Zoned namespace limitation mitigation using sub block mode
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.
1. A storage device, comprising:
a memory comprising a plurality of blocks, wherein each of the blocks includes a plurality of sub-blocks; and
a controller configured to map a zone to at least one of the sub-blocks, wherein the zone includes a plurality of logical addresses;
wherein the controller is further configured to determine a number of open zones, and to map the zone to the at least one of the sub-blocks in response to the number of open zones meeting a threshold.
2. The storage device of claim 1 , wherein each of the sub-blocks is independently programmable and erasable.
3. The storage device of claim 1 , wherein the controller is further configured to receive from a host an association of the zone with the logical addresses.
4. The storage device of claim 1 , wherein the zone is mapped to two of the sub-blocks, the two of the sub-blocks being from different blocks.
5. The storage device of claim 4 , wherein each of the different blocks includes another sub-block mapped to a different zone.
6. The storage device of claim 1 , wherein the zone is mapped to one of the sub-blocks in response to an indication from a host that the zone is partially unused, the one of the sub-blocks being in one of the blocks.
7. The storage device of claim 6 , wherein the one of the blocks includes another sub-block mapped to a different zone.
8. A storage device, comprising:
a memory comprising a plurality of blocks, wherein each of the blocks includes a plurality of sub-blocks; and
a controller configured to determine a number of open zones, and to map open zones to the sub-blocks in response to the number of open zones meeting a threshold.
9. The storage device of claim 8 , wherein each of the sub-blocks is independently readable and programmable.
10. The storage device of claim 8 , wherein the controller is further configured to receive from a host an association of each of the open zones with a plurality of logical addresses.
11. The storage device of claim 8 , wherein each of the open zones is mapped to two of the sub-blocks, the two of the sub-blocks being from different blocks.
12. The storage device of claim 8 , wherein each of the open zones is mapped to one of the sub-blocks in response to an indication from a host that the open zones will not be completely written.
13. A storage device, comprising:
a memory comprising a plurality of blocks, wherein each of the blocks includes a plurality of sub-blocks; and
a controller configured to receive a request to write data associated with zones in the sub-blocks, and to map each of the zones to at least one of the sub-blocks in response to the request;
wherein the controller is further configured to determine a number of the zones that are open, and to map the zones to the sub-blocks in response to the number of the zones that are open meeting a threshold.
14. The storage device of claim 13 , wherein each of the sub-blocks is independently readable and erasable.
15. The storage device of claim 13 , wherein the controller is further configured to receive from a host an association of each of the zones with a plurality of logical addresses.
16. The storage device of claim 13 , wherein each of the zones is mapped to two of the sub-blocks, the two of the sub-blocks being from different blocks.
17. The storage device of claim 13 , wherein the request includes an indication from a host that the zones are partially unused.
18. The storage device of claim 17 , wherein each of the zones is mapped to one of the sub-blocks in response to the indication.