A system may include multiple nodes, and each node may include a processing subsystem and an interface that are coupled by an address network and a data network. The nodes' interfaces may communicate over an inter-node network. Each processing subsystem may transition an access right to a coherency unit in response to a data packet on the data network and transition an ownership responsibility for the coherency unit in response to an address packet on the address network such that the access right transitions at a different time than the ownership responsibility transitions. An interface within a node may be configured to delay providing a data packet on the node's data network until the interface receives an indication that shared copies of the coherency unit in other nodes have been invalidated.
PRIORITY INFORMATION
This application claims priority to U.S. provisional application Ser. No. 60/462,010, entitled "MULTI-NODE SYSTEM WITH SPLIT OWNERSHIP AND ACCESS RIGHT COHERENCE MECHANISM", filed Apr. 11, 2003.