Patent ID: 8225036

Claim:
A storage controller connected to a host computer, the storage controller comprising: a plurality of nonvolatile memory modules having a plurality of nonvolatile memory chips for storing data from the host computer; a nonvolatile memory control unit for controlling data input to and output from the host computer by controlling a power source for the nonvolatile memory modules; a cache memory configured to temporarily store data input or data output from the host computer; wherein when reading or writing data from or to a designated nonvolatile memory module at a specified time in response to a data read/write request from the host computer, the nonvolatile memory control unit performs power-on control to turn on the power source for only the designated nonvolatile memory module; a plurality of logical volumes formed in storage areas of a plurality of hard disk drives, that store data from the host computer; and a plurality of nonvolatile memory packages composed of the plurality of nonvolatile memory modules; wherein each of the nonvolatile memory packages includes the plurality of nonvolatile memory modules and the nonvolatile memory control unit; wherein the same number of Error Correcting Code (ECC) groups are formed in a hard disk drive group composed of the plurality of hard disk drives as the number of ECC groups are formed in a nonvolatile memory package group composed of the plurality of nonvolatile memory packages; wherein the data from the host computer is stored in a designated logical volume; and wherein when the data stored in the designated logical volume is migrated to the nonvolatile memory module belonging to the ECC group that corresponds to the ECC group to which the designated logical volume belongs, power-on control is performed on an ECC group basis to turn on only the power source for the designated nonvolatile memory module.