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Patent Searching and Data


Title:
FAIL SAFE TYPE COMPUTER SYSTEM
Document Type and Number:
Japanese Patent JP3260433
Kind Code:
B2
Abstract:

PURPOSE: To reduce the memory capacity of an external memory device by accumulating roll-back information by distributing to the external memory device at every generation, and also switching the external memory device simultaneously when the generation is updated at a roll-back point.
CONSTITUTION: The roll-back and restart of processing can be performed by using a disk of either generation in the past even when a fault occurs in one disk by switching the disk to be designated by a memory managing unit(MHO) at every roll-back point and deciding the disk to be used at every generation. In such a case, a virtual address instructed by an EPU 1 is changed to a real address by MMO hardware 2, and the read/write of the EPU 1 on a main storage part 3 is performed. Also, when no virtual address exists on the main storage part 3, a page fault occurs, and the unrequired content of the main storage part 3 is saved once to the disk similarly as an ordinary virtual storage system, and the content of an instructed virtual address is loaded from the disk.


Inventors:
Toshio Kikuchi
Application Number:
JP21873592A
Publication Date:
February 25, 2002
Filing Date:
July 27, 1992
Export Citation:
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Assignee:
NEC
International Classes:
G06F11/14; G06F12/00; G06F12/08; G06F12/16; (IPC1-7): G06F11/14; G06F12/16
Attorney, Agent or Firm:
Naoki Kyomoto (2 outside)