Patent ID: 8819367

Claim:
A storage subsystem, comprising: a first memory, the first memory comprising at least one non-volatile memory device and arranged in one or more zones; a second memory different than the first memory; and a controller, configured to: maintain a current version of a logical-to-physical address mapping in the second memory that maps logical addresses to storage locations of the first memory; at a first point in time, store a copy of the logical-to-physical address mapping in the first memory; in response to requests from a host system and using the current version of the logical to physical address mapping, store user data in the zones of the first memory; accumulate, in the first memory, change data indicative of changes to the current logical-to-physical mapping relative to the stored copy of the logical-to-physical address mapping; and at a second point in time later than the first point in time, and upon accumulating a threshold amount of change data in the first memory, update the copy of the logical-to-physical address mapping stored in the first memory to reflect the accumulated change data.