Logical band-based key-value storage structure

1. A computing system comprising:

a processor communicatively coupled to an indexing structure and a datastore log separate from the indexing structure, wherein the indexing structure is to store key data corresponding to a key of a key-value pair and an address for the key-value pair, and wherein the datastore log is to store the key-value pair at the address in a logical band of a plurality of independent logical bands;

one or more memory devices coupled to the processor, the one or more memory devices including instructions, which when executed by the processor, cause the computing system to:

execute an operation involving the key-value pair;

populate at least one logical band of the plurality of independent logical bands with data for a logical band footer so that the logical band footer is to include one or more of a status token or an error code;

populate the at least one logical band with data for one or more of a logical band header, a logical band entry or a logical band journal;

populate the logical band header with a sequence number;

populate the logical band entry with data for a logical band entry header; and

populate the logical band journal with a hash table entry when the indexing structure is a hash table.

2. The computing system of claim 1 , wherein the instructions, when executed, cause the computing system to map the datastore log to one or more of a file system, logical block addressing, or storage device physical bands to divide the datastore log into the plurality of independent logical bands.

3. The computing system of claim 1 , wherein the logical band entry header is to include a type field, a key length field, a value length field, the key-value pair, and an error code for the key-value pair.

4. The computing system of claim 1 , wherein the instructions, when executed, cause the computing system to insert a current address for the key-value pair at the indexing structure.

5. The computing system of claim 1 , wherein the instructions, when executed, cause the computing system to:

update an invalidity datastore with an invalidity count and with an erase count when the erase count is to be tracked;

update a logical band linked list with a clean logical band or a closed logical band and obtain a next clean logical band from the logical band linked list when needed; and

update statistic information in a statistics datastore for the computing system.

6. The computing system of claim 1 , wherein the instructions, when executed, cause the computing system to:

select a target logical band based on an invalidity count and an erase count, and relocate all valid key-value pairs from the target logical band to a current logical band and erase the target logical band; and

recover one or more of a last opened logical band, a most recent indexing structure, or a most recent system level datastore.

7. A storage system comprising:

a memory that includes an indexing structure and a datastore log separate from the indexing structure, wherein the indexing structure is to store key data corresponding to a key of a key-value pair and an address for the key-value pair, wherein the datastore log is to store the key-value pair at the address in a logical band of a plurality of independent logical bands; and

a memory controller communicatively coupled to the memory, and wherein the memory controller is configured in circuitry to:

execute an operation involving the key-value pair;

populate a footer of at least one logical band of the plurality of independent logical bands with one or more of a status token or an error code;

populate a logical band header with a sequence number;

populate a logical band entry with data for a logical band entry header; and

populate a logical band journal with a hash table entry when the indexing structure is a hash table.

8. The storage system of claim 7 , wherein the logical band entry header is to include a type field, a key length field, a value length field, the key-value pair, and an error code for the key-value pair.

9. The storage system of claim 7 , wherein the memory controller is to insert a current address for the key-value pair at the indexing structure.

10. The storage system of claim 7 , wherein the memory controller is to:

update an invalidity datastore with an invalidity count and with an erase count when the erase count is to be tracked;

update a logical band linked list with a clean logical band or a closed logical band and obtain a next clean logical band from the logical band linked list when needed; and

update statistic information in a statistics datastore for a storage system.

11. The storage system of claim 7 , wherein the memory controller is to:

select a target logical band based on an invalidity count and an erase count, and relocate all valid key-value pairs from the target logical band to a current logical band and erase the target logical band; and

recover one or more of a last opened logical band, a most recent indexing structure, or a most recent system level datastore.

12. At least one non-transitory computer readable storage medium comprising a set of instructions, which when executed by a processor, cause the processor to:

store in an indexing structure key data corresponding to a key of a key-value pair and an address for the key-value pair;

store in a datastore log separate from the indexing structure the key-value pair at the address in a logical band of a plurality of independent logical bands;

execute an operation involving the key-value pair;

populate a footer of at least one logical band of the plurality of independent logical bands with one or more of a status token or an error code;

populate a logical band header with a sequence number;

populate a logical band entry with data for a logical band entry header; and

populate a logical band journal with a hash table entry when the indexing structure is a hash table.

13. The at least one non-transitory computer readable storage medium of claim 12 , wherein the logical band entry header is to include a type field, a key length field, a value length field, the key-value pair, and an error code for the key-value pair.

14. The at least one non-transitory computer readable storage medium of claim 12 , wherein the instructions, when executed, cause the processor to insert a current address for the key-value pair at the indexing structure.

15. The at least one non-transitory computer readable storage medium of claim 12 , wherein the instructions, when executed, cause the processor to:

update an invalidity datastore with an invalidity count and with an erase count when the erase count is to be tracked;

update a logical band linked list with a clean logical band or a closed logical band and obtain a next clean logical band from the logical band linked list when needed; and

update statistic information in a statistics datastore for a storage system.

16. The at least one non-transitory computer readable storage medium of claim 12 , wherein the instructions, when executed, cause the processor to:

select a target logical band based on an invalidity count and an erase count, and relocate all valid key-value pairs from the target logical band to a current logical band and erase the target logical band; and

recover one or more of a last opened logical band, a most recent indexing structure, or a most recent system level datastore.

17. A method comprising:

storing in an indexing structure key data corresponding to a key of a key-value pair and an address for the key-value pair;

storing in a datastore log separate from the indexing structure the key-value pair at the address in a logical band of a plurality of independent logical bands;

executing an operation involving the key-value pair;

populating a footer of at least one logical band of the plurality of independent logical bands with one or more of a status token or an error code;

populating a logical band header with a sequence number;

populating a logical band entry with data for a logical band entry header; and

populating a logical band journal with a hash table entry when the indexing structure is a hash table.

18. The method of claim 17 , wherein the logical band entry header is to include a type field, a key length field, a value length field, the key-value pair, and an error code for the key-value pair.

19. The method of claim 17 , further including inserting a current address for the key-value pair at the indexing structure.

20. The method of claim 17 , further including:

selecting a target logical band based on an invalidity count and an erase count, and relocating all valid key-value pairs from the target logical band to a current logical band and erase the target logical band; and

recovering one or more of a last opened logical band, a most recent indexing structure, or a most recent system level datastore.