Hybrid logical to physical mapping for zns based ssds

Abstract

Aspects of a storage device are provided that handle host commands associated with active and inactive zones using a hybrid L2P mapping system. The storage device includes a NVM, a controller, a first volatile memory and a second volatile memory. The controller allocates, as a superblock, one or more physical blocks respectively in one or more memory dies of the NVM, receives write commands including logical addresses associated with active zones, and stores in an L2P mapping table L2P address mappings of these logical addresses to physical addresses associated with either volatile memory or the superblock. The controller refrains from storing L2P address mappings for inactive zones, instead storing in a superblock mapping table a mapping of superblocks to inactive zones in response to respective zone finish commands. As a result, L2P mapping table sizes are reduced, zone read, reset, and TTR performance are increased, and reduced WAF is achieved.