| 主权项 |
1. A tiered storage system comprising:
a tiered storage device; and a computer which uses the tiered storage device, wherein: the tiered storage device comprises
a plurality of storage devices having different, access performance; anda storage controller which controls accesses to the storage devices, the storage controller managing counts of accesses to logical blocks in a logical unit, to which storage areas of the storage devices are allocated block by block, in association with logical block addresses indicating the logical blocks, the storage controller relocating, to one of the storage devices, data stored in the logical blocks, based on access counts associated with the respective logical block addresses; the computer comprises
a file system which issues a read request or a write request including a logical block address associated with a to-be-accessed block, in accordance with an access request issued from an application operating on the computer and including a filename and relative position information, the relative position information indicating a relative position of the to-be-accessed block included in a file indicated by the filename; anda device driver which accesses the tiered storage device by sending, to the storage controller, the read request or the write request from the file system; one of the computer and the tiered storage device further comprises a correction support unit which supports correction of the access counts managed by the storage controller; the file system manages a file, requested by the application, by associating relative positions, in the file, of blocks constituting The file, with logical block addresses of logical blocks storing data of the blocks constituting the file, and performs, using the device driver, a copy-on-write operation when the access request is a write request WR which requests overwriting of data, the copy-on-write operation including copying to-be-overwritten data from a first logical block storing the to-be-overwritten data to a second logical block different from the first logical block, and then writing, to the second logical block, data designated by the write request WR; and the correction support unit causes the storage controller to carry over an access count managed by the storage controller and associated with a logical block address indicating the first logical block as a copy source in the copy-on-write operation, to an access count associated with a logical block address indicating the second logical block as a copy destination in the copy-on-write operation. |
