Patent ID: 7412555
Filing Date: 2008-08-12
Classification: G06F

Abstract:
1. A controller comprising: one or more transaction queues storing, during use, a plurality of transaction requests, each of the plurality of transaction requests having a transaction type; one or more age counter circuits generating, during use, one or more age counters, each of the age counters corresponding to a respective pair of transaction types; and a control circuit coupled to receive an indication of an input transaction type corresponding to an input transaction request to the controller and coupled to the one or more age counter circuits, wherein the control circuit selects at least one of the one or more age counters to be stored with the input transaction request in the one or more transaction queues, each of the at least one selected counters indicative of a relative age of the input transaction request with transaction requests of another transaction type, and wherein the control circuit conditionally causes, during use, an update of a first age counter for which the corresponding pair includes the input transaction type, wherein the control circuit does not cause the update responsive to the input transaction type being the same as the most recent transaction type of the corresponding pair, regardless of which of the corresponding pair is the input transaction type.