Western Digital Technologies, Inc.

Eugene Lisitsyn

Jerry Lo

Yun-Tzuo Lai

Subhash Balakrishna Pillai

Kai-Lung Cheng

The subject technology provides for managing a data storage system. A host write command to write host data associated with a logical address to a non-volatile memory is received. A first physical address in the non-volatile memory mapped to the logical address in an address mapping table is determined. An indicator that the first physical address is bad checked. If the first physical address is indicated as bad, a valid count associated with a first set of physical addresses at a current value is maintained. The first set of physical addresses comprises the first physical address. If the first physical address is not indicated as bad, the first physical address is marked as invalid. The valid count associated with the first set of physical addresses is decremented.

Managing data for a data storage system

Host data segments are received and stored in a cached data unit corresponding to a previously stored data unit currently stored in non-volatile memory. Metadata is created that identifies unmodified previously stored segments of host data in the previously stored data unit that correspond to the received host data segments, the metadata including an update flag indicating that the previously stored data unit requires updating. In response to detecting the unexpected interruption of power, the cached data unit and the metadata is written to an area of the non-volatile memory array that is different than where the previously stored data unit is currently stored. Upon resuming operation following the unexpected interruption of power, the cached data unit is identified based on the update flag, as having been saved in response to the power shutdown without the previously stored data unit being updated in the non-volatile memory array, and then reloaded into the memory cache.

Growing community of inventors

Anaheim, CA, United States of America

Eugene Lisitsyn