Zoned namespace limitation mitigation using sub block mode

Abstract

Aspects of a storage device including a memory and a controller are provided which reduces or eliminates garbage collection in zoned namespace (ZNS) architectures by mapping zones to sub-blocks of blocks of the memory. Each zone includes a plurality of logical addresses. The controller determines a number of open zones, and maps the open zones to the sub-blocks in response to the number of open zones meeting a threshold. Thus, larger numbers of open blocks typically present in ZNS may be reduced, and increased block sizes due to scaling may be accommodated in ZNS. In some aspects, the controller receives a request from a host device to write data associated with the zones in sub-blocks, and maps each of the zones to at least one of the sub-blocks in response to the request. The request may indicate zones are partially unused. Thus, out of zone conditions may also be avoided.