Patent ID: 7849369
Filing Date: 2010-12-07
Classification: G06F

Abstract:
1. A failure resistant method of operating a plurality of computers each with their corresponding independent local memory which is unable to be accessed by any other of said computers, each of said computers substantially simultaneously operating a corresponding portion of an application program written to execute on only a single computer, and each being connected via a communications network to permit updating of corresponding memory locations, said method comprising the steps of: (i) satisfying all read requests made by any one of said computers by only reading the independent local memory of the computer making the read request, wherein the independent local memory of the computer making the read request is unable to be accessed by any other of said computers, (ii) categorizing the memory locations of said local memories into a first reachability category in which the local memory locations are replicated as to contents stored in the memory locations in selected ones, or all, of said computers and therefore require updating via said communications network with changes to corresponding memory locations of the other computers to maintain substantial memory coherence, and into a second category in which the local memory locations are not replicated and are present only in the local computer and therefore no updating is required, (iii-a) detecting failure of any one of said multiple computers, and (iii-b) modifying said first category to remove therefrom, if present, any reference to the failed computer, wherein no attempt is made to update any first category locations of said failed computer.