STORAGE SYSTEM PROVIDING VIRTUAL VOLUMES

摘要

Multiple storage area groups into which multiple storage areas provided by multiple storage devices are classified with reference to storage area attributes are managed. The multiple logical volumes to which, in accordance with a write request to at least one address included in multiple addresses in the logical volume, at least one storage area included in the multiple storage areas is allocated are provided. In accordance with the access condition of the at least one address in the logical volume, the data written to the at least one address by the write request is migrated from the at least one storage area included in one of the multiple storage area groups to at least one storage area in another storage area group included in the multiple storage area groups.

主权项

1. A storage system comprising:
a plurality of storage devices including several types of storage devices; a controller providing a plurality of RAID groups which are composed of one type of the storage devices,
a plurality of tiers which are composed of the RAID groups,a pool which are composed of the plurality of tiers, anda virtual volume which is provided from the pool; and a memory storing a tier management information including a tier number, a top of tier I/O frequency range and a bottom of tier I/O frequency range, wherein, if an I/O frequency of data of a lower performance tier is greater than a tier I/O frequency border value which is higher than the bottom of the tier I/O frequency range of a higher performance tier, the controller reallocates the data from the lower performance tier to the higher performance tier, and wherein, if an I/O frequency of data of a lower performance tier is greater than the bottom of the tier I/O frequency range of the higher performance tier but lower than the tier I/O frequency border value, the controller does not reallocate the data from the lower performance tier to the higher performance tier.