Migrating stored copies of a file to stored encoded data slices

• US 8,904,226 B2
• Filed: 08/05/2011
• Issued: 12/02/2014
• Est. Priority Date: 08/26/2010
• Status: Active Grant

• Current Assignee: Pure Storage, Inc.
• Original Assignee: Cleversafe Incorporated (International Business Machines Corporation)
• Inventors: Resch, Jason K., Grube, Gary W., Markison, Timothy W.
• Primary Examiner(s): TRUONG, LOAN
• Application Number:
  US13/204,057
• Publication Number:
  US 20120054555A1
• Time in Patent Office: 1,215 Days
• Field of Search: 714/6.1, 714/6.13, 714/6.24, 714/41
• US Class Current: 714/6.1
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 12/0223 User address space allocation, e.g. contiguous or non contiguous base addressing
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

A method begins by a processing module identifying a set of stored files that includes an original file and one or more back-up copies of the original file. The method continues with the processing module dispersed storage error encoding one of the set of stored files to produce a plurality of sets of encoded data slices. The method continues with the processing module facilitating storage of the plurality of sets of encoded data slices. The method continues with the processing module facilitating deletion of the set of stored files.

Claims

1. A method comprises:

identifying a set of stored files that includes an original file and one or more back-up copies of the original file;

dispersed storage error encoding one of the set of stored files to produce a plurality of sets of encoded data slices;

facilitating storage of the plurality of sets of encoded data slices; and

facilitating deletion of the set of stored files, wherein at least some of the plurality of sets of encoded data slices overwrite at least a portion of a back-up copy of the one or more back-up copies.

2. The method of claim 1, wherein the identifying the set of stored files comprises at least one of:

determining content of the one or more back-up copies substantially matches content of the original file;

determining a function-based indicator of the one or more back-up copies substantially matches a function-based indicator of the original file;

determining a back-up indicator of the one or more back-up copies substantially identifies the original file; and

determining a back-up indicator of the original file identifies the one or more back-up copies.

3. The method of claim 1 further comprises:

dispersed storage error encoding the one of the set of stored files using a first set of dispersed storage error coding parameters to produce a plurality of sets of temporary encoded data slices;

temporarily storing the plurality of sets of temporary encoded data slices;

after storage of the plurality of sets of temporary encoded data slices, commencing deleting of the set of stored files; and

as memory becomes available due to the deleting of the set of stored files, facilitating the storage of the plurality of sets of encoded data slices in the memory.

4. The method of claim 3 further comprises:

after storage of the plurality of sets of encoded data slices, deleting the plurality of sets of temporary encoded data slices.

5. The method of claim 1, wherein the deleting the set of stored files comprises:

verifying storage of the plurality of sets of encoded data slices prior to deleting the set of stored files.

6. A method comprises:

identifying a stored back-up file of a stored original file;

facilitating deletion of the stored back-up file;

dispersed storage error encoding the stored original file to produce a plurality of sets of encoded data slices; and

facilitating storage of the plurality of sets of encoded data slices, wherein at least some of the plurality of sets of encoded data slices overwrite at least a portion of the stored back-up file.

7. The method of claim 6 further comprises:

after verification of the storage of the plurality of sets of encoded data slices, facilitating deletion of the original file.

8. The method of claim 6, wherein the identifying the stored back-up file comprises at least one of:

determining content of the stored back-up file substantially matches content of the stored original file;

determining a function-based indicator of the stored back-up file substantially matches a function-based indicator of the stored original file;

determining a back-up indicator of the stored back-up file substantially identifies the stored original file; and

determining a back-up indicator of the stored original file identifies the stored back-up file.

9. A memory system comprises:

memory that stores a set of stored files that includes an original file and one or more back-up copies of the original file; and

a processing module operable to;

identify the set of stored files;

dispersed storage error encode one of the set of stored files to produce a plurality of sets of encoded data slices;

facilitate storage of the plurality of sets of encoded data slices in the memory; and

facilitate deletion of the set of stored files from the memory, wherein at least some of the plurality of sets of encoded data slices overwrite at least a portion of a back-up copy of the one or more back-up copies.

10. The memory system of claim 9, wherein the processing module functions to identify the set of stored files by at least one of:

determining content of the one or more back-up copies substantially matches content of the original file;

determining a function-based indicator of the one or more back-up copies substantially matches a function-based indicator of the original file;

determining a back-up indicator of the one or more back-up copies substantially identifies the original file; and

determining a back-up indicator of the original file identifies the one or more back-up copies.

11. The memory system of claim 9, wherein the processing module further functions to:

dispersed storage error encode the one of the set of stored files using a first set of dispersed storage error coding parameters to produce a plurality of sets of temporary encoded data slices;

temporarily store the plurality of sets of temporary encoded data slices in the memory;

after storage of the plurality of sets of temporary encoded data slices, commence deletion of the set of stored files from the memory; and

as memory becomes available due to the deletion of the set of stored files, facilitate the storage of the plurality of sets of encoded data slices in the memory.

12. The memory system of claim 11, wherein the processing module further functions to:

after storage of the plurality of sets of encoded data slices, delete the plurality of sets of temporary encoded data slices from the memory.

13. The memory system of claim 9, wherein the processing module functions to delete the set of stored files by:

verifying storage of the plurality of sets of encoded data slices prior to deleting the set of stored files from the memory.

14. A memory system comprises:

memory that stores a set of stored files that includes an original file and one or more back-up copies of the original file; and

a processing module operable to;

identify a stored back-up file of a stored original file;

facilitate deletion of the stored back-up file from the memory;

dispersed storage error encode the stored original file to produce a plurality of sets of encoded data slices; and

facilitate storage of the plurality of sets of encoded data slices in the memory, wherein at least some of the plurality of sets of encoded data slices overwrite at least a portion of the stored back-up file.

15. The memory system of claim 14, wherein the processing module further functions to:

after verification of the storage of the plurality of sets of encoded data slices, facilitate deletion of the original file from the memory.

16. The memory system of claim 14, wherein the processing module functions to identify the stored back-up file by at least one of:

determining content of the stored back-up file substantially matches content of the stored original file;

determining a function-based indicator of the stored back-up file substantially matches a function-based indicator of the stored original file;

determining a back-up indicator of the stored back-up file substantially identifies the stored original file; and

determining a back-up indicator of the stored original file identifies the stored back-up file.