Abstract: A storage system comprises a first controller and a plurality of storage devices. The plurality of storage devices configure RAID, each of which includes one or more non-volatile memory chips providing storage space where data from a host computer is stored, and a second controller coupled to the non-volatile memory chips. In case where the first controller receives an update request to update first data to second data from the host computer, the second controller in a first storage device of the storage devices is configured to store the second data in an area different from an area where the first data has been stored, in the storage space of the first storage device; generate information that relates the first data and the second data; and generate an intermediate parity based on the first and the second data.

Abstract: A storage system stores multiple copies of data on physical storage implemented, for example, with multiple disk units. Input/output read requests are received from host systems and distributed in a manner that allows parallel read operations to be conducted over the multiple disk units of the physical storage.

Abstract: In response to requests for I/O processing sent from a computer, I/O which should be processed at a priority is enabled to be processed without being affected by other processing, by classifying I/O into those to be processed at a priority and those not to be processed at a priority. The storage control apparatus comprises an I/O processing controller with a memory that is common for the whole controller. The storage control apparatus manages information for dividing and controlling a plurality of I/O processes as priority and non-priority in that memory and operates while suppressing non-priority I/O processing on the basis of information in the memory.

Abstract: A storage system stores multiple copies of data on physical storage implemented, for example, with multiple disk units. Input/output read requests are received from host systems and distributed in a manner that allows parallel read operations to be conducted over the multiple disk units of the physical storage.

Abstract: A method of respectively reading and writing data to and from a plurality of physical disk units in response to I/O requests from a host computing system includes establishing a logical disk group having a number of logical disk elements, mapping each of the logical disk elements to corresponding physical disk units, receiving from the host computing system an I/O request for data to select a one of the number of logical disk elements, accessing the physical disk unit corresponding to the selected one logical disk to access for the data, and transferring the accessed data to the host computing system.

Abstract: In response to requests for I/O processing sent from a computer, I/O which should be processed at a priority is enabled to be processed without being affected by other processing, by classifying I/O into those to be processed at a priority and those not to be processed at a priority. The storage control apparatus comprises an I/O processing controller with a memory that is common for the whole controller. The storage control apparatus manages information for dividing and controlling a plurality of I/O processes as priority and non-priority in that memory and operates while suppressing non-priority I/O processing on the basis of information in the memory.

Abstract: In a disk array of the RAID constitution, a likelihood of occurrence of a failure is predicted from the number of times of error occurrence for each of disk drives #0 to #3 in a certain parity group. Two storage areas #0_UH and #2_LH of a half size, which are different in data stripes from each other, are selected from two disk drives #0 and #2 having a relatively high likelihood of occurrence of a failure, respectively, and the data thereof is copied to a spare disk #A (divided data copy). When the likelihood of occurrence of a failure of one disk drive #0 further increases, the remaining half storage area #OLH of the disk drive #0 is copied to the spare disk #A (dynamic sparing). Dynamic sparing time is reduced and a likelihood of data lost due to a multiple disk failure by employing the divided data copy processing.

Abstract: In response to requests for I/O processing sent from a computer, I/O which should be processed at a priority is enabled to be processed without being affected by other processing, by classifying I/O into those to be processed at a priority and those not to be processed at a priority. The storage control apparatus comprises an I/O processing controller with a memory that is common for the whole controller. The storage control apparatus manages information for dividing and controlling a plurality of I/O processes as priority and non-priority in that memory and operates while suppressing non-priority I/O processing on the basis of information in the memory.

Abstract: The control unit arbitrarily with respect to the CPU, including according to an algorithm that is independent of the request a disk unit among the disk units that are inactive when the control unit receives an input/output request involving either read or staging. For a write request from the CPU, the control unit selects a specific disk unit in the disk unit group for the immediate writing of data. In the second kind of load distribution a disk unit is selected to execute read and staging other than the above-mentioned specific disk.

Abstract: In order to construct an integrated storage system by reinforcing collaboration of components or functions of a storage system in which a storage area network (SAN) is used, in a computer system having multiple client computers, multiple various servers, multiple various storages which keep data, and a local area network (LAN) which connects the computers and the servers, a storage area network (SAN) which lies between the servers and storages forms a switched circuit network which is capable of connecting any server and any storage through fiber channel FC switches. The computer system further includes a terminal which is equipped with operation and management software which performs storage management including management of logical volumes in the various storages, data arrangement, error monitoring, management of setting up the FC switches, and backup for data in the storages.

Abstract: A disk storage system has a control unit having a plurality of external ports connectable to a mirrored disk including two disks to which write data is written. When the control unit receives two read requests issued from a processor to the disk unit group, a first read operation is performed to read data requested by the first read request from one of the disks and a second read operation is performed to read data requested by the second read request from the other one of the disks. Also, a first transferring operation is performed to transfer data read by the first read operation to one external port of the control unit and a second transferring operation is performed to transfer data read by the second read operation to another external port of the control unit. Further, the data read by the two read operations is transferred to the processor via the external ports.

Abstract: In response to requests for I/O processing sent from a computer, I/O which should be processed at a priority is enabled to be processed without being affected by other processing, by classifying I/O into those to be processed at a priority and those not to be processed at a priority. The storage control apparatus comprises an I/O processing controller with a memory that is common for the whole controller. The storage control apparatus manages information for dividing and controlling a plurality of I/O processes as priority and non-priority in that memory and operates while suppressing non-priority I/O processing on the basis of information in the memory.

Abstract: In a disk array of the RAID constitution, a likelihood of occurrence of a failure is predicted from the number of times of error occurrence for each of disk drives #0 to #3 in a certain parity group. Two storage areas #0_UH and #2_LH of a half size, which are different in data stripes from each other, are selected from two disk drives #0 and #2 having a relatively high likelihood of occurrence of a failure, respectively, and the data thereof is copied to a spare disk #A (divided data copy). When the likelihood of occurrence of a failure of one disk drive #0 further increases, the remaining half storage area #OLH of the disk drive #0 is copied to the spare disk #A (dynamic sparing). Dynamic sparing time is reduced and a likelihood of data lost due to a multiple disk failure by employing the divided data copy processing.

Abstract: In response to requests for I/O processing sent from a computer, I/O which should be processed at a priority is enabled to be processed without being affected by other processing, by classifying I/O into those to be processed at a priority and those not to be processed at a priority. The storage control apparatus comprises an I/O processing controller with a memory that is common for the whole controller. The storage control apparatus manages information for dividing and controlling a plurality of I/O processes as priority and non-priority in that memory and operates while suppressing non-priority I/O processing on the basis of information in the memory.

Abstract: A storage system stores multiple copies of data on physical storage implemented, for example, with multiple disk units. Input/output read requests are received from host systems and distributed in a manner that allows parallel read operations to be conducted over the multiple disk units of the physical storage.

Abstract: A method of respectively reading and writing data to and from a plurality of physical disk units in response to I/O requests from a host computing system includes establishing a logical disk group having a number of logical disk elements, mapping each of the logical disk elements to corresponding physical disk units, receiving from the host computing system an I/O request for data to select a one of the number of logical disk elements, accessing the physical disk unit corresponding to the selected one logical disk to access for the data, and transferring the accessed data to the host computing system.

Abstract: In order to construct an integrated storage system by reinforcing collaboration of components or functions of a storage system in which a storage area network (SAN) is used, in a computer system comprising multiple client computers, multiple various servers, multiple various storages which keep data, a local area network (LAN) which connects the computers and the servers, a storage area networks (SAN) which lies between the servers and said storages, the SAN forms a switched circuit network which is capable of connecting any servers and any storages through fiber channel switches, and the computer system further comprises a terminal which is equipped with operation and management software which performs storage management including management of logical volumes in the various storages, data arrangement, and error monitoring, management of setting up said FC switches, and backup operation for data in said storages.

Abstract: In order to construct an integrated storage system by reinforcing collaboration of components or functions of a storage system in which a storage area network (SAN) is used, in a computer system comprising multiple client computers, multiple various servers, multiple various storages which keep data, a local area network (LAN) which connects the computers and the servers, a storage area networks (SAN) which lies between the servers and said storages, the SAN forms a switched circuit network which is capable of connecting any servers and any storages through fiber channel switches, and the computer system further comprises a terminal which is equipped with operation and management software which performs storage management including management of logical volumes in the various storages, data arrangement, and error monitoring, management of setting up said FC switches, and backup operation for data in said storages.

Abstract: In order to construct an integrated storage system by reinforcing collaboration of components or functions of a storage system in which a storage area network (SAN) is used, in a computer system comprising multiple client computers, multiple various servers, multiple various storages which keep data, a local area network (LAN) which connects the computers and the servers, a storage area networks (SAN) which lies between the servers and said storages, the SAN forms a switched circuit network which is capable of connecting any servers and any storages through fiber channel switches, and the computer system further comprises a terminal which is equipped with operation and management software which performs storage management including management of logical volumes in the various storages, data arrangement, and error monitoring, management of setting up said FC switches, and backup operation for data in said storages.

Abstract: The control unit arbitrarily with respect to the CPU, including according to an algorithm that is independent of the request a disk unit among the disk units that are inactive when the control unit receives an input/output request involving either read or staging. For a write request from the CPU, the control unit selects a specific disk unit in the disk unit group for the immediate writing of data. In the second kind of load distribution a disk unit is selected to execute read and staging other than the above-mentioned specific disk.