Data storage device and method for storing selected data in relatively-lower data retention pages of a quad-level cell memory

1. A data storage device comprising:

a quad level cell (QLC) memory comprising a lower page (LP), a middle page (MP), an upper page (UP), and a top page (TP); and

one or more processors, individually or in combination, configured to:

determine data reliability of each of the pages;

write data for an internal data storage device operation in a first set of pages whose data retention is below a threshold; and

write host data in a second set of pages whose data retention is above the threshold.

2. The data storage device of claim 1 , wherein the one or more processors, individually or in combination, are further configured to:

write dummy data in the first set of pages to provide wider voltage threshold windows for the second set of pages.

3. The data storage device of claim 1 , wherein the internal data storage device operation comprises a static relocation.

4. The data storage device of claim 1 , wherein the internal data storage device operation comprises a folding operation.

5. The data storage device of claim 1 , wherein the internal data storage device operation comprises a generating a secondary copy of data.

6. The data storage device of claim 1 , wherein the data comprises firmware control data.

7. The data storage device of claim 1 , wherein the data comprises flash translation layer relocation data.

8. The data storage device of claim 1 , wherein the data comprises single-level cell (SLC) folding data.

9. The data storage device of claim 1 , wherein the quad-level cell memory comprises a three-dimensional memory.

10. In a data storage device, a method comprising:

determining if an entry in a priority queue has been halted due to ongoing data operations, wherein the entry is for a priority internal data storage device operation; and

in response to determining that the entry has been halted:

writing data for the priority internal data storage device operation in page(s) of a quad level cell (QLC) memory whose data retention is above a threshold; and

writing host data in other page(s) of the QLC.

11. The method of claim 10 , wherein the data for the priority internal data storage device operation and the host data are written in parallel.

12. The method of claim 10 , wherein the priority internal data storage device operation comprises a static relocation.

13. The method of claim 10 , wherein the priority internal data storage device operation comprises a folding operation.

14. The method of claim 10 , wherein the priority internal data storage device operation comprises generating a secondary copy of data.

15. The method of claim 10 , wherein the data comprises firmware control data.

16. The method of claim 10 , wherein the data comprises flash translation layer relocation data.

17. The method of claim 10 , wherein the data comprises single-level cell (SLC) folding data.

18. The method of claim 10 , further comprising selecting a block from a block list and allocating the block to the priority internal data storage device operation.

19. The method of claim 10 , wherein the plurality of pages comprises of a lower page (LP), a middle page (MP), an upper page (UP), and a top page (TP).

20. A data storage device comprising:

a memory comprising a multi-level cell memory comprising a plurality of pages;

means for determining data reliability of each of the pages;

means for writing data for an internal data storage device operation in pages whose data retention is below a threshold; and

means for writing host data in pages whose data retention is above the threshold.