Abstract: The file storage system includes a controller and a volume storing a plurality of files, the volume including a first directory storing a first file and a second file and a second directory storing a third file being created. The controller migrates actual data of the second file to the third file, sets up a management information of the second file so that the third file is referred to when the second file is read, and if the sizes of actual data of the first file and the actual data of the third file are identical and the binaries of the actual data of the first file and the actual data of the third file are identical, sets up a management information of the first file to refer to the third file when reading the first file.

Abstract: An electromagnetic flowmeter using a square wave excitation method includes a differential amplifier which outputs a detection signal; an analog-digital converter which converts the detection signal into a digital detection signal; a timing control circuit which generates a sampling signal for sampling the digital detection signal; an calculation unit which executes a flow rate calculation process and a abnormality judging process at a same time. The flow rate calculation process acquires a flow velocity output signal by sampling the digital detection signal in a flat portion in a positive/negative excitation section.

Abstract: In the prior art clone creating technique of a file, a management table of a snapshot and the file was created when creating the clone file, so that a considerable amount of creation time for creating the clone file and storage capacity was required. In order to solve the problems of the prior art, the present invention provides a system wherein if a request to create a clone of a file is received, a differential file is created while inhibiting update of the file, and update data is written to the differential file. Further, when a first update request is received to the differential file after creating the differential file, a management table is created. According to the invention, a large amount of clone files can be created speedily.

Abstract: A storage system 103 carries out first and second de-duplication processes in response to receiving a write request from a client. First, a determination is made as to whether a write target data item overlaps with any of the stored data items of a part of a stored data item group, which is a user data item group stored in a storage device 209, and if so, the write target data item is prevented from being stored in the storage device. Second, a determination is made as to whether a target stored data item, which is not finished being evaluated as to whether it overlaps with the stored data item in the first de-duplication process, overlaps with another stored data item, and if so, the target stored data item or the same data item overlapping with the target stored data item is deleted from the storage device 209.

Abstract: Management apparatus and method to prevent a drop in the service quality of data. In a computer system which replicates and holds data which is stored in a storage apparatus by a communication terminal in other storage apparatuses, physical position information of the storage apparatuses and the communication terminal is collected and, at the time of the disaster recovery processing, a storage apparatus for which the data of the secondary system is to be switched to the primary system is selected from among the storage apparatuses which hold the data of the secondary system on the basis of physical position information in a first predetermined period among the collected physical position information of the communication terminal, and a policy preconfigured for the data, and an instruction is issued to the selected storage apparatus to switch the data of the secondary system held by the storage apparatus to the primary system.

Abstract: An aspect of this invention is a computer system, including: a storage apparatus for allocating real storage areas of a plurality of tiers of a tiered real storage area pool to a volume, and migrating and relocating data within the volume between the plurality of tiers; and a host apparatus that accesses the volume provided by the storage apparatus. The host apparatus is configured to refer to tier information including information on a corresponding one of the plurality of tiers to which an access destination address within the volume belongs to identify the corresponding one of the plurality of tiers to which the access destination address belongs and refer to settings predetermined for the plurality of tiers to perform I/O control for the access destination address based on settings of the identified corresponding one of the plurality of tiers.

Abstract: In the prior art clone creating technique of a file, a management table of a snapshot and the file was created when creating the clone file, so that a considerable amount of creation time for creating the clone file and storage capacity was required. In order to solve the problems of the prior art, the present invention provides a system wherein if a request to create a clone of a file is received, a differential file is created while inhibiting update of the file, and update data is written to the differential file. Further, when a first update request is received to the differential file after creating the differential file, a management table is created. According to the invention, a large amount of clone files can be created speedily.

Abstract: In the prior art clone creating technique of a file, a management table of a snapshot and the file was created when creating the clone file, so that a considerable amount of creation time for creating the clone file and storage capacity was required. In order to solve the problems of the prior art, the present invention provides a system wherein if a request to create a clone of a file is received, a differential file is created while inhibiting update of the file, and update data is written to the differential file. Further, when a first update request is received to the differential file after creating the differential file, a management table is created. According to the invention, a large amount of clone files can be created speedily.

Abstract: A NAS device providing a snapshot function for executing CoW processing in multiple successive block units is provided, wherein upon restoring a file saved in a file system sharing from a snapshot, the speed for restoring files is enhanced by restoring only data blocks that have been changed within the data blocks constituting a file, to thereby reduce the amount of data being restored and cut down CoW processing. Upon restoring a file stored in file system sharing from a snapshot file, data blocks storing different data between the restore source file and the restore destination file are specified based on a differential map table and a differential block table, and only the specified data blocks are restored. Further, upon restoring data from a file other than the snapshot, the data blocks constituting the restore source file and the restore destination file are compared, and only the data blocks storing different data are restored.

Abstract: A file server performs duplicate elimination on files, and creates a virtual file system that does not include a duplicate file and is used for creating a search index. A search server acquires search target files from the virtual file system in the file server, and creates the search index.

Abstract: The file storage system includes a controller and a volume storing a plurality of files, the volume including a first directory storing a first file and a second file and a second directory storing a third file being created. The controller migrates actual data of the second file to the third file, sets up a management information of the second file so that the third file is referred to when the second file is read, and if the sizes of actual data of the first file and the actual data of the third file are identical and the binaries of the actual data of the first file and the actual data of the third file are identical, sets up a management information of the first file to refer to the third file when reading the first file.

Abstract: A method and a storage system are provided for implementing a sustained large block random write performance mechanism for shingled magnetic recording (SMR) drives in a redundant array of inexpensive disks (RAID). A Solid State Drive (SSD) is provided with the SMR drives in the RAID. The SSD is used in a hot spare mode, which is activated when a large block random-write event is identified for a SMR drive in the RAID. In the hot spare mode, the SSD temporarily receives new incoming writes for the identified SMR drive. Then the identified SMR drive is updated from the SSD to restore the state of the identified SMR drive, and operations continue with normal writing only using the SMR drives in the RAID.

Abstract: Root node arrangements configured to carry out file level virtualization for logically providing a plurality of share units that can be shared among file systems of the root node or other one or more root nodes, to a client.

Abstract: Management apparatus and method to prevent a drop in the service quality of data. In a computer system which replicates and holds data which is stored in a storage apparatus by a communication terminal in other storage apparatuses, physical position information of the storage apparatuses and the communication terminal is collected and, at the time of the disaster recovery processing, a storage apparatus for which the data of the secondary system is to be switched to the primary system is selected from among the storage apparatuses which hold the data of the secondary system on the basis of physical position information in a first predetermined period among the collected physical position information of the communication terminal, and a policy preconfigured for the data, and an instruction is issued to the selected storage apparatus to switch the data of the secondary system held by the storage apparatus to the primary system.

Abstract: In file de-duplication using hash value comparison, hash values of all target files must be calculated and actual data of all files must be read for hash value calculation, so that the processing time was long. The present invention provides a file storage system comprising a controller and a volume storing a plurality of files, the volume including a first directory storing a first file and a second file and a second directory storing a third file being created, wherein the controller migrates actual data of the second file to the third file, sets up a management information of the second file so that the third file is referred to when the second file is read, and if the sizes of actual data of the first file and the actual data of the third file are identical and the binaries of the actual data of the first file and the actual data of the third file are identical, sets up a management information of the first file to refer to the third file when reading the first file.

Abstract: A storage system 103 carries out first and second de-duplication processes in response to receiving a write request from a client. First, a determination is made as to whether a write target data item overlaps with any of the stored data items of a part of a stored data item group, which is a user data item group stored in a storage device 209, and if so, the write target data item is prevented from being stored in the storage device. Second, a determination is made as to whether a target stored data item, which is not finished being evaluated as to whether it overlaps with the stored data item in the first de-duplication process, overlaps with another stored data item, and if so, the target stored data item or the same data item overlapping with the target stored data item is deleted from the storage device 209.

Abstract: A storage system 103 carries out first and second de-duplication processes in response to receiving a write request from a client. First, a determination is made as to whether a write target data item overlaps with any of the stored data items of a part of a stored data item group, which is a user data item group stored in a storage device 209, and if so, the write target data item is prevented from being stored in the storage device. Second, a determination is made as to whether a target stored data item, which is not finished being evaluated as to whether it overlaps with the stored data item in the first de-duplication process, overlaps with another stored data item, and if so, the target stored data item or the same data item overlapping with the target stored data item is deleted from the storage device 209.

Abstract: Provided is a storage system capable of saving actually used physical storage areas and of achieving a high speed in write processing. There is disclosed a computer system including a server and a storage system, in which physical storage areas of a disk drive are managed for each one or more physical blocks of predetermined sizes, and allocation of one or more physical blocks to a plurality of logical blocks of predetermined sizes is managed, and the storage system stores data written in a first logical block in a first physical block allocated to the first logical block and allocates the first physical block to a second logical block where the same data as the data stored in the first physical block is to be written.

Abstract: Difference information between two snapshots from a first point-in-time snapshot, which has been copied, to an N.sup.th point-in-time snapshot, which constitutes the latest point-in-time snapshot, is acquired to a memory module. The memory module stores two or more pieces of difference information. The two or more pieces of difference information comprise difference information that shows the difference between a first point-in-time snapshot and any snapshot other than the first point-in-time snapshot of N snapshots. Copy difference information, which is information that shows the difference between the first point-in-time snapshot and a specified snapshot from among N snapshots, and which is used in copying the specified snapshot, is created on the basis of the two or more pieces of difference information.

Abstract: A NAS device providing a snapshot function for executing CoW processing in multiple successive block units is provided, wherein upon restoring a file saved in a file system sharing from a snapshot, the speed for restoring files is enhanced by restoring only data blocks that have been changed within the data blocks constituting a file, to thereby reduce the amount of data being restored and cut down CoW processing. Upon restoring a file stored in file system sharing from a snapshot file, data blocks storing different data between the restore source file and the restore destination file are specified based on a differential map table and a differential block table, and only the specified data blocks are restored. Further, upon restoring data from a file other than the snapshot, the data blocks constituting the restore source file and the restore destination file are compared, and only the data blocks storing different data are restored.