Storage delta compression
The present disclosure generally relates to more efficient use of a delta buffer. To utilize the delta buffer, an efficiency can be gained by utilizing absolute delta entries and relative delta entries. The absolute delta entry will include the type of delta entry, the L2P table index, the L2P table offset, and the PBA. The relative delta entry will include the type of delta entry, the L2P table offset, and the PBA offset. The relative delta entry will utilize about half of the storage space of the absolute delta entry. The relative delta entry can be used after an absolute delta entry so long as the relative delta entry is for data stored in the same block as the previous delta entry. If data is stored in a different block, then the delta entry will be an absolute delta entry.
1. A data storage device, comprising:
one or more memory devices; and
a controller coupled to the one or more memory devices, wherein the controller is configured to:
determine that a plurality of entries for a delta buffer logical to physical (L2P) table correspond to a same data block;
create an absolute delta L2P entry, wherein the absolute delta L2P entry comprises a first number of bits;
store the absolute delta L2P entry in the delta buffer L2P table;
create a relative delta L2P entry, wherein the relative delta L2P entry comprises a second number of bits and wherein the first number of bits is greater than the second number of bits; and
store the relative delta L2P entry in the delta buffer L2P table.
2. The data storage device of claim 1 , wherein the absolute delta L2P entry comprises a type of entry, a L2P table part index, a first offset in the L2P table, and a physical block address (PBA).
3. The data storage device of claim 2 , wherein the relative delta L2P entry comprises a type of entry, a second offset in the L2P table, and a PBA offset.
4. The data storage device of claim 3 , wherein the first offset in the L2P table and the second offset in the L2P table comprise an equal number of bits, and wherein the PBA comprises a greater number of bits than the PBA offset.
5. The data storage device of claim 1 , wherein the first number of bits is between about 55 and 64 bits.
6. The data storage device of claim 5 , wherein the second number of bits is between about 28 and about 32 bits.
7. The data storage device of claim 1 , wherein the controller is further configured to:
create a second relative delta L2P entry, wherein the second relative delta L2P entry comprises a third number of bits; and
store the second relative delta L2P entry in the delta buffer L2P table.
8. The data storage device of claim 7 , wherein the third number of bits is equal to the second number of bits.