US 12,135,616 B1
Preserving storage efficiency during restoration of data from the cloud to a data storage system
Sumith Makam, Bangalore (IN); Roopesh Chuggani, Bengaluru (IN); Dnyaneshwar Pawar, Karnataka (IN); and Abhisar, Uttar Pradesh (IN)
Assigned to NetApp, Inc., San Jose, CA (US)
Filed by NetApp, Inc., San Jose, CA (US)
Filed on Apr. 21, 2023, as Appl. No. 18/304,583.
Int. Cl. G06F 11/14 (2006.01)
CPC G06F 11/1451 (2013.01) 20 Claims
OG exemplary drawing
 
1. A method of restoring data from an object store of a cloud to a volume of a data storage system, the method comprising:
maintaining, by the data storage system, a cloud block map (CBMAP) having entries that each map a cloud block number (CBN) of a plurality of CBNs to a corresponding block number of the volume, wherein a portion of the data associated with a given CBN of the plurality of CBNs was previously retrieved from the object store and stored within a given file data block of the volume, and wherein the given file data block is identified by the corresponding block number; and
preserving storage efficiency by the data storage system by:
prior to issuing a request for a particular portion of the data associated with a particular CBN from the object store, determining the particular CBN is present within an entry of the CBMAP that is valid; and
responsive to the determination, avoiding storing a duplicate file data block on the volume containing the particular portion of the data by instead storing a reference to the given file data block identified by the block number corresponding to the particular CBN.