Abstract: An information processing apparatus includes a storage that stores, in a state where a physical storage area in which data requested to be written to a logical storage area is to be stored without duplication is divided into a plurality of partial storage areas, each includes a plurality of unit storage areas, and where the plurality of partial storage areas are grouped in a plurality of groups, a management table in which a record associated with each of the unit storage areas is registered. The management table is divided into group regions in each of which, the records associated with the unit storage areas included in the partial storage areas belonging to the associated group among the plurality of groups are registered, each of the records contains a first hash value based on data in the associated unit storage area and location information of the associated unit storage area.

Abstract: An information processing device includes: a memory; and a processor coupled to the memory and configured to: receive an instruction to write data, executes processing to write the data to storage space of a storage device, and acquires first usage by in-use data in the storage space according to content of the write processing when the write processing has been executed; and determine setting of a space freeing-up process, based on the first usage acquired by the write processing unit and second usage by all data stored in the storage space, and executes the space freeing-up process with the determined setting.

Abstract: A control device receives a first request signal for requesting to write first data in a first logical address area of a logical volume set stores the first data in a physical volume in accordance with the first request signal, erases, after receiving the first request signal, the first data in the first logical address area of the logical volume without erasing the first data in the physical volume, and when executing a first erasure processing for erasing the first data in the physical volume, holds the first data in the physical volume, in a case where history information for indicating that a second erasure processing has been executed prior to the first erasure processing is held, and erases the first data in the physical volume, in a case where the history information is not held.

Abstract: A storage control device configured to control a storage device including a plurality of groups each of which includes a plurality of storage regions, the storage control device includes a memory and a processor coupled to the memory and configured to store, into the memory, information associated with each of the plurality of groups and indicating whether an error region in which an error is detected is included in at least one of the plurality of storage regions of each of the plurality of groups, identify a first group including the error region from the plurality of groups based on the information associated with the plurality of groups, read data from a plurality of storage regions included in the identified first group, and identify the error region included in the first group based on the read data.

Abstract: A control device receives a first request signal for requesting to write first data in a first logical address area of a logical volume set stores the first data in a physical volume in accordance with the first request signal, erases, after receiving the first request signal, the first data in the first logical address area of the logical volume without erasing the first data in the physical volume, and when executing a first erasure processing for erasing the first data in the physical volume, holds the first data in the physical volume, in a case where history information for indicating that a second erasure processing has been executed prior to the first erasure processing is held, and erases the first data in the physical volume, in a case where the history information is not held.

Abstract: In a storage control apparatus, a control unit determines whether prefetching data on a first data amount basis from a plurality of storage devices to a storage unit causes an imbalance in the numbers of commands issued to the storage devices. When determining that the prefetching causes the imbalance, the control unit prefetches the data on a second data amount basis such as to balance the numbers of commands issued to the storage devices. With this approach, the storage control apparatus creates a different imbalance of the number of read commands issued for each execution of prefetch staging, so as to prevent a fixed imbalance in which more read commands are always issued to a specific storage device.

Abstract: A storage control apparatus, that controls a storage apparatus that includes a storage drive in which a plurality of logical volumes are set, includes a storage unit that stores load information for each of the plurality of logical volumes, and a control unit that determines to-be-rebuilt volumes, which are targets to be rebuilt, from the plurality of logical volumes, sequentially selects a logical volumes for which a volume-specific taken time is estimated, determines, for each selected logical volume, a volume-specific start time at which a rebuild will be started, estimates, by using the volume-specific start time and the load information about the selected logical volume, the volume-specific taken time for rebuilding the selected logical volume, and totals the volume-specific taken time estimated for each selected logical volume to calculate a total taken time taken for rebuilding the to-be-rebuilt volumes.

Abstract: A storage control device configured to control a storage device including a plurality of groups each of which includes a plurality of storage regions, the storage control device includes a memory and a processor coupled to the memory and configured to store, into the memory, information associated with each of the plurality of groups and indicating whether an error region in which an error is detected is included in at least one of the plurality of storage regions of each of the plurality of groups, identify a first group including the error region from the plurality of groups based on the information associated with the plurality of groups, read data from a plurality of storage regions included in the identified first group, and identify the error region included in the first group based on the read data.

Abstract: A control device that controls a reading process of information stored in a unit storage area under control of the control device and a unit storage area under control of a different control device in a distributed manner, the control device includes a processor. The processor executes a procedure including determining whether or not the reading process is a sequential reading process that reads information stored in a unit storage area under control of the control device in an order of logical addresses and whether or not a reading target area of the sequential reading process includes a last address in the unit storage area, and reporting to the different control device control information related to a sequential reading process including the last address determined by the first determination unit.

Abstract: A storage control apparatus starts, in a group of storage apparatuses that store constituent data that constitute redundant data in a distributed manner in units of a stripe, in regard to respective stripes of a plurality of stripes obtained from a group of target storage apparatuses excluding one of the storage apparatuses, a plurality of rebuilding processes for restoring the constituent data; decides, for each rebuilding process, a stripe for which the rebuilding process is to be performed next, according to access loads on the respective storage apparatuses of the group of target storage apparatuses; and obtains, for each rebuilding process, constituent data corresponding to the decided stripe from the group of target storage apparatuses and executing the rebuilding process, and executes the rebuilding process, to restore constituent data stored in the excluded storage apparatus from the obtained constituent data.

Abstract: A storage control apparatus includes a controller to, when more storage devices, among a plurality of storage devices across which a plurality of information areas storing information representing redundant data and one or more spare areas are distributed, than the number of the spare areas fail, perform a rebuild process of information stored in a plurality of information areas of a failed first storage device included in the plurality of combinations of the plurality of information areas and the one or more spare areas, the rebuild process including restoring information corresponding to one information area of the failed first storage device included in one combination among the plurality of combinations, and determining a write destination storage device to which the restored information is to be written in accordance with the number of times information is read from a non-failed second storage device.

Abstract: A CM 10 includes an unmount detector 142 and a mount detector 144 that monitor unmount and mount of each disk 21 of a RAID configuration, a write request manager 143 that manages a write request for writing data to a disk 21 that is unmounted, a consistency determination unit 145 that, when mount of a disk 21 of the RAID configuration is detected, makes a determination on consistency of the data of the disk 21 in which mount is detected on the basis of the managed write request, and a RAID incorporating unit that, when it is determined that the data lacks consistency, performs processing for recovering data expected to be written by the write request issued to the disk 21 in which mount is detected while the disk 21 is unmounted and incorporates the disk 21 in an original RAID configuration.

Abstract: A storage control apparatus is communicatively connected to a storage device. The storage device includes a plurality of SSDs. The storage control apparatus includes a processing request controller and a device load detector. The device load detector detects an overload of an SSD by detecting a processing delay of the SSD. When the device load detector has detected an overload of an SSD, the processing request controller suppresses issuance of a request to process write-back with respect to a group by delaying issuance of the write-back.

Abstract: In a storage control apparatus, a control unit determines whether prefetching data on a first data amount basis from a plurality of storage devices to a storage unit causes an imbalance in the numbers of commands issued to the storage devices. When determining that the prefetching causes the imbalance, the control unit prefetches the data on a second data amount basis such as to balance the numbers of commands issued to the storage devices. With this approach, the storage control apparatus creates a different imbalance of the number of read commands issued for each execution of prefetch staging, so as to prevent a fixed imbalance in which more read commands are always issued to a specific storage device.

Abstract: A control apparatus, that controls allocation of data in a logical volume so that the data is allocated so as to span a plurality of RAID groups, according to a predetermined allocation pattern, includes a storage unit that stores correspondence information that includes at least one changing condition under which an allocation pattern for the data is changed and a new allocation pattern; and a control unit that identifies an access trend for each of the plurality of RAID groups, decides whether the logical volume satisfies the at least one changing condition, according to the correspondence information and the identified access trend, and reallocates, if the changing condition is satisfied, the data included in the logical volume according to the new allocation pattern corresponding to that changing condition.

Abstract: A storage control device includes a control unit that calculates a stripe depth and a size of padding data, when writing target data is distributed and written to respective data storages of a storage device with a RAID configuration, based on a size of the writing target data and a number of the data storages in response to a writing request to a volume on the storage device, and writes the writing target data based on the calculated stripe depth and the calculated size of the padding data.

Abstract: A system that sets a logical volume in a first physical address region of a storage device including a plurality of memory areas, receives a write request to write data to a first logical address of the logical volume, calculates a difference between a first physical address corresponding to the first logical address and a head physical address of a first memory area of the plurality of memory areas, changes, based on the calculated difference, a first physical address region of the logical volume in the storage device to a second physical address region of the storage device, and writes the data to the first logical address of the logical volume set in the second physical address region of the storage device.

Abstract: A storage control apparatus, that controls a storage apparatus that includes a storage drive in which a plurality of logical volumes are set, includes a storage unit that stores load information for each of the plurality of logical volumes, and a control unit that determines to-be-rebuilt volumes, which are targets to be rebuilt, from the plurality of logical volumes, sequentially selects a logical volumes for which a volume-specific taken time is estimated, determines, for each selected logical volume, a volume-specific start time at which a rebuild will be started, estimates, by using the volume-specific start time and the load information about the selected logical volume, the volume-specific taken time for rebuilding the selected logical volume, and totals the volume-specific taken time estimated for each selected logical volume to calculate a total taken time taken for rebuilding the to-be-rebuilt volumes.

Abstract: A storage control apparatus includes a controller to, when more storage devices, among a plurality of storage devices across which a plurality of information areas storing information representing redundant data and one or more spare areas are distributed, than the number of the spare areas fail, perform a rebuild process of information stored in a plurality of information areas of a failed first storage device included in the plurality of combinations of the plurality of information areas and the one or more spare areas, the rebuild process including restoring information corresponding to one information area of the failed first storage device included in one combination among the plurality of combinations, and determining a write destination storage device to which the restored information is to be written in accordance with the number of times information is read from a non-failed second storage device.

Abstract: A storage control apparatus starts, in a group of storage apparatuses that store constituent data that constitute redundant data in a distributed manner in units of a stripe, in regard to respective stripes of a plurality of stripes obtained from a group of target storage apparatuses excluding one of the storage apparatuses, a plurality of rebuilding processes for restoring the constituent data; decides, for each rebuilding process, a stripe for which the rebuilding process is to be performed next, according to access loads on the respective storage apparatuses of the group of target storage apparatuses; and obtains, for each rebuilding process, constituent data corresponding to the decided stripe from the group of target storage apparatuses and executing the rebuilding process, and executes the rebuilding process, to restore constituent data stored in the excluded storage apparatus from the obtained constituent data.