Patent ID: 7827353

Claim:
A method for managing a data storage system, comprising: configuring a first cache to perform at least one of the operations of retrieving data from and storing data at a first range of logical addresses (LAs) in a storage device; configuring a second cache to perform at least one of the operations of retrieving data from and storing data at a second range of LAs and redundantly storing the data in the first range of LAs; configuring the first cache to redundantly store the data in the second range of LAs; configuring a plurality of caches to perform at least one of the operations of retrieving data from and storing data at a remaining range of LAs in the storage device and redundantly storing the data in the remaining range of LAs among the plurality of caches; mapping the first range of LAs, the second range of LAs, and the remaining range of LAs in a first map; detecting that the second cache is inoperable; reconfiguring the plurality of caches to perform the at least one of the operations of retrieving data from and storing data at the second range of LAs in response to the inoperability while continuing to perform at least one of the operations of retrieving data from and storing data at the remaining range of LAs; reconfiguring the plurality of caches to redundantly store the data in the first range of LAs in response to the inoperability while continuing to perform at least one of the operations of retrieving data from and storing data at the remaining range of LAs; mapping the second range of LAs and the redundantly stored data in the first range of LAs in a second map in response to the inoperability; utilizing the first map for requests that are directed to the first range of LAs and the remaining range of LAs in response to the inoperability; and utilizing the second map for future requests that are directed to the second range of LAs and to the redundantly stored data in the first range of LAs in response to the inoperability.