Methods of operating an electronic system include allocating a group of memory cells of a plurality of groups of memory cells having a particular rank of a plurality of ranks for storing data of a particular data level of a plurality of data levels, determining a need for an additional group of memory cells for storing data of the particular data level, moving or discarding data from a different group of memory cells storing data of a different data level of the plurality of data levels in response to determining the need for the additional group of memory cells for storing data of the particular data level, and allocating the different group of memory cells for storing data of the particular data level.