Abstract: A computer includes a memory that stores a program and received data; and a processor that executes an operation by executing the program stored in the memory, the operation including storing the received data into a first database having a first data structure in which reading is performed in a random access manner and writing is performed in a sequential access manner, when the received data is received from a second apparatus is as same as data stored in a first apparatus which has a failure, and copying the received data stored in the first database to a second database having a second data structure in which reading is performed in a sequential access manner and writing is performed in a random access manner.

Abstract: A file server has a conversion table that stores therein, in a corresponding manner, logical addresses specified by a higher-level layer and physical addresses specified by a disk driver that are address information indicative of a storage area in a disk device. The file server accesses the disk device with a storage area indicated by a physical address as an access destination and counts up the number of access requests to each storage area in a given period of time for each of the logical addresses. The file server then updates the conversion table such that the physical addresses are lined up in a descending order of the logical addresses of a higher number of the access requests counted. Thereafter, the file server changes storage areas of data stored in the storage device based on the conversion table updated.

Abstract: Multiple storage apparatuses are provided, at least part of which are individually incorporated into one of storage groups. Each of multiple control apparatuses is configured to, when assigned one or more of the storage groups each including one or more of the storage apparatuses, control data storage by storing data designating each assigned storage group redundantly in the storage apparatuses of the assigned storage group. An information processing apparatus is configured to, when a storage group with data redundancy being lost is detected, make a change in control apparatus assignment for the storage groups in such a manner that a storage group different from the detected storage group is not assigned to a control apparatus with the detected storage group assigned thereto. Subsequently, the information processing apparatus causes the control apparatus to execute a process of restoring the data redundancy of the detected storage group.

Abstract: A replication system includes: N (?3) storage devices; and N nodes, connected to a host via a 1st network and connected to the N number of storage devices via a 2nd network, each to receive a request for accessing a storage device associated with itself and to have an access with a content in response to the received access request to the storage device, wherein when a node receives a write request of data from the host, each of M nodes (1<M<N) including the node stores the data in the storage device associated with itself, and if first data in a first storage device cannot be read out, the first data stored in another storage device is stored into a second storage device not stored with the first data by transmitting the first data via the second network.

Abstract: There are provided a processing unit that processes received requests, a storage unit that stores order information added to the last-processed request among the requests processed by the processing unit as final request information, a determination unit that determines whether the received request has been processed with reference to the final request information based on the order information added to the received request, and a control unit that, when the determination unit determines that the received request has been processed, prevents the received request from being processed by the processing unit, thereby preventing overlapped execution of a command.

Abstract: A transfer data block is selected, and a data file including the transfer data block is selected as a transfer data file. All the data blocks of the transfer data file are added to the transfer data block. When all the data files including each transfer data block is selected as a transfer data file, the transfer data block is selected as a deletion data block. When a total data amount of the deletion data block is larger than or equal to a predetermined target deletion data amount and a ratio of a total data amount of the transfer data block to the total data amount of the deletion data block is smaller than or equal to a predetermined value, the data file is transferred from a transfer source node to a transfer destination node. Accordingly, a storage can be used efficiently.

Abstract: A converting unit determines the type of data item of which data defined in a hierarchical data model is composed. When it is determined that the type of the data item is an array, the converting unit adds information obtained by binding array information, indicating an array, with order information, indicating the order of an array, to an item name of data that is defined in a non-hierarchical data model by using the item name and a value. When it is determined that the type of the data item is an object, the converting unit adds information obtained by binding object information, indicating an object, with an element to an item name. When it is determined that the type of the data item is a value, the converting unit creates data in the non-hierarchical data model by associating the value with the item name.

Abstract: An information processing system includes: CPUs; storage devices; switches; dummy storage devices which are with respective storage devices and each of which sends, when receiving an identifying information request, its own identifying information back to a sender of the identifying information request; and dummy CPUs which are associated with respective CPUs and each of which tries to, when receiving an instruction for acquiring identifying information from a dummy storage device, acquire the identifying information of the dummy storage device by transmitting the identifying information request, and sends the identifying information as response information back to a sender device of the acquiring instruction.

Abstract: A storage management apparatus manages a plurality of storage apparatuses in a storage system that disperses and stores data that is made redundant so as to have a predetermined redundancy level. The storage management apparatus includes: a patrol process unit that performs, at a patrol speed, a patrol process of confirming that the plurality of storage apparatuses are being operated normally; a relocating process unit that performs, at a relocating process speed, a relocating process of moving the data between the plurality of storage apparatuses; a recovery process unit that performs, at a recovery process speed, a recovery process of recovering the redundancy level of the data when a fault occurs in the plurality of storage apparatuses; and a processing speed control unit that controls the recovery process speed or a sum of the patrol process speed and the relocating process speed to have a predetermined value.

Abstract: In a computer for executing processing based on a storage management program, a management information storing unit designates, from the data blocks having the same content, main-data used as an access destination and sub-data used as a backup, and stores management information that registers storage nodes as allocation destinations of the respective main-data and sub-data; a load information collecting unit continuously collects load information on the storage nodes; a replacement object detecting unit detects a pair of the main-data and the sub-data having the same content and having a predetermined condition such that a load difference between the allocation destination of the main-data and that of the sub-data exceeds a predetermined allowable value; and a management information updating unit replaces roles of the main-data and the sub-data between the detected pair of data blocks.

Abstract: In a distributed storage system, client terminals make access to virtual storage areas provided as logical segments of a storage volume. Those logical segments are associated with physical segments that serve as real data storage areas. A management data storage unit stores management data describing the association between such logical segments and physical segments. Upon receipt of access requests directed to a specific access range, a segment identification unit consults the management data to identify logical segments in the specified access range and their associated physical segments. A remapping unit subdivides the identified logical segments and physical segments into logical sub-segments and physical sub-segments, respectively, and remaps the logical sub-segments to the physical sub-segments according to a predetermined remapping algorithm. A data access unit executes the access requests based on the remapped logical sub-segments and physical sub-segments.

Abstract: A computer-readable medium storing a data management program makes a computer manage data redundantly stored in storage devices having storage areas split into slices for data management. The data management program realizes the following functions in the computer. A first function receives irregularity information indicating that each of one or more of the storage devices may be possibly faulty, and stores the irregularity information in a storage; and a second function determines, by reference to the irregularity information, whether or not a first storage device containing a slice to be accessed is possibly faulty, on receipt of access information indicating occurrence of a request to access the slice. When yes is determined, the second function instructs an external device to recover data stored in the slice, where the external device controls a second storage device storing redundant data identical to the data stored in the slice.

Abstract: A computer in a disk node executes a data management program. A deduplication-eligible data unit detection module detects a data unit whose deduplication grace period after last write time has expired. A deduplication address fetch module interacts with an index server to obtain a deduplication address associated with a unique value of data stored in a constituent storage space allocated to the data unit that is found to be deduplication-eligible. A constituent storage space deallocation module stores the obtained deduplication address in a data unit record memory, together with information indicating the detected data unit. Simultaneously a constituent storage space deallocation module releases the allocated constituent storage space from the detected data unit.

Abstract: An internode put requesting unit detects a time-out with respect to a put request issued to the next node in the order of a multiplexing chain and notifies a put/get executing unit of the time-out. The put/get executing unit sends an error to the previous node in the order of the multiplexing chain or a client and instructs a put-failed-data synchronizing unit to synchronize data failed to be put, and the put-failed-data synchronizing unit performs a synchronization process. A primary makes other put requests wait until completion of the synchronization process. Furthermore, when having received the error, the client issues a get request to the tail end of the multiplexing chain.

Abstract: A storage device being one of a plurality of storage devices storing data includes a memory and a processor coupled to the memory. The processor executes determining, when having received a new request and a new priority information during a preparation for an execution of another update processing, whether a new priority indicated by the new priority information is higher than a priority of the update processing in the preparation. The process including canceling the update processing in the preparation when having determines at the determining that the new priority is higher than the priority of the update processing in the preparation. The process includes forwarding the new request and the new priority information to another storage device when having determined at the determining that the new priority is higher than the priority of the update processing in the preparation.

Abstract: A storage system having a plurality of storages. The each of the storages include a memory and a processor coupled to the memory. The processor executes a process including transmitting an update request for data which is commonly stored in the plurality of storages according to a predetermined transmission order indicating a path to transfer the update request. The process includes updating data when receiving an update request from another storage. The process includes changing the predetermined transmission order to a transmission order in which one or more storages included in the path are excluded according to the number of times the update request for the data is received.

Abstract: A storage device is one of a plurality of storage devices storing replicas of data. The storage device includes a memory and a processor coupled to the memory. The processor executes a process includes transmitting an update request to at least one destination storage device through a plurality of paths when the storage device is requested to update the data by a client. The process includes notifying the client that the updating of the data has been completed when having received a response through one of the paths, the response being issued by the destination storage device serving as the terminal point of the path when the destination storage device receives the update request through all the paths having the destination storage device as the terminal point.

Abstract: A management device obtains, from the plurality of storage nodes, information of accesses which are made to the actual storage areas included in the storage nodes, generating load information of the actual storage areas based on the access information, and storing the generated load information in a load information storage unit. The device changes, based on the load information stored in the load information storage unit, the assignment relations of the actual storage areas with respect to the virtual storage areas such that loads of the storage nodes are leveled. The device instructs the plurality of storage nodes to move the data in the actual storage areas depending on change in the assignment of the actual storage areas to the virtual storage areas.

Abstract: A computer-readable recording medium stores a program that causes a computer to execute a writing control process that includes receiving a writing request to write a first data to a first storage apparatus; determining a second data from among a series of data and based on a writing sequence of the series of data written to the computer and a count of storage areas at a second storage apparatus that sequentially selects from among the storage areas when data is received, a storage area to be over written by the received data, where the second data is written to the first storage apparatus and is identical to data that is stored in the storage area to be selected next at the second storage apparatus; and transmitting copy data of the first data to the second storage apparatus, when the second data has been written to the first storage apparatus.

Abstract: In a computer executing processes based on a storage management program, an attribute collection unit collects attributes of storage nodes. A group creation unit creates at least two groups that include the storage nodes, in accordance with the attributes of the storage nodes collected by the attribute collection unit. A data allocation unit allocates distributed data and redundant distributed data to the groups created by the group creation unit in such a manner that the distributed data and the redundant distributed data having the same content as the distributed data are placed in different groups.