An operation method of a storage device including first and second physical functions respectively corresponding to first and second hosts includes receiving performance information from each of the first and second hosts, setting a first weight value corresponding to the first physical function and a second weight value corresponding to the second physical function, based on the received performance information, selecting one of a first submission queue, a second submission queue, a third submission queue, and a fourth submission queue based on an aggregated value table, the first and second submission queues being managed by the first host and the third and fourth submission queues are managed by the second host, processing a command from the selected submission queue, and updating the aggregated value table based on a weight value corresponding to the processed command from among the first and second weights and input/output (I/O) information of the processed command.