Patent ID: 8543758

Claim:
A method, comprising: relaying a first plurality of commands for a particular logical unit via a logical unit request queue (LRQ) in a channel control circuit to one of a plurality of logical unit command queues (LCQs) in an order that the first plurality of commands were received, wherein the plurality of LCQs are coupled to the LRQ and are associated with the particular logical unit; relaying a second plurality of commands for different logical units via the LRQ to those of the plurality of LCQs associated with the different logical units in an order according to a status of the different logical units; queuing, with the LRQ, a first command for a particular logical unit in response to the LCQ associated with the particular logical unit being full; receiving, with a channel request queue (CRQ) coupled to the channel control circuit, a second command from the switch and relaying the second command to the LRQ; and queuing, with the CRQ, a third command for the LRQ in response to the LRQ being full.