1. A memory module, comprising: a plurality of sub-stacks including memory devices of a first type, each sub-stack comprising: a respective plurality of memory devices of the first type; and a respective sub-controller configured to control the respective plurality of memory devices of the first type; a super-controller configured to control each of the sub-controllers of the plurality of sub-stacks; and a host interface coupled to the super-controller and configured to transmit data to a memory controller.