Western Digital Technologies, Inc.

Nicholas Thomas

Karin Inbar

Eran Erez

Raghavendra Gopalakrishnan

Matthew Davidson

In one embodiment, there is a method for managing data in a storage device comprising a non-volatile memory having a plurality of jumbo blocks, each jumbo block having a separate and distinct physical block address. The method comprises performing a folding operation data associated with a first virtual address from a plurality of Single Level Cell (SLC) jumbo blocks of the non-volatile memory to one Multilevel Cell (MLC) jumbo block of the non-volatile memory, receiving a read request to read data associated with a first logical block address, identifying that the first virtual address is associated with the first logical block address, determining whether a jumbo block associated with the first logical block address meets pre-SLC-overwrite criteria. In response to a determination that the jumbo block associated with the first logical block address meets pre-SLC-overwrite criteria, reading data from the SLC jumbo block associated with the first virtual address. In response to a determination that the jumbo block associated with the first logical block address does not meet pre-SLC-overwrite criteria, reading data from the MLC jumbo block associated with the first virtual address.

Smart mapping table update post background operations

A method that uses a reduced logical and physical address field size for storing data having steps of receiving a set of data to write to a solid state drive, determining a logical address to the set of data, setting a logical offset of the set of data to be equal to a physical block offset modulo of the data and writing the set of data to the solid state drive in locations on solid state drive that accept a size of the address of the set of data is disclosed.

Logical and physical address field size reduction by alignment-constrained writing technique

The disclosure relates in some aspects to managing multi-tier memory, such as multi-tier NVM. Data that is originally written to a first tier (e.g., a fast tier) may be subsequently copied to a second tier (e.g., a slow tier). The data is temporarily left in the first tier until the space is needed for a subsequent write operation. Thus, for a period of time, a read operation is able to read the data from the first tier (e.g., the fast tier) instead of the second tier (e.g., the slow tier), thereby improving read performance. The disclosure relates in some aspects to a memory mapping scheme that enables a read operation to readily determine that data remains in the first tier and locate the data in that tier. Moreover, the scheme enables efficient reconfiguration of the mapping when the data in the first tier is erased.

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Edinburgh, United Kingdom

Nicholas Thomas