Patent ID: 7702743

Claim:
A system comprising: a plurality of computers coupled to a network, wherein each of the plurality of computers comprises one or more software modules which, when executed on the computer, present resources of the plurality of computers as a virtual machine; wherein the virtual machine is a non-uniform memory access (NUMA) machine comprising a plurality of nodes, each node having memory that is part of a distributed shared memory, and wherein the virtual machine is coherent with a weakly ordered memory model; and wherein the one or more software modules, are executable in a current owner node of a first block in response to an ownership transfer request from a requesting node of the plurality of nodes for the first block, wherein the ownership transfer request is a request to transfer ownership of the first block from the current owner node to the requesting node, wherein the one or more software modules, when executed: determine that the first block has been modified in the current owner node; and perform a synchronization operation in response to determining that the first block is modified in the current owner node, wherein the synchronization operation comprises determining each other modified block in the memory of the current owner node and wherein the synchronization operation further comprises writing the first block to a home node of the first block and writing each other modified block in the current owner node to the home node of that modified block in response to detecting that the first block is modified in the current owner node and wherein the first block and each modified block is stored in a separate memory location in the memory of the respective home node of that block.