Patents by Inventor Masahiro Tsumagari

Masahiro Tsumagari 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).

  • Disk array apparatus, data migration method, and storage medium
    Patent number: 7594076
    Abstract: The disk array apparatus has a source volume that is the source for data migration, and migrates the data to a destination volume that is the destination for the data migration. The disk array apparatus includes: an access frequency calculator for calculating the frequency of access to the source volume for each time period of a certain length of time going back from a data migration termination date and time when the data migration termination date and time is designated externally; an estimated data migration amount calculator for calculating the estimated data migration amount for each time period based on the access frequency calculated by the access frequency calculator; and a data migration start date and time calculator for calculating the data migration start date and time based on the estimated data migration amount calculated by the estimated data migration amount calculator.
    Type: Grant
    Filed: January 10, 2006
    Date of Patent: September 22, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Masahiro Tsumagari, Haruaki Watanabe, Takao Satoh
  • Disk array apparatus, data migration method, and storage medium
    Publication number: 20070061513
    Abstract: The present invention proposes a disk array apparatus that can dramatically enhance its operability. The disk array apparatus has a source volume that is the source for data migration, and migrates the data to a destination volume that is the destination for the data migration. The disk array apparatus includes: an access frequency calculator for calculating the frequency of access to the source volume for each time period of a certain length of time going back from a data migration termination date and time when the data migration termination date and time is designated externally; an estimated data migration amount calculator for calculating the estimated data migration amount for each time period based on the access frequency calculated by the access frequency calculator; and a data migration start date and time calculator for calculating the data migration start date and time based on the estimated data migration amount calculated by the estimated data migration amount calculator.
    Type: Application
    Filed: January 10, 2006
    Publication date: March 15, 2007
    Inventors: Masahiro Tsumagari, Haruaki Watanabe, Takao Satoh