Abstract: A distributed object management system includes: a completion information management portion which stores a relay state of the object server and which manages information of the object which should be transmitted again when the transmission to the object server is resumed; and a relay control portion which requests other object server to temporally exclude the object server that has transmitted the suspension request from a copying operation of the object and which, if the resume request is received from the object server that has transmitted the suspension request, requests said other object server to include the object server that has transmitted the resume request in the copying operation of the object again.

Abstract: Provided is a data supply apparatus including a transmission device that sends data to another data supply apparatus; a reception device that receives data from another data supply apparatus; a data storing device that stores data in a storage device; and a data storage determination device that determines whether or not the received data should be stored in the storage device, based on a predetermined supply probability. In a typical example, the reception device receives the data to which supply probability information which indicates the supply probability has been appended; and the data storage determination device determines whether or not the received data should be stored in the storage device, based on the supply probability indicated by the supply probability information.

Abstract: Provided is a data supply apparatus including a transmission device that sends data to another data supply apparatus; a reception device that receives data from another data supply apparatus; a data storing device that stores data in a storage device; and a data storage determination device that determines whether or not the received data should be stored in the storage device, based on a predetermined supply probability. In a typical example, the reception device receives the data to which supply probability information which indicates the supply probability has been appended; and the data storage determination device determines whether or not the received data should be stored in the storage device, based on the supply probability indicated by the supply probability information.

Abstract: A distributed object management system includes: a completion information management portion which stores a relay state of the object server and which manages information of the object which should be transmitted again when the transmission to the object server is resumed; and a relay control portion which requests other object server to temporally exclude the object server that has transmitted the suspension request from a copying operation of the object and which, if the resume request is received from the object server that has transmitted the suspension request, requests said other object server to include the object server that has transmitted the resume request in the copying operation of the object again.

Abstract: In a distributed file system, the load of a meta server, and communications traffic between a client and the meta server is reduced. Specifically, each of a plurality of clients is provided with an object position calculating section and an arrangement algorithm storage section, and acquires the meta data from the meta server, and determines the objects and the storage positions of the objects (e.g. the object server IDs) through calculation on the side of the client by using an arrangement algorithm ID, the arrangement parameter corresponding to the file which is contained in the meta data.

Abstract: A file management system and the like for alleviating the load on the hardware due to file synchronization are provided. A file management system includes a time measurement unit for recording an update history of the file; an update interval calculation unit for calculating an update interval and a blank period of the file based on the update history, and determining a synchronization time of the file based on the update interval and the blank period; and a file management unit for executing synchronization of the file stored in the plurality of storage media at the synchronization time.

Abstract: A data recording/reproduction apparatus classifies each request into any one of a real-time processing data request, a metadata request, and a non-real-time data request and accumulates each classified request. A request readout device in the apparatus sequentially reads out each accumulated input/output request in accordance with a predetermined reference time. In order to attain a desired data rate of the real-time processing data, the request readout device delays reading out a metadata request for a fixed period specified by the reference time. A processing of delayed metadata input/output request collectively is executed with a subsequent processing metadata input/output request.

Abstract: A data recording/reproduction apparatus classifies each request into any one of a real-time processing data request, a metadata request, and a non-real-time data request and accumulates each classified request. A request readout device in the apparatus sequentially reads out each accumulated input/output request in accordance with a predetermined reference time. In order to attain a desired data rate of the real-time processing data, the request readout device delays reading out a metadata request for a fixed period specified by the reference time. A processing of delayed metadata input/output request collectively is executed with a subsequent processing metadata input/output request.

Abstract: A data storage device is provided which stores audio/video data to a disk media with a small amount of buffer memory and improves response with a reduced cost. Data transmission timing is known from a DMA request signal (DREQ) and a DMA acknowledgement signal (DACK). Therefore, audio/video data from an encoder can be directly supplied to an interface device without being temporarily stored in a buffer memory located before the interface device.

Abstract: The present invention provides an input-output interface connected via an input-output bus to a host computer and connected with at least one memory device. The input-output interface includes a bus interface control section, an input-output control section and an additional feature for determining tie order of input-output operations not only in accordance with informations externally received about the time limitation thereof or informations externally received about until when the data processing should be completed but also in accordance with priorities determined by itself with reference to the above information so as to obtain the input-output operations within the time limitation.