Patent ID: 7509342

Claim:
A file data storage management method for storing file data into a storage area divided into a plurality of blocks for real time main data storage and non-real time main data storage without pre-designation of a data storage attribute, comprising the steps of: generating a block management table for managing whether or not data are being stored in a block; generating a unit attribute table for managing an attribute of a unit containing a continuous plurality of blocks, the unit having a capacity to guarantee a read-out rate required for the file data; storing the file data based on the unit attribute table; and generating link information for determining, for file data, a link to the block used to store the file data, wherein: the unit attribute table includes information indicating a usage status of each unit and information determining whether or not real time data can be stored, the step of storing the file data comprising: in a case where the file data to be stored is the real time data, referencing the unit attribute table, searching an unused unit where the real time data can be stored, and storing the file data into the blocks corresponding to the searched unit; and in a case where the file data to be stored is non-real time data, referencing the unit attribute table, searching a unit where the non-real time data is already stored in a portion of the blocks, searching unused blocks contained in the searched unit that already contains non-real time data while referencing the block management table, and storing the file data into the unused blocks obtained by the search, and a unit capacity Usize satisfies: U size>( N× ( Tw+ ( U size/ Bhdd ))× Bsys ) where a minimum data transfer rate to/from storage means is Bhdd, a bit rate of a data stream is Bsys, a worst value of seek time in the storage means is Tw, and a number of streams processed simultaneously is N.