Distributed multi-level caching for storage appliances

A computerized method that accesses an object stored in a cache of a distributed storage system, the method comprising:

• determining if the object is in the cache that stores a plurality of objects, wherein the distributed storage system includes the cache and a distributed object layer for persistently storing the plurality of objects in each of the plurality of storage controller servers of the distributed storage system, the cache is a multi-layer cache and further includes a de-duplicated layer 1 and 2 cache, a granularity of allocation for the layer 1 and 2 caches is different, and writes to the layer 2 cache are done at a segment granularity and reads from the layer 2 cache are done at the object granularity;
• if the object is in the cache, accessing the object from the cache;
• and
• if the object is not in the cache, accessing the object from the distributed object layer.

A distributed storage system to access an object in a cache of a distributed storage system, the distributed storage system comprising:

• an interconnection network;
• and
• a plurality of storage controllers, interconnected by the interconnection network, wherein each of the plurality of storage controllers includes,
• a distributed object layer that persistently stores a plurality of objects, and
• a distributed object caching layer, coupled to the distributed object layer,
• that accesses the object in the distributed storage system, the distributed object caching layer including,
• the cache that is a multi-layer cache and further includes a de-duplicated layer 1 and 2 cache, a granularity of allocation for the layer 1 and 2 caches is different, and writes to the layer 2 cache are done at a segment granularity and reads from the layer 2 cache are done at the object granularity;
• an access module, comprising a set of instructions, coupled to the cache, that determines if the object is in the cache, if the object is in the cache, the access module accesses the object from the cache, and if the object is not in the cache, the access module accesses the object from the distributed object layer.