US 12,189,487 B2
Optimizing deduplication hit-rate in a remote copy environment
Imran Imtiaz, Manchester (GB); Anuj Chandra, Pune (IN); and Miles Mulholland, Eastleigh (GB)
Assigned to International Business Machines Corporation, Armonk, NY (US)
Filed by INTERNATIONAL BUSINESS MACHINES CORPORATION, Armonk, NY (US)
Filed on Mar. 23, 2023, as Appl. No. 18/188,528.
Claims priority of application No. 2301454 (GB), filed on Feb. 1, 2023.
Prior Publication US 2024/0256390 A1, Aug. 1, 2024
Int. Cl. G06F 11/14 (2006.01); G06F 21/60 (2013.01)
CPC G06F 11/1453 (2013.01) [G06F 21/602 (2013.01); G06F 2201/84 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A computer implemented method for managing a storage system, the storage system comprising a primary system and a backup system, wherein the backup system is in a copy relationship with the primary system, the method comprising:
in response to a write input/output (I/O) operation, the write I/O operation comprising a deduplication and writing of first data:
at the primary system:
calculating a first cryptographic value for the first data;
scanning a first directory to identify an entry corresponding to the first cryptographic value to determine a first set of addresses associated with the deduplication;
transmitting the first set of addresses to the backup system; and
updating the first directory with a first entry for the deduplication, the first entry comprising a pointer to the first set of addresses;
at the backup system:
updating a second directory with a second entry for the deduplication, the second entry comprising a pointer to a second set of addresses corresponding to the first set of addresses;
reading specified ranges of synced referred copies; and
performing the deduplication.