System, method, and computer program product for analyzing monitor data information from a plurality of memory devices having finite endurance and/or retention

• US 8,316,173 B2
• Filed: 04/08/2009
• Issued: 11/20/2012
• Est. Priority Date: 04/08/2009
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Hetzler, Steven Robert, Kabelac, William John
• Primary Examiner(s): Auduong, Gene
• Application Number:
  US12/420,628
• Publication Number:
  US 20100262795A1
• Time in Patent Office: 1,322 Days
• Field of Search: 711/103, 711/156, 711/162, 711/E12.103, 714/2, 714/701, 714/702, 714/718, 714/719, 365/200, 365/201, 365/185.09, 365/185.11, 365/185.33
• US Class Current: 711/103
• CPC Class Codes: G06F 11/1068 in sector programmable memories, e.g. flash disk G06F11/1072 takes precedence
• CPC Class Codes: G11C 16/349 Arrangements for evaluating degradation, retention or wearout, e.g. by counting erase cycles
• CPC Class Codes: G11C 2029/0409 Online test
• CPC Class Codes: G11C 29/52 Protection of memory contents; Detection of errors in memory contents

Abstract

A method according to one embodiment includes gathering monitor data information from a plurality of memory devices having finite endurance and/or retention, the monitor data being data of known content stored in dedicated memory cells of known write cycle count; analyzing the monitor data information; and taking an action relating to at least one of the devices based on the analyzing. Additional systems, methods, and computer program products are also disclosed.

Claims

1. A method, comprising:

gathering information about monitor data from a plurality of memory devices having finite endurance and/or retention, the monitor data being;

(i) data of known content stored in dedicated memory cells of known write cycle count, (ii) not subject to wear leveling, and (iii) write protected for preventing the monitor data from being overwritten with user data;

wherein the information about the monitor data includes error rate information relating to the data age of the monitor data;

analyzing the information about the monitor data; and

taking an action relating to at least one of the devices based on the analyzing.

2. The method of claim 1, further comprising generating the monitor data.

3. The method of claim 1, wherein the information about the monitor data includes error rate information relating to the data age of the monitor data.

4. The method of claim 1, further comprising performing the gathering and analyzing steps at least twice, and generating a statistical trend based thereon.

5. The method of claim 1, further comprising performing the gathering and analyzing steps at least twice, and tracking a time-dependence of the monitor data.

6. The method of claim 1, wherein taking the action includes setting a behavioral target for at least one of the devices.

7. The method of claim 6, wherein the behavioral target is at least one of a limit on data write cycle count and a limit on a data age.

8. The method of claim 1, wherein the monitor data is write protected for preventing the monitor data from being overwritten with user data.

9. The method of claim 6, further comprising updating the behavioral target for the at least one of the devices after a period of time has elapsed.

10. The method of claim 1, wherein the memory devices are NAND devices.

11. The method of claim 1, wherein the monitor data comprises less than about 1% of a memory capacity of each of the memory devices, wherein the monitor data is write protected for preventing the monitor data from being overwritten with user data.

12. The method of claim 1, wherein the monitor data in each of the memory devices is written to multiple groups of blocks, wherein a number of write cycles performed for each group is different.

13. A computer program product, comprising:

a non-transitory computer usable medium having computer usable program code embodied therewith, the computer usable program code comprising;

computer usable program code configured to gather information about the monitor data from a plurality of memory devices having finite endurance and/or retention, the monitor data being;

(i) data of known content stored in dedicated memory cells of known write cycle count, (ii) write protected for preventing the monitor data from being overwritten with user data and (iii) write protected for preventing the monitor data from being overwritten with user data;

wherein the information about the monitor data includes error rate information relating to the data age of the monitor data;

computer usable program code configured to analyze the information about the monitor data; and

computer usable program code configured to take an action relating to at least one of the devices based on the analyzing.

14. A method, comprising:

gathering information about monitor data from a plurality of memory devices having finite endurance and/or retention, the monitor data being;

(i) data of known content stored in dedicated memory cells of known write cycle count, (ii) not subject to wear leveling, and (iii) write protected for preventing the monitor data from being overwritten with user data;

wherein the information about the monitor data includes error rate information relating to the data age of the monitor data;

analyzing the information about the monitor data; and

setting a behavioral target for at least one of the devices based on the analyzing.

15. The method of claim 14, wherein the monitor data is write protected for preventing the monitor data from being overwritten with user data.

16. The method of claim 14, wherein the information about the monitor data includes error rate information relating to at least one of the data age of the monitor data and the write cycle count.

17. The method of claim 14, further comprising performing the gathering and analyzing steps at least twice, and generating a statistical trend based thereon.

18. The method of claim 14, further comprising performing the gathering and analyzing steps at least twice, and tracking a time-dependence of the monitor data.

19. The method of claim 14, wherein the behavioral target is a limit on data write cycle count.

20. The method of claim 14, wherein the behavioral target is a limit on data age.

21. A system, comprising:

a plurality of memory devices having finite endurance and/or retention, each of the memory devices having;

a plurality of memory blocks, at least one of the blocks having monitor data written therein,

wherein the at least one block has been written to a plurality of times prior to writing the monitor data,

wherein the monitor data is;

(i) data of known content stored in dedicated memory cells of known write cycle count, (ii) write protected for preventing the monitor data from being overwritten with user data, and (iii) not subject to wear leveling; and

circuitry for addressing the blocks;

a processor in communication with the memory devices, the processor being configured to gather information about the monitor data from the memory devices, analyze the information about the monitor data and take an action relating to at least one of the devices based on the analyzing; and

a clock, the processor being in communication with the clock.

22. The system of claim 21, further comprising a secondary memory storing a copy of the monitor data.

23. The system of claim 21, further comprising a non-transitory computer usable medium, the computer usable medium having computer usable program code embodied therewith, which when executed by a processor causes the processor to:

gather information about the monitor data from a plurality of memory devices having finite endurance and/or retention, the monitor data being data of known content stored in dedicated memory cells of known write cycle count;

analyze the information about the monitor data; and

take an action relating to at least one of the devices based on the analyzing.

24. The system of claim 21, wherein the memory devices are NAND devices.