STORAGE SYSTEM AND METHOD OF CONTROL FOR STORAGE SYSTEM

摘要

The storage system includes a plurality of storage devices and a storage controller. The storage controller stores a data request quantity indicating the data quantity of write data written to the target area in a specific period, and estimates, based on the quantity of request data and relationship information received from storage devices, the estimated data quantity written to the nonvolatile semiconductor memory chips based on the write data written to the target area in the specific period. The storage controller selects a second logical storage area with an estimated data quantity less than an estimated data quantity for the first logical storage area and assigned to a storage device different from a storage device assigned to the first logical storage area, and migrates the first data stored in the first logical storage area to the second logical storage area.

主权项

1. A storage system comprising:
a plurality of storage devices; and a storage controller coupled to the plurality of storage devices and a host computer, wherein each of the plurality of storage devices includes a plurality of nonvolatile semiconductor memory chips, and a memory controller coupled to the plurality of nonvolatile semiconductor memory chips and the storage controller, the storage controller assigns storage areas provided by each of the plurality of storage devices to a plurality of logical storage areas, when the storage controller receives a write instruction and write data from the host computer, selects a logical storage area from among the plurality of logical storage areas, selects a storage device assigned to the selected logical storage area from among the plurality of storage devices, and transmits the write data to the selected storage device, when the memory controller receives the write data from the storage controller, converts the write data to compressed data by compressing the write data, writes the compressed data to any of the plurality of nonvolatile semiconductor memory chips, and transmits to the storage controller relationship information containing relationship between a data quantity of the write data and a data quantity of the compressed data, the storage controller regards each of the plurality of logical storage areas as a target area, stores a request data quantity indicating the data quantity of write data written to the target area in a specific period, and regards, based on the request data quantity and the relationship information, as an estimated data quantity of the target area a quantity of data written to the plurality of nonvolatile semiconductor memory chips based on write data written to the target area in the specific period, and the storage controller selects a first logical storage area from among the plurality of logical storage areas, selects from among the plurality of logical storage areas a second logical storage area with an estimated data quantity less than an estimated data quantity of the first logical storage area and assigned to a storage device different from a storage device assigned to the first logical storage area, and migrates first data stored in the first logical storage area to the second logical storage area.