| 摘要 |
PURPOSE:To reduce the input/output overhead for transfer of data, by referring to a storage region where the presence or absence is stored for alteration of data of a main storage device to control the transfer of information from the main storage device to an auxiliary storage device. CONSTITUTION:In the contents of an auxiliary storage cache 14 includes the contents of a main storage device 11, a CPU10 refers to a main storage data alteration information storing device 12. Then only an address is transferred via an auxiliary storage control circuit 13 if the data of the device 11 has no alteration. While both the address and data are transferred via the CPU10 to the cache 14 like a case where the cache 14 includes no data of the CPU10 if the data has an alteration. The data is written to an auxiliary storage device 17 from the chache 14 in the same way by referring to an information storage device 16 which stores the presence or absence of data of the CPU10. The input/output overhead is reduced for transfer of data, and the processing speed is increased with above-mentioned minimum necessary information transfer system. |
