The host interface module is configured to receive a plurality of I/O request which includes an associated priority; create an I/O request queue for each associated priority; define a threshold value for the queue length for each of the plurality of I/O request queues; and determine if the queue length for one of the plurality of the I/O request queue corresponding to the associated priority is less than the defined threshold value for the queue length for the one of the plurality of the I/O request queues. If the queue length of the one of the plurality of I/O request queues is more than the defined threshold value for the queue then the host interface module is further configured to rejecting the I/O request and sending a queue full message; wherein the threshold value for the queue length is based on the processing rate of the I/O requests in the plurality of the I/O request queues.