Patent ID: 7752397

Claim:
A method comprising: exchanging communications between a first node cluster in a multi-node system and a second node cluster in the multi-node system, each of the first node cluster and the second node cluster including: a respective set of nodes, each node in the respective set of nodes including at least a cache memory, and a respective home agent connected to the respective set of nodes; the exchanging the communications including: receiving at a first home agent a request for a block of data from a first node in the multi-node system, generating a first conflict message to send from the first home agent to initiate a first conflict phase, the generating the first conflict message in response to the first home agent receiving a conflicting request for the block of data from a second node in the multi-node system, sending from the first home agent to the first node a completion message corresponding to the request from the first node, sending, with the first node, a second conflict message to the first home agent, the second conflict message to initiate a second conflict phase, and completing the second conflict phase by providing the requested block of data to the first node and to the second node in turn; wherein the respective home agents of the first node cluster and the second node cluster are coupled to one another via a point-to-point link; and wherein one of the home agents of the first node cluster and the second node cluster operates for the communications as a proxy agent of another home agent of the multi-node system or a node of the multi-node system.