| 摘要 |
PURPOSE:To eliminate a need of previous access and to enable access for recovery at the time of the occurrence of trouble by providing a function which detects start and end points of time of two processings which update information on a memory and store updated information in a journal and acquiring a check point without waiting for the end of a transaction which is in course of execution at the check point. CONSTITUTION:Update information is stored in a journal file 5 of a subsystem type online system, and control information on the memory at a certain point of time is saved in the check point dump file of a recovery file 4. Start and end points of time of two processings which update information on the memory and store updated information are detected by a resource management table 6, a transaction management table 7, a system status table 8 provided in a composite subsystem controller 1 and front end subsystems 2. The check point is acquired without waiting for the end of the transaction which is in course of execution at the check point. |
