Abstract: A storage system includes a storage drive that stores data and a plurality of storage apparatuses, each generating access data and writing data into the storage drive, and accessing data in the storage drive using the access data, and in a case of migrating the volume together with the access data between the storage apparatuses, one responsible for the write processing on the volume being migrated to a migration destination storage apparatus at a time of migration of the access data, and one responsible for the read processing on the volume being performed by a migration source storage apparatus using the access data, and the one responsible for the read processing being migrated to the migration destination storage apparatus after the access data is available for the migration destination storage apparatus.

Abstract: In a case of exchanging a migration source storage controller and a migration destination storage controller sharing one storage medium during replacement of storage devices, when hardware configurations or data management forms of the storage controllers are different, data in the storage medium cannot be shared even when data management information can be copied. Accordingly, a storage system, having a storage control unit and a storage drive provided with a storage medium, includes data management information for accessing data in the storage drive. A first storage control unit copies data management information about the data in the storage drive to a second storage control unit. When a write request is received from a host after copying of the data management information begins, each of the first storage and second storage control units stores write data related to the write request in a separate storage area of the storage drive.

Abstract: To combine and apply a data volume reduction technique and an automatic tier management function, the invention provides a storage system that includes a processor and a storage medium and manages and stores data in tiers. The storage system includes a first storage tier that includes a storage area for storing data, and a second storage tier that includes a storage area for storing the data which is stored in the storage area of the first storage tier and whose storage area is changed. The processor calculates an I/O volume of the data in the first storage tier, determines the tier where data is stored based on the I/O volume, and physically stores data which is stored in the second storage tier in a storage medium corresponding to the determined tier.

Abstract: In a case of exchanging a migration source storage controller and a migration destination storage controller sharing one storage medium during replacement of storage devices, when hardware configurations or data management forms of the storage controllers are different, data in the storage medium cannot be shared even when data management information can be copied. Accordingly, a storage system, having a storage control unit and a storage drive provided with a storage medium, includes data management information for accessing data in the storage drive. A first storage control unit copies data management information about the data in the storage drive to a second storage control unit. When a write request is received from a host after copying of the data management information begins, each of the first storage and second storage control units stores write data related to the write request in a separate storage area of the storage drive.

Abstract: With omission of a duplication process of compressed data, a cache access frequency is reduced to improve throughput. A storage system includes first and second control units and a storage drive. Upon receiving a data write command, the first control unit stores data to be subjected to the write command in a first cache area of the first control unit, and stores the data in a second cache area of the second control unit to perform duplication, and upon completion of the duplication, the first control unit transmits a response indicating an end of write, performs a predetermined process on the data to be subjected to the write command, stores the data in a buffer area, reads the data stored in the buffer area, and transmits the read data to the storage drive.

Abstract: Each of a storage apparatus having a primary volume and a storage apparatus having a secondary volume, upon reception of a write command, changes a data attribute of a data area allocated to an address designated by the write command, to a first attribute if the data attribute is other than the first attribute. In an offloaded data copy processing sequence, each of the storage apparatus changes a data attribute of a data area allocated to a copy source address to a second attribute if the data attribute is other than the second attribute. When an allocation information copy process is to be performed to allocate the data area to a copy destination address according to an offloaded data copy command, each of the storage apparatus discontinues the offloaded data copy processing sequence if the data attribute of the data area is the first attribute.

Abstract: With omission of a duplication process of compressed data, a cache access frequency is reduced to improve throughput. A storage system includes first and second control units and a storage drive. Upon receiving a data write command, the first control unit stores data to be subjected to the write command in a first cache area of the first control unit, and stores the data in a second cache area of the second control unit to perform duplication, and upon completion of the duplication, the first control unit transmits a response indicating an end of write, performs a predetermined process on the data to be subjected to the write command, stores the data in a buffer area, reads the data stored in the buffer area, and transmits the read data to the storage drive.

Abstract: To combine and apply a data volume reduction technique and an automatic tier management function, the invention provides a storage system that includes a processor and a storage medium and manages and stores data in tiers. The storage system includes a first storage tier that includes a storage area for storing data, and a second storage tier that includes a storage area for storing the data which is stored in the storage area of the first storage tier and whose storage area is changed. The processor calculates an I/O volume of the data in the first storage tier, determines the tier where data is stored based on the I/O volume, and physically stores data which is stored in the second storage tier in a storage medium corresponding to the determined tier.

Abstract: A storage system according to an aspect of the present invention includes one or more storage devices for storing write data to which a write request from a host computer is directed, and a storage controller that provides one or more volumes to the host computer. Further, the storage system manages the time when a write request is last received from the host computer for each partition within the volume. Then, the storage controller performs a deduplication process upon detecting the partition not receiving a write request for a predetermined time or more from the time when the write request is last received.

Abstract: With omission of a duplication process of compressed data, a cache access frequency is reduced to improve throughput. A storage system includes first and second control units and a storage drive. Upon receiving a data write command, the first control unit stores data to be subjected to the write command in a first cache area of the first control unit, and stores the data in a second cache area of the second control unit to perform duplication, and upon completion of the duplication, the first control unit transmits a response indicating an end of write, performs a predetermined process on the data to be subjected to the write command, stores the data in a buffer area, reads the data stored in the buffer area, and transmits the read data to the storage drive.

Abstract: Each of a storage apparatus having a primary volume and a storage apparatus having a secondary volume, upon reception of a write command, changes a data attribute of a data area allocated to an address designated by the write command, to a first attribute if the data attribute is other than the first attribute. In an offloaded data copy processing sequence, each of the storage apparatus changes a data attribute of a data area allocated to a copy source address to a second attribute if the data attribute is other than the second attribute. When an allocation information copy process is to be performed to allocate the data area to a copy destination address according to an offloaded data copy command, each of the storage apparatus discontinues the offloaded data copy processing sequence if the data attribute of the data area is the first attribute.

Abstract: A storage system according to an aspect of the present invention includes one or more storage devices for storing write data to which a write request from a host computer is directed, and a storage controller that provides one or more volumes to the host computer. Further, the storage system manages the time when a write request is last received from the host computer for each partition within the volume. Then, the storage controller performs a deduplication process upon detecting the partition not receiving a write request for a predetermined time or more from the time when the write request is last received.