Solid state drive using two-level indirection architecture
Aspects of the present disclosure provide systems and methods for operating a solid state drive (SSD) using two-level indirection architecture. The SSD receives a command to perform a data operation in a NAND array and a logical address for the data operation. The SSD then converts the logical address to a physical address using a two-stage logical-to-physical (L2P) mapping table that includes a first stage stored in a byte-rewritable memory and a second stage stored in a block-erasable non-volatile memory (NVM). The SSD performs the data operation in the NAND array based on the physical address. The byte-rewritable memory may any byte-rewritable persistent memory. The block-erasable low latency NVM may be a flash memory that has lower latency than NAND array.
1. A method of operating a solid state drive (SSD), comprising:
receiving a command to perform a data operation in a NAND array and a logical address for the data operation;
converting the logical address to a physical address using a two-stage logical-to-physical (L2P) mapping table comprising a partition table stored in a byte-rewritable non-volatile memory and a plurality of L2P table partitions stored in a block-erasable non-volatile memory (NVM) that has faster access than the NAND array; and
performing the data operation in the NAND array based on the physical address.
2. The method of claim 1 ,
wherein the converting comprises:
determining, using the partition table, a location in the block-erasable NVM storing the L2P table partition corresponding to the logical address for the data operation; and
determining, using the L2P table partition, the physical address for performing the data operation in the NAND array.
3. The method of claim 2 , wherein the performing the data operation comprises:
programming second data, received as part of the command, to the NAND array to replace first data stored in the NAND array; and
updating the partition table and the L2P table partition to map the logical address to a physical address of the second data.
4. The method of claim 3 , wherein the updating comprises:
updating an L2P entry in the L2P table partition to store the physical address of the second data; and
updating an entry in the partition table to store a new location of the updated L2P table partition.
5. The method of claim 1 , wherein the command comprises, at least one of:
a program command for writing data to a page of the NAND array; or
a read command for reading data from a page of the NAND array.
6. The method of claim 1 , wherein:
the partition table comprises a plurality of partition indexes,
wherein each partition index indicates a location of a corresponding one of the L2P table partitions in the block-erasable NVM.
7. A solid state device (SSD) comprising:
a communication interface configured to communicate with a host;
a NAND array;
a byte-rewritable non-volatile memory;
a block-erasable non-volatile memory (NVM) that has faster access than the NAND array; and
a controller operatively coupled with the communication interface and the NAND array, wherein the controller is configured to:
receive, from the host, a command to perform a data operation in the NAND array and a logical address for the data operation;
convert the logical address to a physical address using a two-stage logical-to-physical (L2P) mapping table comprising a partition table stored in the byte-rewritable non-volatile memory and a plurality of L2P table partitions stored in the block-erasable NVM; and
perform the data operation in the NAND array based on the physical address.
8. The SSD of claim 7 ,
wherein the controller is further configured to:
determine, using the partition table, a location in the block-erasable NVM storing the L2P table partition corresponding to the logical address for the data operation; and
determine, using the L2P table partition, the physical address for performing the data operation in the NAND array.
9. The SSD of claim 8 , wherein the controller is further configured to:
program second data, received as part of the command, to the NAND array to replace first data stored in the NAND array; and
update the partition table and the L2P table partition to map the logical address to a physical address of the second data.
10. The SSD of claim 9 , wherein the controller is further configured to:
update an L2P entry in the L2P table partition to store the physical address of the second data; and
update an entry in the partition table to store a new location of the updated L2P table partition.
11. The SSD of claim 7 , wherein the command comprises, at least one of:
a program command for writing data to a page of the NAND array; or
a read command for reading data from a page of the NAND array.
12. The SSD of claim 7 , wherein:
the partition table comprises a plurality of partition indexes,
and wherein each partition index indicates a location of a corresponding one of the L2P table partitions in the block-erasable NVM.
13. A solid state drive (SSD), comprising:
means for receiving a command to perform a data operation in a NAND array and a logical address for the data operation;
means for converting the logical address to a physical address using a two-stage logical-to-physical (L2P) mapping table comprising a partition table stored in a byte-rewritable non-volatile memory and a plurality of L2P table partitions stored in a block-erasable non-volatile memory (NVM) that has faster access than the NAND array; and
means for performing the data operation in the NAND array based on the physical address.
14. The SSD of claim 13 ,
wherein the means for converting is configured to:
determine, using the partition table a location in the block-erasable NVM storing the L2P table partition corresponding to the logical address for the data operation; and
determine, using the L2P table partition, the physical address for performing the data operation in the NAND array.
15. The SSD of claim 14 , wherein the means for performing the data operation is configured to:
program second data to the NAND array to replace first data stored in the NAND array; and
update the partition table and the L2P table partition to map the logical address to a physical address of the second data.
16. The SSD of claim 15 , wherein the means for performing the data operation is further configured to:
update an L2P entry in the L2P table partition to store the physical address of the second data; and
update an entry in the partition table to store a new location of the updated L2P table partition.
17. The SSD of claim 13 , wherein the command comprises, at least one of:
a program command for writing data to a page of the NAND array; or
a read command for reading data from a page of the NAND array.
18. The SSD of claim 13 , wherein:
the partition table comprises a plurality of partition indexes,
wherein each partition index indicates a location of a corresponding one of the L2P table partitions in the block-erasable NVM.
19. A solid state drive (SSD) comprising:
a NAND array;
a byte-rewritable non-volatile memory;
a block-erasable non-volatile memory (NVM) that has faster access than the NAND array; and
a controller operatively coupled with the NAND array, the byte-rewritable non-volatile memory, and the block-erasable NVM,
wherein the controller is configured to:
store first data in the NAND array using a two-stage logical-to-physical (L2P) mapping table comprising a partition table and a plurality of table partitions;
store the partition table in the byte-rewritable non-volatile memory, the partition table comprising a plurality of indexes corresponding to the plurality of table partitions; and
store the plurality of table partitions in the block-erasable NVM, each table partition comprising a plurality of physical addresses of the NAND array mapped to logical addresses of the first data.
20. The SSD of claim 19 , wherein the controller is further configured to:
store second data in the NAND array;
update one or more of the plurality of table partitions to store one or more physical addresses of the NAND array for storing the second data; and
update one or more indexes of the partition table corresponding to the updated one or more table partitions.
21. The SSD of claim 19 , wherein the controller is further configured to:
cache one or more of the table partitions in the byte-rewritable non-volatile memory.