Flush method for mapping table of SSD

Patent metadata

Field	Value
Publication number	US-11789864-B2
Application number	US-202217825985-A
Country	US
Kind code	B2
Filing date	May 26, 2022
Priority date	May 22, 2020
Publication date	Oct 17, 2023
Grant date	Oct 17, 2023

Abstract

A method of operating a Solid-State Drive (SSD) includes determining optimized thresholds of each corresponding segments according to their frequency of use, and executing a flush operation to write the one of the corresponding segments into a memory device according to the optimized thresholds of the corresponding segments.

First claim

What is claimed is:

1. A method of operating a Solid-State Drive (SSD), comprising:
determining first thresholds of each corresponding segments of a mapping table according to frequency of use of the segments, wherein the mapping table comprises Logical Block Addresses (LBAs), the LBAs are divided into multiple corresponding segments; and
executing a flush operation to write the one of the corresponding segments of the mapping table into a memory device according to the first thresholds of the corresponding segments of the mapping table,
wherein each first threshold of corresponding segment of the mapping table is determined by an equation of:

O
=

B

(

1
-

C
T

)

=

B
×
T

(

T
-
C

)

where O is defined as one of the first thresholds, B is defined as a base threshold corresponding to the segments of the mapping table, C is defined as one of count values of the corresponding segments of the mapping table, and T is defined as a number of total written LBAs.

2. The method of claim 1 ,
wherein the count value corresponds to the number of the corresponding LBAs being written into the mapping table.

3. The method of claim 1 , wherein executing the flush operation to write the one of the corresponding segments of the mapping table into the memory device according to the first thresholds of the corresponding segments of the mapping table comprises:
executing the flush operation to write the one of the corresponding segments of the executing the flush operation to write the one of the corresponding segments of the mapping table into the memory device when a count value of the corresponding segments of the mapping table is greater than the first thresholds of the corresponding segments of the mapping table.

4. The method of claim 1 , further comprising:
recording each of the count values of the corresponding segment of the mapping table.

5. The method of claim 1 , further comprising:
recording the number of total written LBAs.

6. The method of claim 1 , further comprising:
generating a recording table configured to record each of the count values of the corresponding segments of the mapping table and the number of total written LBAs.

7. The method of claim 6 , further comprising:
in response to the number of total written LBAs reaches a predetermined threshold count, cleaning the recording table by resetting the count values, the number of total written LBAs, and the first thresholds to zero.

8. The method of claim 6 , further comprising:
acquiring the recording table from the memory device after the SSD is powered on.

9. A solid-state drive (SSD), comprising:
a memory device comprising a non-volatile memory configured to store a mapping table, wherein the mapping table comprises Logical Block Addresses (LBAs), the LBAs are divided into multiple corresponding segments; and
a memory controller configured to execute an instruction to perform a flush process, wherein the flush process comprises:
determining first thresholds of each of the corresponding segments of the mapping table according to frequency of use the segments; and
executing a flush operation to write the one of the corresponding segments of the mapping table into a memory device according to the first thresholds of the corresponding segments of the mapping table,
wherein each first threshold of corresponding segment of the mapping table is determined by an equation of:

O
=

B

(

1
-

C
T

)

=

B
×
T

(

T
-
C

)

where O is defined as one of the first thresholds, B is defined as a base threshold corresponding to the segments of the mapping table, C is defined as one of count values of the corresponding segments of the mapping table, and T is defined as a number of total written LBAs.

10. The SSD of claim 9 ,
wherein the count value corresponds to the number of the corresponding LBAs being written into the mapping table.

11. The SSD of claim 9 , wherein executing the flush operation to write the one of the corresponding segments of the mapping table into the memory device according to the first thresholds of the corresponding segments of the mapping table further comprises:
executing the flush operation to write the one of the corresponding segments of the executing the flush operation to write the one of the corresponding segments of the mapping table into the memory device when a count value of the corresponding segments of the mapping table is greater than the first thresholds of the corresponding segments of the mapping table.

12. The SSD of claim 9 , wherein the flush process further comprises:
recording each of the count values of the corresponding segment of the mapping table.

13. The SSD of claim 9 , wherein the flush process further comprises:
recording the number of total written LBAs.

14. The SSD of claim 9 , wherein the flush process further comprises:
generating a recording table configured to record each of the count values of the corresponding segments of the mapping table and the number of total written LBAs.

15. The SSD of claim 14 , wherein the flush process further comprises:
in response to the number of total written LBAs reaches a predetermined threshold count, cleaning the recording table by resetting the count values, the number of total written LBAs, and the first thresholds to zero.

16. The SSD of claim 14 , wherein the flush process further comprises:
acquiring the recording table from the memory device after the SSD is powered on.

17. A system comprising:
a host comprising a host memory and a host processor;
a memory device comprising a non-volatile memory configured to store a mapping table; and
a memory controller comprising a control circuit configured to execute an instruction from the host to perform a flush process, wherein the flush process comprises:
determining first thresholds of each corresponding segments of the mapping table according to frequency of use of the segments, wherein the mapping t

Assignees

• Yangtze Memory Tech Co Ltd

Inventors

• Zhang Lei
• Ding Keke
• Wang li wei

Classifications

• G06F12/0292 Primary

  using tables or multilevel address translation means (G06F12/023 takes precedence; address translation in virtual memory systems G06F12/10) · CPC title

• G06F9/30047

  Prefetch instructions; cache control instructions · CPC title

• G06F11/3037

  where the computing system component is a memory, e.g. virtual memory, cache (accessing, addressing or allocating within memory systems or architectures G06F12/00; checking stores for correct operation G11C29/00) · CPC title

• G06F12/0246 Primary

  in block erasable memory, e.g. flash memory · CPC title

• G06F2212/214

  Solid state disk · CPC title