Patent ID: 8898373
Filing Date: 2014-11-25
Classification: G06F

Abstract:
1. A method of performing wear leveling operations in a non-volatile data storage subsystem that comprises blocks of memory, the method comprising: receiving a command that specifies an erase operation on a superblock of a plurality of superblocks in the storage subsystem, said superblock comprising a plurality of blocks, each block residing in one of a plurality of dies in the storage subsystem, wherein each of the dies is associated with an individual wear leveling threshold that is based on (1) a position of the die within the plurality of dies and (2) an interval threshold denoting a minimum frequency at which a wear leveling operation is to be performed on a block; incrementing an erase counter associated with each block in said superblock to reflect said erase operation on the superblock; and using said erase counters to control a timing with which wear leveling operations are performed on specific blocks in the superblock, the timing being determined by comparing at least one of said erase counters to at least one of the individual wear leveling thresholds associated with the dies to determine whether an individual wear leveling threshold has been reached.