Patents by Inventor Christopher M. Dennett

Christopher M. Dennett has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11372555
    Abstract: A method and system may reconstruct data in a smart storage array where upon detection of data inconsistency, an application of the system is notified and affected data strips are rebuilt. When an initiator detects stripe corruption, the initiator may report the strip corruption to storage. The storage may lock the strip for I/O operations. Initiators may determine recovery scenarios for rebuilding the data strips and send the scenarios to storage. At storage, initiator replies may be collected, and a rebuild option with the highest votes may be automatically determined for a reconstruction operation. Once the reconstruction operation is completed, the rebuilt stripe may be unlocked and data operations may recommence.
    Type: Grant
    Filed: January 23, 2020
    Date of Patent: June 28, 2022
    Assignee: International Business Machines Corporation
    Inventors: Asaf Porat-Stoler, Constantine Gavrilov, Christopher M. Dennett, Rivka Mayraz Matosevich, Sergey Marenkov, Jonathan Fischer-Toubol, Afief Halumi
  • Publication number: 20210232324
    Abstract: A method and system may reconstruct data in a smart storage array where upon detection of data inconsistency, an application of the system is notified and affected data strips are rebuilt. When an initiator detects stripe corruption, the initiator may report the strip corruption to storage. The storage may lock the strip for I/O operations. Initiators may determine recovery scenarios for rebuilding the data strips and send the scenarios to storage. At storage, initiator replies may be collected, and a rebuild option with the highest votes may be automatically determined for a reconstruction operation. Once the reconstruction operation is completed, the rebuilt stripe may be unlocked and data operations may recommence.
    Type: Application
    Filed: January 23, 2020
    Publication date: July 29, 2021
    Inventors: Asaf PORAT-STOLER, Constantine GAVRILOV, Christopher M. DENNETT, Rivka MAYRAZ MATOSEVICH, Sergey MARENKOV, Jonathan FISCHER-TOUBOL, Afief HALUMI
  • Patent number: 10552243
    Abstract: Technology for handling page size mismatches when DPL-CLR is performed at multiple levels of a data storage system (for example, RAID level and flash card level). A “corrective DPL” corrects only a portion of the data that would make up a page at the level at which the data is stored (that is, the “initial DPL level”), and, after that, a partially corrected page of data is formed and stored in data storage, with the partially corrected page: (i) having a page size characteristic of the initial DPL; (ii) including the part of the data corrected by the corrective DPL; and (iii) further including other data. In some embodiments, the other data has a pattern that indicates that it is invalid, erroneous data, such that an error message will be returned if this portion of the data is attempted to be read.
    Type: Grant
    Filed: October 12, 2017
    Date of Patent: February 4, 2020
    Assignee: International Business Machines Corporation
    Inventors: Roman A. Pletka, Timothy J. Fisher, Robert E. Galbraith, Kevin E. Sallese, Christopher M. Dennett
  • Patent number: 10445016
    Abstract: A technique for handling storage commands includes receiving, by an interface node of a data storage system, a first storage command. The interface node determines whether the first storage command is a head of queue (HOQ) command. In response to determining the first storage command is an HOQ command, the interface node increments a constrained command count and issues the first storage command to a first worker processor core for processing. In response to determining the first storage command is not an HOQ command, the interface node processes the first storage command as a non-HOQ command.
    Type: Grant
    Filed: December 13, 2016
    Date of Patent: October 15, 2019
    Assignee: International Business Machines Corporation
    Inventors: Shawn P. Authement, Kevin A. Bosien, Christopher M. Dennett, David E. Mullen
  • Publication number: 20190114217
    Abstract: Technology for handling page size mismatches when DPL-CLR is performed at multiple levels of a data storage system (for example, RAID level and flash card level). A “corrective DPL” corrects only a portion of the data that would make up a page at the level at which the data is stored (that is, the “initial DPL level”), and, after that, a partially corrected page of data is formed and stored in data storage, with the partially corrected page: (i) having a page size characteristic of the initial DPL; (ii) including the part of the data corrected by the corrective DPL; and (iii) further including other data. In some embodiments, the other data has a pattern that indicates that it is invalid, erroneous data, such that an error message will be returned if this portion of the data is attempted to be read.
    Type: Application
    Filed: October 12, 2017
    Publication date: April 18, 2019
    Inventors: Roman A. Pletka, Timothy J. Fisher, Robert E. Galbraith, Kevin E. Sallese, Christopher M. Dennett
  • Publication number: 20180165038
    Abstract: A technique for handling storage commands includes receiving, by an interface node of a data storage system, a first storage command. The interface node determines whether the first storage command is a head of queue (HOQ) command. In response to determining the first storage command is an HOQ command, the interface node increments a constrained command count and issues the first storage command to a first worker processor core for processing. In response to determining the first storage command is not an HOQ command, the interface node processes the first storage command as a non-HOQ command.
    Type: Application
    Filed: December 13, 2016
    Publication date: June 14, 2018
    Inventors: SHAWN P. AUTHEMENT, KEVIN A. BOSIEN, CHRISTOPHER M. DENNETT, DAVID E. MULLEN
  • Patent number: 9798493
    Abstract: An interface receives a command corresponding to a non-volatile memory. The interface determines whether a bypass mode is enabled and whether the command is a medium-access command. A primary processing node processes the command in response to determining at least one of the following: that the bypass mode is disabled or that the command is not a medium-access command. A secondary processing node processes the command, in response to determining that the bypass mode is enabled and that the command is a medium-access command.
    Type: Grant
    Filed: December 16, 2013
    Date of Patent: October 24, 2017
    Assignee: International Business Machines Corporation
    Inventors: Shawn P. Authement, Christopher M. Dennett, Gowrisankar Radhakrishnan, Donald J. Ziebarth
  • Patent number: 9454433
    Abstract: Method and apparatus for redundant array of independent disks (RAID) recovery are disclosed. In one embodiment, a RAID controller schedules requests to rebuild failed drives based on the wear state of secondary drives and input/output (I/O) activity. The controller may be configured to assign higher scheduling priority to rebuild requests only when necessary, so as to reduce the time needed for the rebuild and to avoid affecting performance of the RAID system. In particular, the controller may give higher priority to rebuild requests if secondary drive failure is likely. In addition, the controller may determine when write-intensive periods occur, and assign lower priority to rebuild requests during such periods.
    Type: Grant
    Filed: June 11, 2014
    Date of Patent: September 27, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Christopher M. Dennett, Farnaz Toussi
  • Patent number: 9396068
    Abstract: Method and apparatus for redundant array of independent disks (RAID) recovery are disclosed. In one embodiment, a RAID controller schedules requests to rebuild failed drives based on the wear state of secondary drives and input/output (I/O) activity. The controller may be configured to assign higher scheduling priority to rebuild requests only when necessary, so as to reduce the time needed for the rebuild and to avoid affecting performance of the RAID system. In particular, the controller may give higher priority to rebuild requests if secondary drive failure is likely. In addition, the controller may determine when write-intensive periods occur, and assign lower priority to rebuild requests during such periods.
    Type: Grant
    Filed: April 17, 2014
    Date of Patent: July 19, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Christopher M. Dennett, Farnaz Toussi
  • Publication number: 20150301894
    Abstract: Method and apparatus for redundant array of independent disks (RAID) recovery are disclosed. In one embodiment, a RAID controller schedules requests to rebuild failed drives based on the wear state of secondary drives and input/output (I/O) activity. The controller may be configured to assign higher scheduling priority to rebuild requests only when necessary, so as to reduce the time needed for the rebuild and to avoid affecting performance of the RAID system. In particular, the controller may give higher priority to rebuild requests if secondary drive failure is likely. In addition, the controller may determine when write-intensive periods occur, and assign lower priority to rebuild requests during such periods.
    Type: Application
    Filed: April 17, 2014
    Publication date: October 22, 2015
    Applicant: International Business Machines Corporation
    Inventors: Christopher M. Dennett, Farnaz Toussi
  • Publication number: 20150301895
    Abstract: Method and apparatus for redundant array of independent disks (RAID) recovery are disclosed. In one embodiment, a RAID controller schedules requests to rebuild failed drives based on the wear state of secondary drives and input/output (I/O) activity. The controller may be configured to assign higher scheduling priority to rebuild requests only when necessary, so as to reduce the time needed for the rebuild and to avoid affecting performance of the RAID system. In particular, the controller may give higher priority to rebuild requests if secondary drive failure is likely. In addition, the controller may determine when write-intensive periods occur, and assign lower priority to rebuild requests during such periods.
    Type: Application
    Filed: June 11, 2014
    Publication date: October 22, 2015
    Inventors: Christopher M. DENNETT, Farnaz TOUSSI
  • Publication number: 20150169254
    Abstract: An interface receives a command corresponding to a non-volatile memory. The interface determines whether a bypass mode is enabled and whether the command is a medium-access command. A primary processing node processes the command in response to determining at least one of the following: that the bypass mode is disabled or that the command is not a medium-access command. A secondary processing node processes the command, in response to determining that the bypass mode is enabled and that the command is a medium-access command.
    Type: Application
    Filed: December 16, 2013
    Publication date: June 18, 2015
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Shawn P. Authement, Christopher M. Dennett, Gowrisankar Radhakrishnan, Donald J. Ziebarth