Cache coherency management for multi-category memories

A method comprising:

• receiving a first request including an address of a first memory block in a shared memory and instructions relating to the first memory block,
• wherein the shared memory includes a plurality of memory blocks of one or more memory devices, and each of the plurality of memory blocks is associated with one of a plurality of memory categories indicating a protocol for managing cache coherency for the respective memory block;
• determining a memory category associated with the first memory block;
• and
• transmitting a response to the first request based on the memory category of the first memory block,
• wherein the first memory block is included in one of the memory devices, the one of the memory devices further including at least a second memory block of a memory category different than the memory category of the first memory block.

A system, comprising:

• one or more node controllers;
• and
• a plurality of processors and corresponding memories, wherein each of the plurality of the processors and corresponding memories are associated with and local to one of the node controllers, the memories forming a shared memory,
• wherein each of the one or more node controllers is configured to:
• store a directory including state and ownership information of memory blocks of the local memories;
• and
• store a directory cache including state information of other memory blocks of the local memories,
• wherein the state and ownership information of the other memory blocks of the local memories is not stored in the directory.