David M Shackelford

US Patent:

6338114, Jan 8, 2002

Filed:

Aug 18, 1999

Appl. No.:

09/377023

Inventors:

Michael Aloysius Paulsen - late of Morgan Hill CA
David Michael Shackelford - Tucson AZ
John Glenn Thompson - Tucson AZ

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1200

US Classification:

711112, 711154

Abstract:

Disclosed is a method, system, program, and memory for erasing data. A table is provided indicating different groupings of system functions. Each grouping indicates at least one system function. For each grouping there is code to perform erase operations. An erase command to erase data in at least one storage location is received. A determination is then made of the grouping having system functions supported by the system and the table is processed to determine the code for the determined grouping. The code for the determined grouping is executed to perform erase operations with respect to each storage location.

US Patent:

6463501, Oct 8, 2002

Filed:

Oct 21, 1999

Appl. No.:

09/422595

Inventors:

Ronald Maynard Kern - Tucson AZ
Gregory Edward McBride - Tucson AZ
David Michael Shackelford - Tucson AZ

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1216

US Classification:

711100, 711112, 711141, 711162, 711173, 714 6, 714 20, 707201, 707204

Abstract:

A system, method, and program for maintaining data consistency among updates to data storage areas are provided. Each update has an update time the update was made. There are multiple groups of data storage areas. For each group, updates to the data storage area in the group are stored in a journal for storing updates to the group, wherein there are multiple journals. An indication is made in a memory area for each group of a group update time comprising a most recent update time of the updates in the group. The update time for each update in the group is not greater than the group update time. A determination is made of a minimum group update time across all the groups. At least one update is applied to storage if the update time for the update does not exceed the minimum group update time. The data storage areas may be partitioned among a plurality of computer systems, and may be maintained in at least one primary and secondary storage. The data storage areas may also comprise volumes, with each group including at least one volume.

US Patent:

6484187, Nov 19, 2002

Filed:

Apr 28, 2000

Appl. No.:

09/560864

Inventors:

Ronald Maynard Kern - Tucson AZ
Gregory Edward McBride - Tucson AZ
David Michael Shackelford - Tucson AZ

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1730

US Classification:

707204, 707 10, 707200, 707201

Abstract:

A multi-session data storage facility coordinates similar status changes across all sessions at appropriate times. In each session, a data mover implements data mirroring by copying updates from the primary storage to the secondary storage. A master data set, accessible by all sessions, includes a common area for posting commands and/or errors to all sessions and individual session areas for posting errors occurring in particular sessions. When a data mover receives a host initiated command, this data mover becomes a âmaster. â Initially, the master data mover lists the command in the master data sets common area. Whenever other, âslaveâ data movers notice a command in the master data sets common area, they respond by suspending their formation of consistency groups and responding with a âreadyâ message. The âreadyâ message comprises the slave data movers consistency form time (i. e. , the earliest of most-recent update time from all controllers in that session).

US Patent:

6564307, May 13, 2003

Filed:

Aug 18, 1999

Appl. No.:

09/376872

Inventors:

William Frank Micka - Tucson AZ
David Michael Shackelford - Tucson AZ

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1200

US Classification:

711156, 711103, 711170

Abstract:

Disclosed is a method, system, program, and memory for erasing data. A request to erase data at least one storage location is received. In response, a data structure is generated indicating that each storage location subject to the erase request is in an erased state. Upon processing a request to access a storage location, a determination is made as to whether the requested storage location is indicated in the data structure. The data structure is processed to determine whether the requested storage location is in the erased state after determining that the requested storage location is indicated in the data structure. Access to the data at the requested storage location is denied after determining that the requested storage location is in the erased state.

US Patent:

6587933, Jul 1, 2003

Filed:

Jan 26, 2001

Appl. No.:

09/770895

Inventors:

Robert Nelson Crockett - Tucson AZ
William Frank Micka - Tucson AZ
David Michael Shackelford - Tucson AZ

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1200

US Classification:

711154, 711113, 711122, 711162, 711202, 711203, 711 3, 711207, 709100, 710 3

Abstract:

Provided is a method, system, and program for releasing storage space in a first and second storage devices. Updates to the first storage device are copied to the second storage device to provide secondary storage for the updates. A first and second tables map data sets to addresses in the first and second storage devices, respectively. A first command is detected to invalidate data sets in the first table. The addresses in the first table comprise virtual addresses, and a third table provides a mapping of the virtual addresses to physical storage locations in the first storage device. A second command is generated to update the second table to invalidate the data sets in the second storage device invalidated in the first table by the first command. A third command is detected to invalidate the virtual addresses in the third table used by the data sets invalidated in the first table to free the physical storage locations in the first storage device pointed to by the invalidated virtual addresses. A fourth command is generated that is directed to the physical storage locations in the second storage device used by the invalidated data sets.

US Patent:

6611901, Aug 26, 2003

Filed:

Jul 2, 1999

Appl. No.:

09/347344

Inventors:

William Frank Micka - Tucson AZ
Yoram Novick - Haifa, IL
David Michael Shackelford - Tucson AZ

Assignee:

International Business Machines Corporation - New York NY

International Classification:

G06F 1200

US Classification:

711162, 711113, 711202

Abstract:

Disclosed is a method, system, program, and data structures for maintaining electronic data at a point-in-time. A first data structure indicates point-in-time data at one of a first storage location and a corresponding second storage location. A second data structure indicates point-in-time data at one of a first storage location and corresponding second storage location. A first relationship data structure indicates a relationship between the first storage location and corresponding second storage location and a second relationship data structure indicates a relationship between the first storage location and second storage location. A request to process the first storage location is processed by processing the first relationship data structure to determine the corresponding second storage location for the first storage location and processing the first data structure to determine whether data at the first storage location was transferred to the second storage location. A request to process the second storage location is processed by processing the second relationship data structure to determine the corresponding first storage location for the second storage location and processing the second data structure to determine whether the point-in-time data at the first storage location was transferred to the second storage location.

US Patent:

6842825, Jan 11, 2005

Filed:

Aug 7, 2002

Appl. No.:

10/214842

Inventors:

Robert Vaughn Geiner - Raleigh NC, US
Ronald Maynard Kern - Tucson AZ, US
Gregory Edward McBride - Tucson AZ, US
William Frank Micka - Tucson AZ, US
Jeffrey Mark Nick - West Park NY, US
Larry Richard Perry - Gilroy CA, US
David B. Petersen - Great Falls VA, US
David Michael Shackelford - Tucson AZ, US
Harold Glen Slone - Los Gatos CA, US
Harry Morris Yudenfriend - Poughkeepsie NY, US
Douglas M. Zobre - Poughkeepsie NY, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 1200
G06F 1216

US Classification:

711133, 711100, 711118, 711141, 711162, 707201, 707204, 714 6, 713501

Abstract:

In a system including a host, a primary storage subsystem coupled to the host, a cache coupled to the host and separate from the primary storage system, a secondary storage subsystem, and a data mover coupling the primary and secondary storage systems, data is temporarily cached for future storage in the primary storage subsystem so as to preserve timestamp information and maintain data consistency for asynchronously mirroring the data at a secondary subsystem.

US Patent:

7130874, Oct 31, 2006

Filed:

Mar 12, 2002

Appl. No.:

10/096423

Inventors:

Tarek Makansi - Tucson AZ, US
Gregory Edward McBride - Tucson AZ, US
David Michael Shackelford - Tucson AZ, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 17/30

US Classification:

707204, 707 2, 707 10, 707102, 709228, 709229

Abstract:

Provider are a method, system, and program for maintaining data in a distributed computing environment. Data is stored at a primary storage site. A data structure is processed indicating an association of data sets in the stored data, secondary storage sites, and update frequencies. In response to processing the data structure, a determination is made of one of a plurality of secondary storage sites and a determination is made of at least one data set to transmit to the determined secondary storage site at an update frequency. The determined data set is transmitted to the determined secondary storage site according to the update frequency.