Fujitsu Corporation

Tadaomi Kato

Mikio Ito

Riichiro Take

Yuuji Hotta

Yasuhiro Onda

Norikazu Kaiya

Hidejiro Daikokuya

Hideaki Omura

Osamu Kimura

Hiromi Kubota

A copying method, disk storage system, and storage medium for copying data from one logical disk to another logical disk, making possible immediate access, in response to a copy command. Copying from a first logical disk to a second logical disk is performed for each area in a copy range, and when there is an access to either logical disk, copying is interrupted. When performing update access of an uncopied area in the first logical disk, the area is copied from the first logical disk to the second logical disk, and then the uncopied area is updated. When performing reference access of an uncopied area in the second logical disk, the corresponding area in the first logical disk is referenced. When performing update access of an uncopied area in the second logical disk, that area in the second logical disk is updated, and copying is prohibited. In this way, it is possible to access the first and second logical disks while copying is in progress, and it is possible to immediately notify a host, upon receipt of a copy instruction, that a copying has been completed.

Copying method between logical disks, disk-storage system and its storage medium

A copying method, disk storage system, and storage medium for copying data from one logical disk to another logical disk, making possible immediate access, in response to a copy command. Copying from a first logical disk to a second logical disk is performed for each area in a copy range, and where is an access to either logical disk, copying is interrupted. When performing update access of an uncopied area in the first logical disk, the area is copied from the first logical disk to a second logical disk, and then the uncopied area is updated. When performing reference access of an uncopied area in the second logical disk, the corresponding area in the first logical disk is referenced. When performing update access of an uncopied area in the second logical disk, that area in the second logical disk is updated, and copying is prohibited. In this way, it is possible to access the first and second logical disks while copying is in progress, and it is possible to immediately notify a host, upon receipt of a copy instruction, that a copying has been completed.

An input/output scheduling unit forms input/output groups obtained by grouping inputs/outputs to/from a disk apparatus. The input/output scheduling unit defines a ratio of the time during which each input/output group uses the disk apparatus and defines quanta &tgr; to &tgr; during which each input/output group can continuously use the disk apparatus on the basis of the defined time ratios. When input/output requests are received from a plurality of input/output groups to the disk apparatus, the input/output scheduling unit performs the time-sharing for sequentially switching the allocating times &tgr; to &tgr; between the input/output groups which competed and using the disk apparatus. Further, an allocating time of the remaining quanta is distributed to the quanta on the shortage side by an allocating time control unit in accordance with a degree of jam of each input/output group.

Disk time-sharing apparatus and method

An input/output control device uses all of its cache memory effectively and allows cache memory modules to be added in increments of one. When cache memory included in the input/output control device is operating normally and the input/output control device receives a write request from a processing device, the input/output control device returns a write request completed response after writing data to cache memory as set forth in configuration information included in the input/output control device. The write data in the cache memory is then written to one or more disk devices asynchronously with the write completed response. When there is a problem with a cache memory module, the write data that was to be written to the region controlled by the cache memory module where the problem occurred is divided among the remaining cache memory modules. When adding more cache memory modules, the input/output control device writes data to the cache memory in response to a write request from a processing device based on the configuration information after the cache memory was increased and after the data was moved as set forth in the configuration information corresponding to the cache memory increase.

Disk input/output control device maintaining write data in multiple cache memory modules and method and medium thereof

A disk time-sharing apparatus is constructed by a disk apparatus having disk drives, an input/output request unit for issuing an input/output request to the disk apparatus, and an input/output scheduling unit. The input/output scheduling unit forms input/output groups obtained by grouping inputs/output sources to/from the disk apparatus, defines a ratio of time during which each input/output group uses the disk apparatus, and decides quanta (allocating time) &tgr; to &tgr; during which each input/output group can use the disk apparatus continuously on the basis of the defined time ratio. When input/output requests are received to the disk apparatus from a plurality of input/output groups, a time-sharing for using the disk apparatus by switching the allocating time &tgr; to &tgr; sequentially among the competing input/output groups is performed.

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Kawasaki, Japan

Tadaomi Kato