Writeback mechanisms for improving far memory utilization in multi-level memory architectures

Abstract

Multi-level memory architecture technologies are described. One processor includes a requesting unit, a first memory interface to couple to a far memory (FM), a second memory interface to couple to a near memory (NM) and a multi-level memory controller (MLMC) coupled to the requesting unit, the first memory interface and the second memory interface. The MLMC is to write data into a memory page of NM in response to a request from the requesting unit to retrieve the memory page from FM. The MLMC receives a hint from the requesting unit and clears a writeback bit for the memory page indicated in the hint. The hint indicates that the data contained in the memory page of the NM is not to be subsequently requested by the requesting unit. The MLMC starts a writeback operation of a memory sector including the memory page and one or more additional memory pages. The writeback operation is to transfer the data contained in the memory page from the NM to the FM when the writeback bit is set and the writeback operation does is not to transfer the data contained in the memory page from NM to the FM when the writeback bit is cleared.