Distributed multi-level caching for storage appliances

摘要

A distributed multi-layer cache in a distributed storage system is described, where the storage controller functions of the distributed storage system are separated from that of distributed storage system storage media. In an exemplary embodiment, a storage controller server determines if an object is in a cache that stores a plurality of objects. In addition, the distributed storage system includes the cache and a distributed object layer for persistently storing the plurality of objects. The cache further includes a de-duplicated cache layer. The storage controller server accesses the object from the cache if the object is in the cache and accesses the object from the distributed object layer if the object is not in the cache.

主权项

1. A non-transitory machine-readable medium having executable instructions to cause one or more processing units to perform a method to access 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.