| 摘要 |
<P>PROBLEM TO BE SOLVED: To surely provide order assurance of data update by judgment of a primary data storage device. <P>SOLUTION: When writing data to a first storage medium is instructed by a host device 13-1, a cache memory managing unit of a primary data storage device 10-1 secures a cache area for storing designated data as write back data and a buffer area for transmitting the designated data to an auxiliary data storage device 10-2 in a first cache memory, and writes the data into each of them. A replication managing unit of the primary data storage device 10-1 requests unestablished write to the auxiliary data storage device 10-2 to write data stored in the buffer area to a second cache memory as unestablished write data, and requests establishing of the unestablished write data to the auxiliary data storage device 10-2 for establishing the unestablished write data already written in the second cache memory into write back data when the unestablished write data exceeds a predetermined volume. <P>COPYRIGHT: (C)2012,JPO&INPIT |
