Trouble recovery system

Abstract

Abstract PURPOSE:To obtain a high-speed trouble recovery system of less log quantity, by using the backup version/current version system for a page table and a volume slot map and using a differential file system for volume slots. CONSTITUTION:A data processing device is provided with a volume slot VSV which is a set of physical pages for storage of data, a current-version page tabel PC where the correspondence between logical pages and physical pages at the current time is indicated, a current-version VS map MC where use conditions of physical pages of the volume slot VSV are indicated, a backup-version page table PB which has the same contents as the table PC at the time point of the compeltion of a check point processing, a backup-version VS map MB which has the same contents as the map MC at the time point of the completion of a check point processing, and a log file L consisting of plural log blocks LB. Since the page table PB and the map MB are held as backup versions of the page table PC and the map MC, the page table PC and the map MC can be returned to states of the page table PB and the map MB. Though the differential file system is used for the volume slot VSV, no extra files are required because it is mixed with main files.

Inventors

• 👤 Yoshio Izumida
• 👤 泉田　義男
• 👤 Hideki Sato
• 👤 秀樹 佐藤
• 👤 Teruo Nakada
• 👤 中田　輝生

Bibliographic Details