| 摘要 |
PURPOSE:To update logical record of a part of physical record without reading physical record to be updated from a magnetic disk by using data stored in a cache memory in case of hit. CONSTITUTION:If data stored in a cache memory 6 is hit in case of update of data of logical record of a part of physical record, a cache data reading part 5 stores read data from the memory 6 in a data storage part 4. A data writing part 2 writes data transferred from a host processor 7 and data 80 stored in the storage part 4 on a magnetic disk 8 as data of logical record to be updated and data of logical record, which should not be updated, respectively. Thus, data of logical record of a part of physical record is updated without reading physical record to be updated from the magnetic disk 8.
|
