System, method, and computer program product for increasing spare space in memory to extend a lifetime of the memory

• US 9,645,750 B2
• Filed: 11/09/2015
• Issued: 05/09/2017
• Est. Priority Date: 11/28/2007
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Danilak, Radoslav
• Primary Examiner(s): DUDEK JR, EDWARD J
• Application Number:
  US14/936,638
• Publication Number:
  US 20160062684A1
• Time in Patent Office: 547 Days
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 2212/1036 Life time enhancement
• CPC Class Codes: G06F 2212/1044 Space efficiency improvement
• CPC Class Codes: G06F 2212/401 Compressed data
• CPC Class Codes: G06F 2212/7204 Capacity control, e.g. partitioning, end-of-life degradation
• CPC Class Codes: G06F 2212/7205 Cleaning, compaction, garbage collection, erase control
• CPC Class Codes: G06F 2212/7206 Reconfiguration of flash memory system
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/0616 in relation to life time, e.g. increasing Mean Time Between Failures [MTBF]
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0641 De-duplication techniques
• CPC Class Codes: G06F 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

A method including increasing spare space in a storage subsystem including a flash memory, wherein the storage subsystem includes compressed data stored in the flash memory; extending a lifetime of the storage subsystem to achieve a stored selected minimum lifetime, based at least in part as a result of the increasing spare space; identifying at least one aspect associated with the lifetime of the storage subsystem; and delaying, based at least upon one identified aspect, at least one operation that reduces the lifetime of the storage subsystem, wherein the delaying at least one operation includes delaying a command that initiates the at least one operation.

Claims

1. A method comprising:

increasing spare space in a storage subsystem comprising a flash memory, wherein the storage subsystem comprises compressed data stored in the flash memory;

extending a lifetime of the storage subsystem to achieve a stored selected minimum lifetime, based at least in part as a result of the increasing of the spare space;

identifying at least one aspect associated with the lifetime of the storage subsystem; and

delaying, based at least upon one identified aspect, at least one operation that reduces the lifetime of the storage subsystem, wherein the delaying the at least one operation comprises delaying a command that initiates the at least one operation.

2. The method of claim 1, wherein the at least one aspect comprises a period of time, a rate of the operations that reduce the lifetime of the flash memory, a total permitted number of the operations that reduce the lifetime of the flash memory, and a duration of the lifetime.

3. The method of claim 1, wherein the compressed data is based on loss-less compressing.

4. The method of claim 1, wherein the compressed data is based on lossy compressing.

5. The method of claim 1, wherein the flash memory comprises a plurality of blocks, and the increasing the spare space further comprises increasing a number of spare blocks of the plurality of blocks.

6. The method of claim 5, further comprising:

equalizing an end of life of the plurality of blocks; and

increasing the spare space by removing duplicate data stored in the flash memory.

7. The method of claim 1, wherein the flash memory includes at least one of a single-bit per cell NOR flash memory, a multi-bit per cell NOR flash memory, a single-bit per cell NAND flash memory, and a multi-bit per cell NAND flash memory.

8. A non-transitory tangible computer readable medium having a set of instructions stored therein that when executed by a processing element cause the processing element to perform and/or control operations comprising:

increasing spare space in a storage subsystem comprising a flash memory, the flash memory comprising compressed data, wherein the increasing the spare space further comprises detecting deleted data and increasing space with space occupied with the deleted data;

extending a lifetime of the storage subsystem to achieve a stored selected minimum lifetime based at least in part as a result of the increasing of the spare space; and

delaying at least one operation that reduces the lifetime of the storage subsystem based on a delaying scheme.

9. The non-transitory tangible computer readable medium of claim 8, wherein the delaying scheme is based at least on an application priority scheme based on at least one selected from a group consisting of an application that initiates the operation, an operation grouping scheme based on similar types of operations, and excess operations.

10. The non-transitory tangible computer readable medium of claim 8, wherein the compressed data is based on loss-less compressing.

11. The non-transitory tangible computer readable medium of claim 8, wherein the compressed data is based on lossy compressing.

12. The non-transitory tangible computer readable medium of claim 8, wherein the flash memory comprises a plurality of blocks, and the increasing the spare space further comprises increasing a number of spare blocks of the plurality of blocks.

13. The non-transitory tangible computer readable medium of claim 12, further comprising:

equalizing an end of life of the plurality of blocks; and

increasing the spare space by removing duplicate data stored in the flash memory.

14. The non-transitory tangible computer readable medium of claim 8, wherein the flash memory includes at least one of a single-bit per cell NOR flash memory, a multi-bit per cell NOR flash memory, a single-bit per cell NAND flash memory, and a multi-bit per cell NAND flash memory.

15. A storage system comprising:

a flash memory comprising compressed data;

a storage subsystem;

logic for increasing spare space in the flash memory;

logic for extending a lifetime of the storage subsystem to achieve a stored selected minimum lifetime, based at least in part as a result of the increasing the spare space to comprise an increased amount of the flash memory; and

logic for delaying at least one operation that reduces the lifetime of the storage subsystem based on a delaying scheme.

16. The storage system of claim 15, wherein logic for the delaying scheme is based at least on an application priority scheme based on at least one selected from a group consisting of an application that initiates the operation, an operation grouping scheme based on similar types of operations, and excess operations.

17. The storage system of claim 15, wherein the compressed data is based on loss-less compressing.

18. The storage system of claim 15, wherein the compressed data is based on lossy compressing.

19. The storage system of claim 15, wherein the flash memory comprises:

a plurality of blocks; and

the increasing the spare space further comprises increasing a number of spare blocks of the plurality of blocks,

wherein the flash memory includes at least one of a single-bit per cell NOR flash memory, a multi-bit per cell NOR flash memory, a single-bit per cell NAND flash memory, and a multi-bit per cell NAND flash memory.

20. The storage system of claim 19, further comprising:

equalizing an end of life of the plurality of blocks; and

increasing the spare space by removing duplicate data stored in the flash memory.