Abstract: The invention is a copy processing technique in a data processing system, which can simultaneously achieve long-distance communication and no data loss when disaster occurs. Among a production site, a local site, and a remote site, long-distance remote copying from a disk array device at the production site to a disk array device at the remote site without data loss is achieved via a disk array device at the local site in combination with synchronous remote copying and asynchronous remote copying. Also, in the disk array devices at the local site and the remote site, copying is performed through a replica function. Even if the production site is affected by disaster, tasks can be continued at the local site having the same data as that of the production site and at the remote site a long distance away from the production site.

Abstract: The present invention provides a storage system and a method of controlling the storage system, in which a second site rapidly resumes system process when a first site is damaged. The storage system comprises a first site including a first storage device, a second site including a second storage device, and a third site including a third storage device, and the method of controlling the storage system comprises a step of making a logical volume of the second storage device consistent with a logical volume of the first storage device by remotely copying only the differential data between the logical volume of the first storage device and the logical volume of the second storage device from a logical volume of the third storage device to the logical volume of the second storage device when the first site is damaged.

Abstract: A method for managing data stored in a hierarchical storage unit of a storage apparatus is disclosed. The storage unit includes a first storage medium having a first access speed and a second storage medium having a second access speed. The first access speed is different from the second access speed. The method comprises determining a first access frequency for information of first type, the first access frequency being associated with a first period of past time. A second access frequency of the information of first type is determined. The second access frequency is associated with a second period of past time and is different than the first access frequency. At least a portion of the information of first type is transferred from the first storage medium to the second storage medium prior to a second period based on the second access frequency determined in the determining-a-second-access-frequency step, the second period corresponding to the second period of past time.

Abstract: When plural copy groups including pairs exist, remote copying for pairs belonging to copy groups is suspended selectively on a copy group-to-copy group basis, instead of suspending remote copying in all the copy groups at once. A computer system has a host computer, plural first storage systems comprising plural first logical disks, and plural second storage systems comprising plural second logical disks. A first logical disk and a second logical disk paired with the first logical disk, and each pair belongs to either a first copy group or a second copy group. To selectively suspend remote copying on a copy group-to-copy group basis, one of the copy groups is specified first and then pairs belonging to this copy group are designated. The first storage systems comprising first logical disks of the designated pairs suspend remote copy processing for the designated pairs.

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: A storage controller calculates an access frequency of each logical disk; that is selects a first logical disk device of which the access frequency exceeds a first predetermined value, the first logical disk device being allocated to a first physical disk device; selects a second logical disk device which has the access frequency equal to or less than a second predetermined value, the second logical disk device being allocated to a second physical disk device; and reallocates the first and second logical device; and reallocates the first and second logical devices to the second and the first physical disk device, respectively.

Abstract: The present invention creates real data and parity data using plural hard disk control units without changing the number of disk adapters per hard disk control unit and distributes and stores data in a hard disk. While it is being requested that a disk utilization rate is increased maintaining the failure resistance of the hard disk, and, at the same time, to support the combination of the real data+parity data as before, it is desirable that the number of adapters that comprise the hard disk control unit should not be changed. According to the present invention, the number of hard disks that comprise RAID can be changed without changing the number of disk adapters per hard disk control unit.

Abstract: A method for managing data stored in a hierarchical storage unit of a storage apparatus is disclosed. The storage unit includes a first storage medium having a first access speed and a second storage medium having a second access speed. The first access speed is different from the second access speed. The method comprises determining a first access frequency for information of first type, the first access frequency being associated with a first period of past time. A second access frequency of the information of first type is determined. The second access frequency is associated with a second period of past time and is different than the first access frequency. At least a portion of the information of first type is transferred from the first storage medium to the second storage medium prior to a second period based on the second access frequency determined in the determining-a-second-access-frequency step, the second period corresponding to the second period of past time.

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 a system having a handsfree function to answer an incoming call handsfree and another function, when an incoming call arrives, a handsfree unit informs a user about an arrival of the incoming call and sets a user operation invalid state in which any user operation is made invalid during a predetermined period. The handsfree unit regards a user operation performed after the predetermined period passes as an operation for the incoming call, and performs incoming call answering processing corresponding to the user operation. When a user operation is performed in the user operation invalid state, the handsfree unit causes the user operation to be invalid.

Abstract: A storage controller calculates an access frequency of each logical disk; that it selects a first logical disk device of which the access frequency exceeds a first predetermined value, the first logical disk device being allocated to a first physical disk device; selects a second logical disk device which has the access frequency equal to or less than a second predetermined value, the second d logical disk device being allocated to a second physical disk device; and reallocates the first and second logical device; and reallocates the first and second logical devices to the second and the first physical disk device, respectively.

Abstract: A method for verifying data in a storage system is disclosed. A host computer transmits area management data to a storage controller. The area management data specifies a range of a storage area in a storage device to be used by an application program having a mechanism for verifying data suitability. Upon receipt of an input/output request transmitted from the host computer, the storage controller performs verification, which is usually performed by the application program, of the data that is to be processed according to the data input/output request and to be input/output to/from the storage area, which is specified in accordance with the received area management data.

Abstract: The present invention provides a storage system and a method of controlling the storage system, in which a second site rapidly resumes system process when a first site is damaged. The storage system comprises a first site including a first storage device, a second site including a second storage device, and a third site including a third storage device, and the method of controlling the storage system comprises a step of making a logical volume of the second storage device consistent with a logical volume of the first storage device by remotely copying only the differential data between the logical volume of the first storage device and the logical volume of the second storage device from a logical volume of the third storage device to the logical volume of the second storage device when the first site is damaged.

Abstract: A method for verifying data in a storage system is disclosed. A host computer transmits area management data to a storage controller. The area management data specifies a range of a storage area in a storage device to be used by an application program having a mechanism for verifying data suitability. Upon receipt of an input/output request transmitted from the host computer, the storage controller performs verification, which is usually performed by the application program, of the data that is to be processed according to the data input/output request and to be input/output to/from the storage area, which is specified in accordance with the received area management 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: When a bus is used as a data communication channel, data within a disk unit cannot be reproduced or copied into a spare disk while a control unit is making read/write processing based on a request from a host computer, or vice versa. Thus, a loop is constructed by a fiber channel capable of time division multiplex function, and the processing between the disk unit and the spare is performed not through the control unit so that the data within the disk can be copied into the spare while the processing between the host computer and the disk unit is being performed, or both processing operations can be executed in parallel.

Abstract: When a bus is used as a data communication channel, data within a disk unit cannot be reproduced or copied into a spare disk while a control unit is making read/write processing based on a request from a host computer, or vice versa. Thus, a loop is constructed by a fiber channel capable of time division multiplex function, and the processing between the disk unit and the spare is performed not through the control unit so that the data within the disk can be copied into the spare while the processing between the host computer and the disk unit is being performed, or both processing operations can be executed in parallel.

Abstract: When a bus is used as a data communication channel, data within a disk unit cannot be reproduced or copied into a spare disk while a control unit is making read/write processing based on a request from a host computer, or vice versa. Thus, a loop is constructed by a fiber channel capable of time division multiplex function, and the processing between the disk unit and the spare is performed not through the control unit so that the data within the disk can be copied into the spare while the processing between the host computer and the disk unit is being performed, or both processing operations can be executed in parallel.

Abstract: When a bus is used as a data communication channel, data within a disk unit cannot be reproduced or copied into a spare disk while a control unit is making read/write processing based on a request from a host computer, or vice versa. Thus, a loop is constructed by a fiber channel capable of time division multiplex function, and the processing between the disk unit and the spare is performed not through the control unit so that the data within the disk can be copied into the spare while the processing between the host computer and the disk unit is being performed, or both processing operations can be executed in parallel.

Abstract: A storage controller calculates an access frequency of each logical disk; that it selects a first logical disk device of which the access frequency exceeds a first predetermined value, the first logical disk device being allocated to a first physical disk device; selects a second logical disk device which has the access frequency equal to or less than a second predetermined value, the second d logical disk device being allocated to a second physical disk device; and reallocates the first and second logical device; and reallocates the first and second logical devices to the second and the first physical disk device, respectively.