Patents by Inventor Krishnakumar R. Surugucchi

Krishnakumar R. Surugucchi 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: 8601348
    Abstract: Provided are a method, system, and article of manufacture for error checking addressable blocks in storage. Addressable blocks of data are stored in a storage in stripes, wherein each stripe includes a plurality of data blocks for one of the addressable blocks and at least one checksum block including checksum data for the addressable block. A write request is received to modify data in one of the addressable blocks. The write and updating the checksum are performed in the stripe having the modified addressable block. An indication is made to perform an error checking operation on the stripe for the modified addressable block in response to the write request, wherein the error checking operation reads the data blocks and the checksum in the stripe to determine if the checksum data is accurate. An error handling operation is initiated in response to determining that the checksum data is not accurate.
    Type: Grant
    Filed: January 15, 2013
    Date of Patent: December 3, 2013
    Assignee: International Business Machines Corporation
    Inventors: James L. Hafner, David R. Kahler, Robert A. Kubo, David F. Mannenbach, Karl A. Nielsen, James A. O'Connor, Richard B. Stelmach, Krishnakumar R. Surugucchi
  • Publication number: 20100251072
    Abstract: A RAID system is provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.
    Type: Application
    Filed: June 10, 2010
    Publication date: September 30, 2010
    Applicant: IBM Corporation
    Inventors: James L. Hafner, Carl E. Jones, David R. Kahler, Robert A. Kubo, David F. Mannenbach, Karl A. Nielsen, James A. O'Connor, Krishnakumar R Surugucchi
  • Patent number: 7793167
    Abstract: Methods are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.
    Type: Grant
    Filed: August 23, 2007
    Date of Patent: September 7, 2010
    Assignee: International Business Machines Corporation
    Inventors: James L. Hafner, Carl E. Jones, David R. Kahler, Robert A. Kubo, David F. Mannenbach, Karl A. Nielsen, James A. O'Conner, Krishnakumar R. Surugucchi
  • Publication number: 20090055584
    Abstract: Method, system and computer program product are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.
    Type: Application
    Filed: August 23, 2007
    Publication date: February 26, 2009
    Applicant: IBM CORPORATION
    Inventors: James L. Hafner, Carl E. Jones, David R. Kahler, Robert A. Kubo, David F. Mannenbach, Karl A. Nielsen, James A. O'Conner, Krishnakumar R. Surugucchi
  • Publication number: 20090055688
    Abstract: Methods are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is, changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.
    Type: Application
    Filed: August 23, 2007
    Publication date: February 26, 2009
    Applicant: IBM CORPORATION
    Inventors: James L. Hafner, Carl E. Jones, David R. Kahler, Robert A. Kubo, David F. Mannenbach, Karl A. Nielsen, James A. O'Connor, Krishnakumar R. Surugucchi