Patent ID: 8549226

Claim:
A method of providing an auxiliary caching scheme at a storage area network level, the method comprising: determining that a number of accesses to a portion of data in a storage device reaches a threshold that is greater than one access, the storage device including a primary cache to cache the data according to a first caching scheme; storing a copy of said portion of data in an auxiliary cache in response to the number of accesses to said portion of data reaching said threshold, wherein said auxiliary cache is at said storage area network (SAN) level and is external of the storage device, and wherein said auxiliary cache employs a second caching scheme that is different from the first caching scheme; for subsequent accesses to said portion of data, accessing said copy of said portion of data instead of accessing said portion of data; and dynamically vary said threshold based on a number of cache hits to copies of portions of data in said auxiliary cache, and a number of migrations of portions of data to said auxiliary cache.