Memory system and operating method to perform read reclaim operation based on read count

Patent metadata

Field	Value
Publication number	US-10521341-B2
Application number	US-201816038635-A
Country	US
Kind code	B2
Filing date	Jul 18, 2018
Priority date	Jan 18, 2018
Publication date	Dec 31, 2019
Grant date	Dec 31, 2019

Abstract

A memory system includes a memory device including a plurality of memory blocks, and a controller suitable for measuring read counts of the memory blocks, calculating a global read count based on the measured read counts, and controlling the memory device to perform a read reclaim operation on a victim block when the global read count is equal to or higher than a threshold value.

First claim

What is claimed is:

1. A memory system, comprising:
a memory device including a plurality of memory blocks; and
a controller suitable for measuring read counts of the memory blocks at a timing, calculating a global read count based on the measured read counts, and controlling the memory device to perform a read reclaim operation on a victim block when the global read count is equal to or higher than a threshold value,
wherein the timing is adjusted based on an increase rate of the global read count.

2. The memory system of claim 1 , wherein the controller calculates the global read count by calculating a total sum of the measured read counts of the memory blocks.

3. The memory system of claim 1 ,
wherein the controller measures the read counts of the memory blocks at the timing determined based on a fixed host read amount, and
wherein the controller decreases the fixed host read amount when the increase rate of the global read count is higher than a reference increase rate.

4. The memory system of claim 3 , wherein the controller calculates the increase rate of the global read count based on a ratio of a host read amount and the global read count.

5. The memory system of claim 1 , wherein the controller detects the victim block based on the measured read counts.

6. The memory system of claim 5 , wherein the victim block is a block whose read count is equal to or higher than a read reclaim reference.

7. The memory system of claim 1 , wherein the controller stores the read count of each of the memory blocks and the global read count in any one of the memory blocks.

8. The memory system of claim 1 , wherein the controller determines at least one attribute of a read command of a host and applies a fixed host read amount based on the at least one attribute.

9. The memory system of claim 8 , wherein the controller increases the fixed host read amount when the read command is a sequential read command.

10. The memory system of claim 8 , wherein the controller decreases the fixed host read amount when the read command is a random read command.

11. An operating method of a memory system, comprising:
measuring read counts of a plurality of memory blocks at a timing;
calculating a global read count based on the measured read counts; and
performing a read reclaim operation on a victim block when the global read count is equal to or higher than a threshold value,
wherein the timing is adjusted based on an increase rate of the global read count.

12. The operating method of claim 11 , wherein the global read count is calculated by calculating a total sum of the measured read counts of the memory blocks.

13. The operating method of claim 11 ,
wherein the measuring of the read counts of a plurality of memory blocks is performed at the timing determined based on a fixed host read amount, and
wherein the fixed host read amount is decreased when the increase rate of the global read count is higher than a reference increase rate.

14. The operating method of claim 13 , wherein the increase rate of the global read count is calculated based on a ratio of a host read amount and the global read count.

15. The operating method of claim 11 , further comprising:
detecting the victim block based on the measured read counts.

16. The operating method of claim 15 , wherein the victim block is a block whose read count is equal to or higher than a read reclaim reference.

17. The operating method of claim 11 , further comprising:
storing the read count of each of the memory blocks and the global read count in any one of the memory blocks.

18. The operating method of claim 11 , further comprising:
determining at least one attribute of a read command of a host and applying a fixed host read amount based on the at least one attribute.

19. The operating method of claim 18 , wherein the fixed host read amount is increased when the read command is a sequential read command.

20. The operating method of claim 18 , wherein the fixed host read amount is decreased when the read command is a random read command.

Assignees

• Sk Hynix Inc

Inventors

• Lee Jong-Min

Classifications

• G06F3/0652

  Erasing, e.g. deleting, data cleaning, moving of data to a wastebasket · CPC title

• G06F3/0611

  in relation to response time · CPC title

• G06F3/064

  Management of blocks · CPC title

• G06F2212/7205

  Cleaning, compaction, garbage collection, erase control · CPC title

• G06F2212/7203

  Temporary buffering, e.g. using volatile buffer or dedicated buffer blocks · CPC title