Robert S Todd

US Patent:

7383391, Jun 3, 2008

Filed:

May 18, 2005

Appl. No.:

11/131582

Inventors:

Gordon Taylor Davis - Chapel Hill NC, US
Thomas B. Genduso - Apex NC, US
Harold F. Kossman - Rochester MN, US
Robert W. Todd - Raleigh NC, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 9/34
G06F 12/10

US Classification:

711137, 711206

Abstract:

A prefetch mechanism using prefetch attributes is disclosed. In one aspect, an explicit request for data stored in a memory is provided, and a prefetch attribute in a page table entry associated with the explicit request is examined to determine whether to provide one or more prefetch requests based on the prefetch attribute. Another aspect includes determining dynamic prefetch attributes for use in prefetching data, in which prefetch attributes are adjusted based on memory access requests that target next sequential blocks of memory relative to the most recent previous access in a page of memory.

US Patent:

20080155226, Jun 26, 2008

Filed:

Mar 11, 2008

Appl. No.:

12/046345

Inventors:

Gordon Taylor DAVIS - Chapel Hill NC, US
Thomas B. Genduso - Apex NC, US
Harold F. Kossman - Rochester MN, US
Robert W. Todd - Raleigh NC, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 12/10
G06F 12/00

US Classification:

711207, 711213, 711E12059, 711E12061

Abstract:

A prefetch mechanism using prefetch attributes is disclosed. In one aspect, an explicit request for data stored in a memory is provided, and a prefetch attribute in a page table entry associated with the explicit request is examined to determine whether to provide one or more prefetch requests based on the prefetch attribute. Another aspect includes determining dynamic prefetch attributes for use in prefetching data, in which prefetch attributes are adjusted based on memory access requests that target next sequential blocks of memory relative to the most recent previous access in a page of memory.

US Patent:

20140075068, Mar 13, 2014

Filed:

Sep 11, 2012

Appl. No.:

13/609561

Inventors:

David R. Engebretsen - Cannon Falls MN, US
Brian G. Holthaus - Oronoco MN, US
Jonathan L. Kaus - Rochester MN, US
Eric G. Thiemann - Owatonna MN, US
Robert W. Todd - Raleigh NC, US

Assignee:

INTERNATIONAL BUSINESS MACHINES CORPORATION - Armonk NY

International Classification:

G06F 13/42

US Classification:

710106

Abstract:

Techniques are disclosed to perform an operation to facilitate concurrent repair of PCIe switch units in processing environments such as a tightly coupled, multi-switch, multi-adapter, multi-host distributed system. The operation, for an identified switch unit to be repaired, reconfigures all switch unit hardware in the switch fabric by removing all upstream to downstream connections utilizing the identified switch unit. Connections to hosts via the upstream ports are also removed by the operation. Once the switch unit is powered back on, the operation reconfigures all switch unit hardware in the switch fabric by adding all upstream to downstream connections utilizing the identified switch unit. The operation further restores connections to hosts via the upstream ports.

US Patent:

20140075083, Mar 13, 2014

Filed:

Mar 11, 2013

Appl. No.:

13/792957

Inventors:

Brian G. Holthaus - Oronoco MN, US
Jonathan L. Kaus - Rochester MN, US
Eric G. Thiemann - Owatonna MN, US
Robert W. Todd - Raleigh NC, US

Assignee:

INTERNATIONAL BUSINESS MACHINES CORPORATION - Armonk NY

International Classification:

G06F 13/40

US Classification:

710316

Abstract:

Techniques are disclosed to perform an operation to facilitate concurrent repair of PCIe switch units in processing environments such as a tightly coupled, multi-switch, multi-adapter, multi-host distributed system. The operation, for an identified switch unit to be repaired, reconfigures all switch unit hardware in the switch fabric by removing all upstream to downstream connections utilizing the identified switch unit. Connections to hosts via the upstream ports are also removed by the operation. Once the switch unit is powered back on, the operation reconfigures all switch unit hardware in the switch fabric by adding all upstream to downstream connections utilizing the identified switch unit. The operation further restores connections to hosts via the upstream ports.

US Patent:

20150205645, Jul 23, 2015

Filed:

Jan 27, 2014

Appl. No.:

14/164751

Inventors:

- Armonk NY, US
Brian G. HOLTHAUS - Oronoco MN, US
Jonathan L. KAUS - Rochester MN, US
Eric G. THIEMANN - Owatonna MN, US
Scott J. TIMMERMAN - Rochester MN, US
Robert W. TODD - Raleigh NC, US

Assignee:

INTERNATIONAL BUSINESS MACHINES CORPORATION - Armonk NY

International Classification:

G06F 9/52

Abstract:

A management controller in a distributed network switch may operate on sets of ports such that sets of ports containing a same port are processed serially, and sets that do not contain any of the same ports can be processed in parallel. When receiving a set of ports for processing, the management controller organizes the ports into lanes that each correspond to a unique port. If any of the lanes overlap, subsequent port sets are blocked from proceeding until the lanes of preceding port sets are cleared. If no lanes overlap, the sets may be deemed disjoint, and subsequent port sets may be processed in parallel.

US Patent:

20150207694, Jul 23, 2015

Filed:

Jan 20, 2014

Appl. No.:

14/159242

Inventors:

- Armonk NY, US
Brian G. HOLTHAUS - Oronoco MN, US
Jonathan L. KAUS - Rochester MN, US
Eric G. THIEMANN - Owatonna MN, US
Scott J. TIMMERMAN - Rochester MN, US
Robert W. TODD - Raleigh NC, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

H04L 12/24
H04L 29/08

Abstract:

A management controller in a distributed network switch may operate on sets of ports such that sets of ports containing a same port are processed serially, and sets that do not contain any of the same ports can be processed in parallel. When receiving a set of ports for processing, the management controller organizes the ports into lanes that each correspond to a unique port. If any of the lanes overlap, subsequent port sets are blocked from proceeding until the lanes of preceding port sets are cleared. If no lanes overlap, the sets may be deemed disjoint, and subsequent port sets may be processed in parallel.