A method, computer program product, and computer system for receiving, by a computing device, an I/O request for data. A number of storage devices of a plurality of storage devices in a Mapped RAID group that will be used to process the I/O request may be determined. It may be determined whether each storage device of the number of storage devices in the Mapped RAID group that will be used to process the I/O request has a respective threshold number of credits to process the I/O request. If each storage device of the number of storage devices in the Mapped RAID group that will be used to process the I/O request has the respective threshold number of credits, the I/O request may be processed. If at least one storage device of the number of storage devices in the Mapped RAID group that will be used to process the I/O request lacks the respective threshold number of credits, the I/O request may be queued.