Patent ID: 7552247

Claim:
Apparatus for maintaining ordering of transaction data in relation to completion of transactions while the transaction data are processed, the transaction data being issued from at least one peripheral computer device which issues the transactions, the transactions being associated with multiple processor systems, the multiple processor systems together utilizing at least two processors associated with a computer memory system, the apparatus comprising: memory control means operatively connected to each of said processors, the computer memory system and the at least one peripheral computer devices; queuing means for queuing a first data write transaction issued by the at least one peripheral computer devices; tagging means for determining whether the first data write transaction is complete, for tracking a sequence order of the first data write transaction relative to a second data write transaction also queued by the queuing means, for causing second write data associated with the second data write transaction to be processed and first write data associated with the first data write transaction to be processed using the memory control means; and, means for outputting the first write data as has been processed, and then thereafter for outputting the second write data as has been processed only upon completion of the first data write transaction, wherein the second write data is processed before with the first write data while still ensuring that the second write data is output in correct order in relation to the first write data, wherein one or more invalidates for the first data write transaction are issued in parallel with one or more invalidates for the second data write transaction, and wherein the second data write transaction is not visible until the invalidates for the first data write transaction have been received.