| 摘要 |
PURPOSE:To realize a processing system high in restoration rate of environment by providing the check point data set of the data processing system with a cell which have a cell map area, and restoring old environment according to check point information. CONSTITUTION:Journal request part 10 sends a request to write check point information to a check point processor 12. A restoration processing part 11 restores the old environment in restarting on the basis of the contents of the check point data set 2 in an external storage device 1. Firstly, the request to read all effective cells is sent to the processor 12, and up-to-date check point information is extracted by kinds of information to restore the old environment. Even when an input error occurs to one piece of cell information, information restored by the structure of the set 2 only goes back to the one generation before, and the influence range of the trouble is localized. When there are requests to write from the request part 10 and processing part 11, an output processing part 13 is actuated and a cell control part 14 is requested to select which cell information is written in. The control part 14 controls cell-map cell addresses to assign cells. |
