Abstract: An operation unit updates grouping information about grouping of data sets stored in a storage device, based on access information about access to data stored in the storage device and memory loading information about data loaded and held in a memory according to access to data stored in the storage device. The operation unit updates data arrangement in the storage device according to the updating of the grouping information. In the updating of the grouping information, the operation unit updates the grouping information based on relationship information between data sets according to the access information.

Abstract: A computer-readable non-transitory recording medium having stored therein a data analyzing program that causes a computer to execute a process. The process includes acquiring a transition matrix of data access based on a data access record of the data access; calculating an entropy rate for each of transition counts by using the transition matrix; determining mutual relevance of the data access based on the entropy rate; and storing data related to the data access on a disk, allocation of the data on the disk being determined by the mutual relevance of the data access.

Abstract: There is provided an information processing device includes a task executor and a controller. The task executor executes one or more second tasks that are generated by execution of a first task. The controller that controls the task executor such that the number of tasks to be executed in parallel is adjusted on the basis of a usage degree representing a degree of usage of resource in the information processing device.

Abstract: An access control method includes: in response to a first access instruction that instructs accessing first data, reading the first data and second data from a storage and deleting the first data and the second data from the storage, the first data being read from a first storage area, the second data being read from a second storage area that is physically adjacent to the first storage area and is not an empty area; and in response to a second access instruction that instructs writing third data to the storage, writing the third data to a third storage area that is adjacent to a storage area located in a physically rearmost position among storage areas in which data has been stored in the storage.

Abstract: An information processing apparatus includes a first storage device that stores in a first storage area a first data group that includes a first plurality of data to be processed successively, and stores in a second storage area a second data group that includes a second plurality of data to be processed successively, a second storage device that includes a third storage area that stores a command to access data stored in the first storage area and a fourth storage area that stores a command to access data stored in the second storage area, and a processor configured to store, in a corresponding storage area of the third storage area and the fourth storage area, a received command, select one of the third storage area and the fourth storage area, and process one or more command stored in a selected storage area.

Abstract: A computer-readable recording medium storing a program causing a processor to execute an operation, the operation includes associating a mathematical function of which a domain includes a key to uniquely specify data to be stored, with each node; associating an index value indicating an amount of the data, with each node; substituting the key in the mathematical function to calculate a value of the mathematical function; substituting the value of the mathematical function and the index value in a weighting function, of which a domain includes the value of the mathematical function and the index value, and in which a size relationship of values of the weighting function is defined in a range of the weighting function, to calculate a value of the weighting function for every node; determining a node in which the data is to be stored, based on the size relationship; and outputting the node.

Abstract: An operation unit updates grouping information about grouping of data sets stored in a storage device, based on access information about access to data stored in the storage device and memory loading information about data loaded and held in a memory according to access to data stored in the storage device. The operation unit updates data arrangement in the storage device according to the updating of the grouping information. In the updating of the grouping information, the operation unit updates the grouping information based on relationship information between data sets according to the access information.

Abstract: There is provided an information processing device includes a task executor and a controller. The task executor executes one or more second tasks that are generated by execution of a first task. The controller that controls the task executor such that the number of tasks to be executed in parallel is adjusted on the basis of a usage degree representing a degree of usage of resource in the information processing device.

Abstract: Nodes allocate auxiliary data blocks that are the backup of main data blocks to the nodes in a distributed manner. Each node that holds auxiliary data blocks stores therein management information indicating correspondences between the main data blocks corresponding to the auxiliary data blocks held by the own node and nodes holding the main data blocks.

Abstract: Each of plurality of nodes connected to each other via a network includes a local instance processor and a user application processor. The local instance processor executes a data sharing method for accessing shared data. The data sharing method includes: storing a value of first shared data with a function identifier of an update function upon receiving a registration request, wherein the update function is commutative and idempotent; updating the stored value of the first shared data to a first update value in accordance with an execution result of the update function upon receiving an update request; returning a completion message upon updating the stored value of the first shared data stored in the first node; and transmitting a first reflection request to a second node upon updating the stored value of the first shared data stored in the first node.

Abstract: When a relationship between a first data item belonging to a first group and a second data item belonging to a second group is detected, an operation unit updates the coordinates of the first data item using the coordinates of the second group and updates the coordinates of the second data item using the coordinates of the first group. The operation unit then determines which data items are to belong to each of the first and second groups, on the basis of the coordinates of the data items belonging to the first and second groups and the coordinates of the first and second groups.

Abstract: A plurality of computers dispersedly store pieces of data and pieces of depository information of the respective pieces of data. The depository information indicates a depository computer storing data of the pieces of data. A first computer of the plurality of computers stores, when depository information of first data is absent in a first storing unit of the first computer, first depository information in the first storing unit. The first depository information indicates the first computer as a first depository computer storing the first data. The first data is stored in a second storing unit of the first computer. The first computer identifies, by searching the first storing unit, a second computer as a second depository computer storing second data to be manipulated in association with third data stored in the second storing unit.

Abstract: A non-transitory computer-readable storage medium storing therein a program that causes a computer to execute a process includes managing a data processing by a processing target node among a plurality of nodes in which respective nodes have relations with other nodes, the processing target node being traced from a start node on the basis of the relations, and calculating a total number of nodes linked to the start node on the basis of numbers of stages indicating distances of processed nodes and the processing target node from the start node, and numbers of branches from the processed nodes and the processing target node, while the processing target node performs the data processing.

Abstract: A computer-readable recording medium stores a program for causing an apparatus to execute a procedure. The procedure includes: regarding each data in a data set having a key and a value corresponding to the key, calculating a key characteristic value of the data as an index value indicating an existence of the key in the data and another key included in the value based on the value of the key and the value of the other key included in the value; generating a segment in which data blocks of which the calculated key characteristic values are similar to each other are grouped in one group; and setting a storage destination of the data in the generated segment.

Abstract: A computer-readable non-transitory recording medium having stored therein a data analyzing program that causes a computer to execute a process. The process includes acquiring a transition matrix of data access based on a data access record of the data access; calculating an entropy rate for each of transition counts by using the transition matrix; determining mutual relevance of the data access based on the entropy rate; and storing data related to the data access on a disk, allocation of the data on the disk being determined by the mutual relevance of the data access.

Abstract: A data management device includes a first storage unit configured to store data; a second storage unit configured to store data, to which access is possible at a high speed compared to the first storage unit; and a processor configured to execute a process including reading, from the first storage unit or the second storage unit, data according to an input data request, and outputting the read data, analyzing relevance between data items stored in the first storage unit or the second storage unit, based on history of data requests that have been input, and dividing, into groups, the data items stored in the first storage unit or the second storage unit based on a result of the analysis, and storing, in the second storage unit, the data items in units of the groups into which the data items have been divided.

Abstract: A storage section stores segment information indicative of the correspondences between segments and keys. A control section divides, according to an increase in data which belongs to a segment, the segment into a plurality of segments and updates the segment information. In addition, the control section allows data that belongs to at least one of a plurality of second segments obtained by dividing a first segment once or by hierarchically dividing the first segment N (N>1) times, at the time of the N meeting a determined condition, to be moved from a storage device which stores data that belongs to the first segment to another storage device. The control section restricts the movement of data at the time of the N not meeting the determined condition.

Abstract: A first node is assigned a first data group, and a second node is assigned a second data group. In addition, the second node manages a backup copy of the first data group. The second node receives, from the first node, a log indicating an instruction executed on a data record belonging to the first data group, and stores the received log in a memory of the second node. The second node writes logs for a plurality of instructions accumulated in the memory into a storage device of the second node different from the memory when a predetermined condition is satisfied.

Abstract: An information processing apparatus includes a first storage device that stores in a first storage area a first data group that includes a first plurality of data to be processed successively, and stores in a second storage area a second data group that includes a second plurality of data to be processed successively, a second storage device that includes a third storage area that stores a command to access data stored in the first storage area and a fourth storage area that stores a command to access data stored in the second storage area, and a processor configured to store, in a corresponding storage area of the third storage area and the fourth storage area, a received command, select one of the third storage area and the fourth storage area, and process one or more command stored in a selected storage area.

Abstract: A clock determination method executed by a first one of apparatuses included in a system includes receiving a list including first definite clock values of respective apparatuses, the list being circulated among the apparatuses; determining the first clock value of the first apparatus at a point in time based on a smallest of logical clock values regarding corresponding commands on which processing is not completed, the commands being included in commands received by the first apparatus and the logical clock values being obtained at a time of receiving the corresponding commands and being stored, and updating the first clock value, the updated first clock value being included in the list, by using the determined first clock value; specifying, as a second clock value for the system, a smallest of the first clock values included in the updated list; and transmitting the updated list to a second one of the apparatuses.