In a data storage system having a drive I/O command queue associated with a data storage device, contiguous I/O requests of at least a predetermined size may be processed in a pipeline mode of operation by issuing to the command queue a plurality of contiguous I/O request portions, each comprising a portion of the I/O request, so that a next one of the I/O request portions is in the command queue before the data storage system completes a current I/O request portion. The data storage device may implement I/O reordering based on data location and contain at least two device I/O command queues or, alternatively, may not implement such reordering and contain a single command queue. In one embodiment, a performance parameter of the data storage system, such as the bandwidth requirement for the contiguous I/O request, is monitored and the size of subsequent I/O request portions and/or the state of the pipeline mode of operation are adjusted accordingly. With this arrangement, large contiguous I/O requests can be executed at a higher bandwidth, without adversely impacting other I/O requests for the same device.