Disk updating log recording system
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorHideaki Okada
Life of this patent
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Abstract
The present invention carries out a detailed log recording on a disk unit, while deteriorating effects on the disk updating performance are not increased even if the log recording is carried out accurately and in detail in order to prepare for an abrupt cease of the operation in a computer system. A log recording driver is arranged between an operating system in the computer system and disk driver. The log recording driver comprises a log recording table A which carries out log-record not so in detail but accurately, a log recording table B which carries out log-record in detail and a matching flag used for the log recording table B.
Claims14
A disk updating log recording system comprising a log recording means for managing a record of updated portion of data in a disk unit, wherein, said log recording means comprises:
- a first log recording table consisted of information areas which corresponds to a plurality of divided areas in said disk unit to record whether or not there is updating, and which is stored both in a main memory device and in the disk unit;
- a second log recording table consisted of information areas, being smaller than those of said first log recording table, which corresponds to a plurality of divided areas in said disk unit to record whether or not there is updating, which is stored in both of said main memory device and said disk unit;
- a log recording table matching flag which is stored in both of said main memory device and said disk unit for indicating whether or not said second log recording table in said main memory matches with said second log recording table in said disk unit to each other;
- a first log recording table updating means for updating said first log recording table in said main memory, and for reflecting the resultant to said first log recording table in said disk unit;
- a log recording table matching flag updating means for confirming whether or not said second log recording table in said main memory matches with said second log recording table in said disk unit according to said log recording table matching flag in said main memory, and for reflecting the resultant to said log recording table matching flag in said disk unit;
- and
- a log recording table identifying means for matching contents of said second log recording table in said main memory with those of said second log recording table in said disk unit.
Dependencies are inferred from the claim text.