Patent ID: 7818391

Claim:
A system comprising: a first node that broadcasts a request for data; and a second node having a first state associated with the data that defines the second node as an ordering point for the data, the second node providing a response to the first node that transfers the ordering point to the first node in response to the request for the data; wherein the second node transitions from the first state to a transition state associated with migration of the ordering point to the first node; wherein the first node transitions to a second state associated with the data in response to receiving the response from the second node, the second state defining the first node as the ordering point for the data; wherein the first node comprises a processor having an associated cache that comprises a plurality of cache lines, one of the cache lines having an address associated with the data, the second state identifying the one of the cache lines as the ordering point for the data in the system; and wherein the first node provides an acknowledgment signal to the second node after receiving responses from other nodes in the system.