Nec Corporation

Takashi Torii

Masaki Kan

Satoshi Yamakawa

Yoshihiro Kajiki

Dai Kobayashi

Yoshiaki Sakae

Yasuo Itabashi

Masatsugu Ogawa

Jun Ishikawa

Masumi Ichien

Masafumi Yano

Yuji Kaneko

Michitaro Miyata

Wataru Katsurashima

An evaluation value Dfor evaluating responsiveness of a first node when no loads are being transferred, an evaluation value Dfor evaluating responsiveness of a path P connecting between the first and second nodes assuming that loads are being transferred, and an evaluation value Dfor evaluating responsiveness of the second node Nassuming that the second node has received a load from the first node are calculated. Whether or not to transfer the load is determined depending upon comparison results of magnitude of Dand a sum of D+D.

Computer network system and method of determining necessity of transferring load in computer network system

Provided a plurality of data nodes connected in a network, each including a data storage unit. The data node of data replication destination temporarily stores data to be updated in an intermediate data structure, and converts asynchronously with respect to the update request to a target data structure to store the converted data in the data storage unit. Based on access history information stored in an access history recording unit, trigger information, concerning timing for execution of conversion to the target data structure performed asynchronously by the data node is changed.

Distributed storage system and method

A distributed storage system of the present invention includes a plurality of data nodes coupled via a network and respectively including data storage units. At least two of the data nodes hold in the respective data storage units thereof replicas of a plurality of types of data structures that are logically identical but are physically different between the data nodes.

Distributed storage system and distributed storage method

To increase the reliability of power supply control of a server group and reduce the power consumption of the server group. A server includes a power supply stop control unit which stops a power supply of a predetermined processing unit upon receiving a power supply stop instruction signal instructing to stop the power supply, a power supply start-up control unit which intermittently starts up the power supply of the predetermined processing unit when the power supply stop control unit stops the power supply of the predetermined processing unit, a power supply start-up determination unit which determines whether a processing load of other servers which are executing their processes among a plurality of other servers is higher than an upper limit load determined in advance as a load required to be processed by servers the number of which is greater than or equal to the number of the other servers which are executing their processes when the power supply start-up control unit starts up the power supply of the predetermined processing unit, and a process control unit which controls process execution for the predetermined processing unit when the processing load of the other servers which are executing their processes is determined to be higher than the upper limit load.

Server, power management system, power management method, and program

A slave computer out of a plurality of slave computers that are connected to a plurality of clients through a front network and provide the front network with a single IP address that is a same IP address comprises: a responsible client table that indicates a client for which each of the plurality of slave computers is responsible; and an ARP processing unit that refers to the responsible client table when an ARP request for the single IP address has been received from one of the plurality of clients and sends an ARP response when a client that has sent the ARP request is present in the responsible client table, and otherwise does not send the ARP response, wherein a client in the responsible client table is added, changed, or deleted by a master computer connected through a back-end network.

Cluster control system, cluster control method, and program

A system includes a processing history recording means that records history information of information processing performed by an information processing means on data, a plurality of information storing means that store information in mutually different information storage formats, and an information storage format control means that controls to changes an information storage format of data, on the basis of a history of information processing performed on the data.

Information processing system and method

A system has a data structure in which a value can be obtained from a key. In a write access, a first pair &#x3c;Key,Hash(Value)&#x3e; and a second pair &#x3c;Hash(Value),Value&#x3e; are stored respectively in a volatile storage device. The first pair &#x3c;Key,Hash(Value)&#x3e; is saved in a nonvolatile storage device before returning a response, and the second pair &#x3c;Hash(Value),Value&#x3e; is saved in the first storage device at any time with the second pair saved in the volatile storage device. In a read access in which a value is obtained from a key, it is determined that data is not stored normally if the second pair is not found in processing in which after obtaining the hash value of the value from the first pair, the second pair is read.

Storage system and storage access method and program

A management policy is given to a predetermined storage area by an administrator or a predetermined end user of end users as users of a plurality of client terminals. At this time, a file server generates a setting file in which the management policy is written, to set in a directory corresponding to the predetermined storage area. A write instruction (change data) is given by the administrator or the predetermined end user. The file server changes the management policy based on the change data.

File server system and file management method using management policy and setting file to indicate management competence of storage area

A system which includes at least one client, a plurality of file servers, each having a file system, and a switch logically arranged between the client and the plurality of file servers to provide file access services which virtually render the plurality of file systems accessible as a single file system, termed a 'pseudo file system', when viewed from the terminal. The switch distributes a command that starts generation of snapshots to the plurality of file servers, which file servers formulate respective snapshots responsive to the command that starts formation of the snapshots. The switch sets the plurality of snapshots, generated by the plurality of file servers, so as to be associated with the file system structure of the virtual file system at the time of formation of the snapshots.

Switch device, system, backup method and computer program

Disclosed is a system in which an index registration unit registers an index, which will be used for search processing, as a partitioned index which is partitioned on a time series basis, and a search means reads indexes older than a specified point in time, which is used as a search base point, to perform search processing, thereby searching for information based on a point in time in the past.

Information document search system, method and program for partitioned indexes on a time series in association with a backup document storage

Disclosed is a storage management system including at least one client, a first server having a primary storage, a second server having a secondary storage, and an intermediate device logically arranged between the client and the first and second servers. The primary storage includes a stub file in which there is recorded the position information of the real file migrated from the primary storage to the secondary storage. The intermediate device exercises control so that, when a file access request of the primary storage of a first server, issued by the client, is received by the intermediate device, the intermediate device receives the file access request and, if the file to be accessed is a stub file, and the access request necessitates accessing to the real file, the intermediate device accesses the real file of the secondary storage using the information of the stub file to return a response.

Storage management system and method and program

Each of the sites interconnected to one another through a wide area network includes at least one client, a switch device logically disposed between the client and at least one server including a storage device, for providing to the client a file access virtually unifying of a plurality of storage devices, and an analysis device connected to the switch device. The switch device takes log information on the file access from the client. The analysis device determines data to be migrated to the server in a site to which the client belongs or the server in a site in vicinity of the site to which the client belongs, and commands the switch device to migrate the data. The switch device migrates the data based on the command from the analysis device.

System and method for managing and arranging data based on an analysis of types of file access operations

A switch device has an object ID rewrite unit and a file access control unit. The object ID rewrite unit, when an original object ID is contained in a reply to be transferred, rewrites the original object ID to an information entraining object ID by inserting server identification information into the original object ID, while when the information entraining object ID is contained in a reply to be transferred, restores the information entraining object ID to the original object ID. The file access control unit includes a table for managing a combination of address information of a server and server identification information, estimating address information of a server corresponding to server identification information contained in an information entraining object of a request to be transferred with reference to the table, and determines a destination of the request on the basis of the address information.

Switching method and switch device

An intermediate device which can be introduced and removed in seamless way is disclosed. The state information acquiring means acquires state information required to maintain the state of a session established between the first information processing device and the second information processing device for the information processing service, from the first information processing device or the second information processing device. The intermediate service managing means generates, based on the state information, transfer rules for applying the intermediate service to data of the information processing service, and transferring the data to which the intermediate service is applied. The transfer control means maintains the state of the existing session between itself and the second information processing device, establishes a new session between itself and the first information processing device, and transfers the data using the existing session and the new session, according to the transfer rules.

Growing community of inventors

Tokyo, Japan

Takashi Torii