DISK CACHE DATA MAINTENANCE SYSTEM

摘要

PURPOSE:To easily increase the capacity of a disk cache buffer and to improve the reusing efficiency of data in a disk cache data maintenance system of an asynchonous I/O system. CONSTITUTION:An uninterruptive power unit 5 of small capacity can supply the power to a system with no short break in a power failure state. When a power failure occurs, the contents of an asynchronous I/O disk cache buffer 31 of a main storage 3 are immediately saved in a batch saving area 41 of an external storage 4. Then the data on the area 41 are rewritten in an original user program processing file 42 and can be maintained before the operation of a user program 10 starts when a power supply is restored. Thus a battery back-up memory is not needed for maintenance of data and the buffer 31 of the same capacity as the battery back-up memory can optionally be set.