Patent ID: 6948035
Filing Date: 2005-09-20
Classification: G06F

Abstract:
1. A node comprising: an interconnect; a transaction initiating circuitry coupled to the interconnect to initiate a transaction on the interconnect, the transaction addressing a cache coherent block of data in which a transaction identifier is associated with the transaction; and a memory bridge coupled to the interconnect and to interface circuits that communicate with other nodes, the memory bridge including a directory to track local cache blocks residing in remote nodes and a control circuit coupled to provide a response to the transaction on the interconnect, in which the response is indicative of a state of the cache coherent block in one or more of the remote nodes identified by the directory, wherein the bridge circuit to cause the transaction to become globally visible to the remote nodes by sending a probe identifying the transaction and in return receiving an acknowledgement from the remote node or nodes having the cache coherent block when the transaction is made visible to the remote nodes, the transaction initiating circuitry to pend completing the transaction until the memory bridge receives the acknowledgment from the remote node or nodes and, upon completion of receiving the acknowledgement or acknowledgements, the control circuit transmits a signal, that includes the transaction identifier, to the transaction initiating circuitry that the transaction affecting the coherent cache block is allowed to be completed.