A memory tiering system includes a data mover device coupling a memory fabric to a processing system. At each of a plurality of different times, the data mover device receives a data access request for data from a computer context provided by the processing system, retrieves the data based on a compute-context-memory-fabric mapping that maps the compute context to the first memory subsystem, and provides the data to the processing system for use with the computer context. If the data mover device determines that the data has been retrieved and provisioning for use with the compute context above a memory tiering frequency, it moves the data from the first memory subsystem to a second memory subsystem in the memory fabric that includes higher performance memory characteristics, and causes the compute-context-memory-fabric mapping to be modified to provide a modified compute-context-memory-fabric mapping that maps the compute context to the second memory subsystem.