| 摘要 |
A storage system is provided with: a plurality of semiconductor storage devices having a plurality of nonvolatile semiconductor memory chips, cache memory, and a processor; and a storage controller for controlling the plurality of semiconductor storage devices as a RAID group and storing user data and parity data in the plurality of semiconductor storage devices. The storage controller correlates one from among a plurality of sub-logical storage areas in each of the plurality of semiconductor storage devices to each of a plurality of extents one by one, and transmits configuration information indicating correspondence between the arrangement of user data and parity data in a logical address space and the plurality of extents and then a lookahead command indicating that the data be stored in the cache memory to each of the plurality of semiconductor storage devices. In accordance with the lookahead command received, the processor of the semiconductor storage devices reads the user data and parity data corresponding to the extent from the plurality of nonvolatile semiconductor memory chips on the basis of the configuration information and stores the read data in the cache memory. |
