Enhanced protection for memory modification tracking with...

Electrical computers and digital processing systems: memory – Storage accessing and control – Hierarchical memories

Reexamination Certificate

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Details

C711S145000, C711S120000, C711S162000, C714S006130, C714S013000

Reexamination Certificate

active

06950907

ABSTRACT:
A dirty memory subsystem includes storage operable to store redundant copies of dirty indicators. Each dirty indicator is associated with a respective block of main memory and is settable to a predetermined state to indicate that the block of main memory associated therewith has been dirtied. By providing redundant storage for the dirty indicators, any difference between the stored copies of the dirty indicators can be considered as indicative of memory corruption, for example as a result of a cosmic ray impact. As the different copies can be stored in different locations, it is unlikely that a cosmic ray impact would affect all copies equally. If a difference between the stored copies is detected, then the dirty indicator can be take as being unreliable and remedial action can be taken. For example, it can be assumed that a block of main memory has been dirtied if any of the copies of the dirty indicator has the predetermined state. Such a memory finds application in a method of managing reinstatement of an equivalent memory state in the main memory of a plurality of processing sets of a fault tolerant computer following a lock step error.

REFERENCES:
patent: 5166883 (1992-11-01), Gilham
patent: 5276899 (1994-01-01), Necker
patent: 5301287 (1994-04-01), Herrell et al.
patent: 5553266 (1996-09-01), Metzger et al.
patent: 5692150 (1997-11-01), Moriyama et al.
patent: 5790776 (1998-08-01), Sonnier et al.
patent: 5838894 (1998-11-01), Horst
patent: 5845298 (1998-12-01), O'Connor et al.
patent: 5895485 (1999-04-01), Loechel et al.
patent: 5953742 (1999-09-01), Williams
patent: 5987544 (1999-11-01), Bannon et al.
patent: 5991900 (1999-11-01), Garnett
patent: 6047392 (2000-04-01), Liddell et al.
patent: 6138198 (2000-10-01), Garnett et al.
patent: 6141766 (2000-10-01), Liddell et al.
patent: 6148348 (2000-11-01), Garnett et al.
patent: 6151689 (2000-11-01), Garcia et al.
patent: 6167477 (2000-12-01), Garnett et al.
patent: 6233702 (2001-05-01), Horst et al.
patent: 6260159 (2001-07-01), Garnett et al.
patent: 6272033 (2001-08-01), Watt
patent: 6289022 (2001-09-01), Gale et al.
patent: 6496940 (2002-12-01), Horst et al.
patent: 6622219 (2003-09-01), Tremblay et al.
patent: 6640287 (2003-10-01), Gharachorloo et al.
patent: 6782453 (2004-08-01), Keltcher et al.
patent: 6785763 (2004-08-01), Garnett et al.
patent: 6785777 (2004-08-01), Garnett et al.
patent: 2002/0065996 (2002-05-01), Garnett et al.
patent: 2002/0066049 (2002-05-01), Garnett et al.
patent: 2003/0182492 (2003-09-01), Watkins et al.
patent: 2003/0182594 (2003-09-01), Watkins et al.
patent: WO 9966416 (1999-12-01), None
UK Combined Search and Examination Report, application No. GB0029103.9, filed Nov. 29, 2000.

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