Location-based global cache tiering

A computing device, comprising:

• a memory;
• and
• at least one processor that is operatively coupled to the memory, the at least one processor being configured to perform the operations of:
• generating or updating a cache metadata table that identifies a plurality of cache slots, for each of the plurality of cache slots, the cache metadata table including a different respective location identifier that indicates a location for that cache slot;
• receiving an I/O request that is associated with a logical block address;
• allocating a given one of the plurality of cache slots to the logical block address based on the respective location identifier that corresponds to the given cache slot;
• and
• executing the I/O request by using the given cache slot, wherein using the given cache slot includes identifying a memory address that is associated with the cache slot and executing at least one direct memory access (DMA) command based on the memory address,
• wherein the cache metadata table includes a global memory cache table for a storage system of which the computing device is part, and at least some of the plurality of cache slots are resident in random access memory modules of other computing devices that are part of the storage system,
• wherein identified memory address is a global memory address belonging to a memory namespace that encompasses multiple computing devices in the storage system,
• wherein allocating the given cache slot includes obtaining an identifier of a host device that is associated with the I/O request, and retrieving a location-based policy that corresponds to the host device, and
• wherein the given cache slot is allocated based on both the location-based policy and the respective location identifier of the given cache slot.

A non-transitory computer-readable medium storing one or more processor-executable instructions, which, when executed by at least one processor of a computing device, causes the computing device to perform the operations of:

• generating or updating a cache metadata table that identifies a plurality of cache slots, for each of the plurality of cache slots, the cache metadata table including a different respective location identifier that indicates a location for that cache slot;
• receiving an I/O request that is associated with a logical block address;
• allocating a given one of the plurality of cache slots to the logical block address based on the respective location identifier that corresponds to the given cache slot;
• and
• executing the I/O request by using the given cache slot, wherein using the given cache slot includes identifying a memory address that is associated with the cache slot and executing at least one direct memory access (DMA) command based on the memory address,
• wherein the cache metadata table includes a global memory cache table for a storage system of which the computing device is part, and at least some of the plurality of cache slots are resident in random access memory modules of other computing devices that are part of the storage system,
• wherein identified memory address is a global memory address belonging to a memory namespace that encompasses multiple computing devices in the storage system,
• wherein allocating the given cache slot includes obtaining an identifier of a host device that is associated with the I/O request, and retrieving a location-based policy that corresponds to the host device, and
• wherein the given cache slot is allocated based on both the location-based policy and the respective location identifier of the given cache slot.