Storage Controller Differential Compression Versioning

The patent segments the data update process into two independent parts: (1) writing new data to a new page, and (2) independently erasing the old page when no longer needed. This segmentation allows the system to avoid the traditional sequential process where write operations must wait for garbage collection to complete, thereby reducing latency while maintaining efficient flash memory management.

The patent performs the write operation to a new page immediately without waiting for the old page to be erased. The erasure of the old page is deferred to a preliminary or background action that can be performed when the storage device has available capacity, thus eliminating the latency penalty of synchronous garbage collection while preserving data integrity.

The patent creates a new copy of the data in a new page rather than modifying the existing data in place. This copying approach allows the original data to remain undisturbed while the new copy is written independently, eliminating the need to read and rewrite overlapping tracks that would be required with shingled magnetic recording, thus reducing latency while achieving the same storage density benefits.

The patent introduces a new page as an intermediary structure that holds the updated data. Instead of directly modifying existing data in overlapping tracks, the system uses this intermediate page to store the new data version, which can then be independently managed and erased without affecting other data, thereby decoupling the write operation from the constraints of shingled magnetic recording.