HIERARCHICAL MEMORY APPARATUS

Systems, apparatuses, and methods related to hierarchical memory are described. A hierarchical memory system that can leverage persistent memory to store data that is generally stored in a non-persistent memory. Logic circuitry can be configured to determine that a request to access a persistent memory device corresponds to an operation to divert data from the non-persistent memory device to the persistent memory device, generate an interrupt signal, and cause the interrupt signal to be asserted on a host coupleable to the logic circuitry as part of the operation to divert data from the non-persistent memory device to the persistent memory device. Access data and control messages can be transferred between or within a memory device, including to or from a multiplexer and/or a state machine. A state machine can include logic circuitry configured to transfer interrupt request messages to and receive interrupt request messages.