05761705 is referenced by 90 patents and cites 10 patents.

Methods and associated apparatus operable in a RAID subsystem having redundant disk array controllers to assure dual, redundant cache consistency while permitting operation of the RAID subsystem in response to host computer I/O requests. The methods and apparatus of the present invention provide for a process of initializing the redundant disk array controllers in response to a power-on reset cycle (or other similar reset cycles). The first controller partially initializes for processing of host requests then awaits the partial initialization of the second controller. After a brief timeout awaiting the second controller, or in response to an erroneous initialization of the second controller, the first controller configures itself to perform host computer I/O requests in a write-through mode (bypassing cache operations) until the second controller eventually initializes. Once both controller are initialized, the redundant caches are synchronized. Finally, the initialized controllers having synchronized the redundant caches begin normal, mirrored, redundant operation. Until such time as the redundant caches are synchronized, the first controller continues operations in response to host computer I/O requests but with the degraded performance associated with the cache write-through mode.

Title
Methods and structure for maintaining cache consistency in a RAID controller having redundant caches
Application Number
8/630906
Publication Number
5761705
Application Date
April 4, 1996
Publication Date
June 2, 1998
Inventor
Max L Johnson
Wichita
KS, US
Donald R Humlicek
Wichita
KS, US
Rodney A DeKoning
Wichita
KS, US
Agent
Wayne P Bailey
Daniel L Fishman
Assignee
Symbios
CO, US
IPC
G06F 11/14
G06F 13/16
G06F 12/08
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