a recipient device having a first memory space and a second memory space. The method includes issuing a transfer command from the remote device to request transferring a set of data to the second memory space; temporarily storing the set of data in the first memory space pending a transfer to the second memory space; and appending the set of data to other sequential data in the first memory to obtain a transfer data block of a predetermined size for transfer to the second memory space. A corresponding apparatus is provided comprising circuitry configured to buffer write commands by characterizing each write command as being either a sequential write or a random write, and responsively appending data associated with sequential write commands in order to obtain a transfer block of a predetermined size.

Write caching random data and sequential data simultaneously

A data storage system is provided with command queue controller circuitry for positionally pushing pending access commands from a command queue to a selected target zone of a storage space. A method is provided for dividing a storage space into a plurality of LBA zones, selecting a target zone in relation to a number of pending access commands for each of the plurality of LBA zones, and pushing access commands to the target zone.

Command queue ordering by positionally pushing access commands

In a data storage system a number of records are prefetched from large volume storage devices for transfer to a cache in order to return requested records to a host computer in response to a read request from the host computer. If a previous prefetch is not complete when the read request is received, the number of records in a next prefetch of records is increased by a preset amount. If a previous prefetch is complete, a next prefetch of records is initiated with the same number of records in the prefetch as the previous prefetch. The initiation of prefetch operations is triggered by detection of a sequential read stream in a plurality of read requests from the host computer. When the prefetch size is increased, the preset amount of the increase equals the number of records in the read request from the host computer. After requested records are returned from the cache to the host computer in response to the read request, storage space in the cache used by the returned requested records is released.

Maximizing sequential read streams while minimizing the impact on cache and other applications

Growing community of inventors

Colorado Springs, CO, United States of America

Kenneth Hoffman Bates