Abstract: A fragmentation information collecting section in a file system control section collects fragmentation information on a target volume for which a fragmentation state is to be eliminated, the target volume being managed by a file system. An analysis section in the file system control section analyzes the fragmentation state of the target volume on the basis of the fragmentation information collected, to generate block rearrangement information required to eliminate the fragmentation state of the target volume. A block rearrangement command generating section in the file system control section generates a block rearrangement command row corresponding to the block rearrangement information. A disk array control device executes the block rearrangement command row to eliminate the fragmentation state of the target volume.

Abstract: A fragmentation information collecting section in a file system control section collects fragmentation information on a target volume for which a fragmentation state is to be eliminated, the target volume being managed by a file system. An analysis section in the file system control section analyzes the fragmentation state of the target volume on the basis of the fragmentation information collected, to generate block rearrangement information required to eliminate the fragmentation state of the target volume. A block rearrangement command generating section in the file system control section generates a block rearrangement command row corresponding to the block rearrangement information. A disk array control device executes the block rearrangement command row to eliminate the fragmentation state of the target volume.

Abstract: An information communication system for performing information communication between a first system and a second system is disclosed. The communication system includes a first communication path that is used for information communication when a transfer size between the first system and the second system is smaller than a predetermined size and is capable of high-speed response, and a second communication path that is used for information communication when the transfer size between the first system and the second system is larger than the predetermined size and has a larger transfer capability than that of the first communication path. Each of the first and second systems comprises main control means for selectively using one of the first and second communication paths in accordance with a size of information subjected to information communication with a counterpart system.

Abstract: If one of the HDDs of a disk array fails, a disk array controller regenerates the data stored in the failed HDD and stores the regenerated data in another HDD used in place of the failed HDD. To be more specific, the disk array controller checks each of the stripes of the disk areas of the disk array and determines whether each stripe is used by a file system. This determination is based on a disk resource management table. Then, the disk array controller regenerates data by use of RAID technology only for a stripe that has been determined as being used by the file system.

Abstract: A recording medium and a recoding medium master, and a method of manufacturing the recording medium which comply with the standard of recording/reproducing characteristic established in the MD standard while enabling precise discrimination of the pit track and groove track and optical detection of the pits by optical pickup and the like are provided. Pits and grooves are arranged on a surface of a disc-shaped substrate so as to form a grooves and the ratio is from 1.00 exclusive to 1.13 inclusive. It is preferable that the track pitch of the grooves is from 1.50 &mgr;m inclusive to 1.70 &mgr;m exclusive. The width of the pits and grooves in the radial direction of the substrate is the same.

Abstract: If one of the HDDs of a disk array fails, a disk array controller regenerates the data stored in the failed HDD and stores the regenerated data in another HDD used in place of the failed HDD. To be more specific, the disk array controller checks each of the stripes of the disk areas of the disk array and determines whether each stripe is used by a file system. This determination is based on a disk resource management table. Then, the disk array controller regenerates data by use of RAID technology only for a stripe that has been determined as being used by the file system.

Abstract: A recording medium and a recoding medium master, and a method of manufacturing the recording medium which comply with the standard of recording/reproducing characteristic established in the MD standard while enabling precise discrimination of the pit track and groove track and optical detection of the pits by optical pickup and the like are provided. Pits and grooves are arranged on a surface of a disc-shaped substrate so as to form a grooves and the ratio is from 1.00 exclusive to 1.13 inclusive. It is preferable that the track pitch of the grooves is from 1.50 &mgr;m inclusive to 1.70 &mgr;m exclusive. The width of the pits and grooves in the radial direction of the substrate is the same.

Abstract: The shared disk array which incorporates a plurality of disk apparatus storing the contents including the digitized video data and a plurality of element servers are connected to the shared channel network suitable for the multi-initiator architecture, whereby each of the element servers can physically share the shared disk array via the shared channel network. Further, each of the element servers is provided with the network interface suitable for the high-speed transmission and the band-width reservation, so that the contents stored in the shared disk array are read out in response to the request form the client, thus being output of the communication network via the network interface.