Memory systems and methods that allocate memory banks using striping size and stream identification information contained within directive commands

A method of operating a multi-bank storage device includes transmitting a write command including stream identification information to the multi-bank storage device, and allocating at least one bank, in which data associated with the write command is to be stored, from among a plurality of banks in the multi-bank storage device, based on striping size information included within the stream identification information. Upon allocation, the data is written into the allocated at least one bank.