摘要:
A computer system which has a plurality of computers and a storage device subsystem connected to the plurality of computers. The storage device subsystem has a plurality of storage devices and a plurality of interfaces, through which the subsystem is connected to the computers. One of the plurality of computers has a management means for holding therein data indicative of the storage devices and a connection relationship between the computers and storage device subsystem. Each computer, when wanting a new device, informs the management means of its capacity and type. The management means receives its notification and selects one of the storage devices which satisfies the request. And the management means instructs the storage device subsystem to set predetermined data in such a manner that the computer can access the selected device. The management means also returns predetermined data to the computer as a device assignment requester, the assignment requester computer modifies setting thereof to allow the computer in question can use the assigned device.
摘要:
A computer system which has a plurality of computers and a storage device subsystem connected to the plurality of computers. The storage device subsystem has a plurality of storage devices and a plurality of interfaces, through which the subsystem is connected to the computers. One of the plurality of computers has a management means for holding therein data indicative of the storage devices and a connection relationship between the computers and storage device subsystem. Each computer, when wanting a new device, informs the management means of its capacity and type. The management means receives its notification and selects one of the storage devices which satisfies the request. And the management means instructs the storage device subsystem to set predetermined data in such a manner that the computer can access the selected device. The management means also returns predetermined data to the computer as a device assignment requester, the assignment requester computer modifies setting thereof to allow the computer in question can use the assigned device.
摘要:
A storage has NAS and SAN functions and a high degree of freedom to configure a system to reduce the management and operation cost. The storage includes a plurality of interface slots in which a plurality of interface controllers can be installed, a block I/O interface controller which has SAN functions and which can be installed in the slot, a file I/O interface controller which has NAS functions and which can be installed in the slots, a storage capacity pool including a plurality of disk devices accessible from the interface controllers, and a storage capacity pool controller to control the storage capacity pool.
摘要:
An intermediate value derived from old and new data record values or old and new data themselves are sent from a control unit to a disk unit which stores a parity record as information necessary for updating parity. The disk unit reads an old parity record and generates a new value of parity record based on the read old parity and the information received from the control unit. The generated new value is stored in an empty record on the storage medium to which a read/write head is first positioned after the generation of the new value and in which effective data has not been stored. In a disk array system, a time required to update the parity record due to the updating of the data record is reduced and a performance of the storage unit subsystem is improved.
摘要:
An intermediate value derived from old and new data record values or old and new data themselves are sent from a control unit to a disk unit which stores a parity record as information necessary for updating parity. The disk unit reads an old parity record and generates a new value of parity record based on the read old parity and the information received from the control unit. The generated new value is stored in an empty record on the storage medium to which a read/write head is first positioned after the generation of the new value and in which effective data has not been stored. In a disk array system, a time required to update the parity record due to the updating of the data record is reduced and a performance of the storage unit subsystem is improved.
摘要:
A first storage system comprises a first logical volume, and a first controller that has a first memory. A second storage system comprises a second physical storage device that constitutes the basis of a second logical volume and a journal area, and a second controller that has a second memory. At least the first memory stores a write unit size, which is the size of a write data element. The journal area is a storage area in which is stored a journal data element, which is a data element that is stored in any block of a plurality of blocks configuring the first and/or second logical volume, or a data element that is written to this block. The size of the journal data element, and the size of the respective blocks that are managed as the respective components of the first and second logical volumes are the write unit size.
摘要:
A stator includes a stator core and a distributed winding type multi-phase coil. This coil includes unit coils made by winding a flat conductor wire in plural turns. The unit coils are mounted in slots of the stator core and connected with each other. Each unit coil includes an outer-layer coil and an inner-layer coil each being concentrically wound. Those two layer coils are made of a single continuous flat conductor wire. A winding start portion of the outer-layer coil and a winding end portion of the inner-layer coil form first and second connection end portions of the unit coil respectively. The first and second connection end portions are located separately on both edges of the unit coil above an upper end face of the stator core. The first connection end portion is placed close to an inner circumference of the stator core and the second connection end portion is placed close to an outer circumference of the stator core. The first connection end portions of the adjacent unit coils constituting the same phase are connected with each other. The second connection end portions of the adjacent unit coils constituting the same phase are connected with each other.
摘要:
A flat conductor wire in a U-phase first slot of a first group block and a flat conductor wire in a U-phase second slot of a second group block form an outer circumference base unit. A flat conductor wire in a U-phase second slot of the first group block and a flat conductor wire in the U-phase first slot of the second group block form an inner circumference base unit. The inner circumference base unit is located inside the outer circumference base unit. A coil end portion at one end of the inner circumference base unit and a coil end portion side at one end of the outer circumference base unit are bent toward the rotor side with respect to an in-slot conductor portion in the stator core. The coil end portion side at one end of the inner circumference base unit and the coil end portion side at one end of the outer circumference base unit are located further toward the axis of the rotor than an inner peripheral surface of the stator core.
摘要:
A volume provider unit in a computer system that detects a logical block address of a read or write I/O accessing a logical volume of a storage device from a host. According to the logical block address fetched, a storage domain of the logical volume is dynamically expanded. Moreover, the storage domain of the logical volume is reduced or expanded according to an instruction of logical volume capacity reduction or expansion from a host commander part to a volume server.
摘要:
Techniques to assure genuineness of data stored on a storage device are provided. The storage device includes a storage controller that conducts I/O operations and management operations. A description of management operations and corresponding timestamps are recorded to an operation log stored in a memory. The memory additionally stores an attribute for each storage volume of the storage device. Write access to each of the storage volumes is dependent on the attribute.