Reducing rebuild time in a computing storage environment

Patent metadata

Field	Value
Publication number	US-11074130-B2
Application number	US-201916367245-A
Country	US
Kind code	B2
Filing date	Mar 28, 2019
Priority date	Mar 28, 2019
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

Embodiments for reducing rebuild time in a computing storage environment in by a processor. One or more disk drive failures in a Redundant Array of Independent Disks (RAID)- 6 may be rebuilt by holding at least three parity strips per stripe while using one or more of the at least three parity strips according the one or more disk drive failures.

First claim

The invention claimed is:

1. A method, by a processor, for data recovery in a computing system, comprising:
rebuilding a Redundant Array of Independent Disks (RAID)- 6 arranged as a single array subsequent to one or more disk drive failures by holding at least three parity strips per stripe and using one or more of the least three parity strips according to a location in the single array the one or more disk drive failures occurred, wherein two of the at least three parity strips are P parity strips, and wherein a first of the two P parity strips is assigned to a first section of the stripe and a second of the two P parity strips is assigned to a second section of the stripe.

2. The method of claim 1 , further including using a first parity strip of the at least three parity strips in a first parity-stripe of the stripe, wherein the first parity strip of the first parity-stripe is the first of the two P parity strips.

3. The method of claim 1 , further including using a second parity strip of the at least three parity strips in a second parity-stripe of the stripe, wherein the second parity strip of the second parity-stripe is the second of the two P parity strips.

4. The method of claim 1 , further including using a third parity strip of the at least three parity strips at the end of the stripe, wherein the third parity strip is a Q parity strip.

5. The method of claim 1 , further including rebuilding a selected portion of the stripe having a single disk drive failure and associated with a first parity strip of the at least three parity strips.

6. The method of claim 1 , further including rebuilding the stripe having one or more disk drive failures and associated with one or more of the at least three parity strips according to a defined rebuild order.

7. The method of claim 1 , further including:
rebuilding a Q parity strip, a data strip or a single parity strip for a single disk failure upon occurrence of a single disk drive failure;
rebuilding the Q parity strip and the data strip or the single parity strip or at least two data strips or parity strips occurring in a similar p-stripe associated with one or more of the two parity strips upon occurrence of at least two disk drive failures; or
rebuilding the Q parity strip and the data strip in each section of the stripe associated with the two parity strips upon occurrence of at least three or more disk drive failures.

8. A system for data recovery in a computing environment, comprising:
one or more computers with executable instructions that when executed cause the system to:
rebuild a Redundant Array of Independent Disks (RAID)- 6 arranged as a single array subsequent to one or more disk drive failures by holding at least three parity strips per stripe and using one or more of the least three parity strips according to a location in the single array the one or more disk drive failures occurred, wherein two of the at least three parity strips are P parity strips, and wherein a first of the two P parity strips is assigned to a first section of the stripe and a second of the two P parity strips is assigned to a second section of the stripe.

9. The system of claim 8 , wherein the executable instructions use a first parity strip of the at least three parity strips in a first parity-stripe of the stripe, wherein the first parity strip of the first parity-stripe is the first of the two P parity strips.

10. The system of claim 8 , wherein the executable instructions use a second parity strip of the at least three parity strips in a second parity-stripe of the stripe, wherein the second parity strip of the second parity-stripe is the second of the two P parity strips.

11. The system of claim 8 , wherein the executable instructions use a third parity strip of the at least three parity strips at the end of the stripe, wherein the third parity strip is a Q parity strip.

12. The system of claim 8 , wherein the executable instructions rebuild a selected portion of the stripe having a single disk drive failure and associated with a first parity strip of the at least three parity strips.

13. The system of claim 8 , wherein the executable instructions rebuild the stripe having one or more disk drive failures and associated with one or more of the at least three parity strips according to a defined rebuild order.

14. The system of claim 8 , wherein the executable instructions:
rebuild a Q parity strip, a data strip or a single parity strip for a single disk failure upon occurrence of a single disk drive failure;
rebuild the Q parity strip and the data strip or the single parity strip or at least two data strips or parity strips occurring in a similar p-stripe associated with one or more of the two parity strips upon occurrence of at least two disk drive failures; or
rebuild the Q parity strip and the data strip in each section of the stripe associated with the two parity strips upon occurrence of at least three or more disk drive failures.

15. A computer program product for, by a processor, data recovery in a computing system, the computer program product comprising a non-transitory computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising:
an executable portion that rebuilds a Redundant Array of Independent Disks (RAID)- 6 arranged as a single array subsequent to one or more disk drive failures by holding at least three parity strips per stripe and using one or more of the least three parity strips according to a location in the single array the one or more disk drive failures occurred, wherein two of the at least three parity strips are P parity strips, and wherein a first of the two P parity strips is assigned to a first section of the stripe and a second of the two P parity strips is assigned to a second section of the stripe.

16. The computer program product of claim 15 , further including an executable portion that:
uses a first parity strip of the at least three parity strips in a first parity-stripe of the stripe, wherein the first parity strip of the first parity-stripe is the first of the two P parity strips; or
uses a second parity strip of the at least three parity strips in a second parity-stripe of the stripe, wherein the second parity strip of the second parity-stripe is the second of the two P parity strips.

17. The computer program product of claim 15 , further including an executable portion that uses a third parity strip of the at least three parity strips at the end of the stripe, wherein the third parity strip is a Q parity strip.

18. The computer program product of claim 15 , further including an executable portion that rebuilds a selected portion of the stripe having a single disk drive failure and associated with a first parity strip of the at least three parity strips.

19. The computer program product of claim 15 , further including an executable portion that rebuilds the stripe having one or more disk drive failures and associated with one or more of the at least three parity strips according to a defined rebuild order.

20. The computer program product of claim 15 , further including an executable portion that:
rebuilds a Q parity strip, a data strip or a single parity strip for a single disk failure upon occurrence of a single disk drive failure;
rebuilds the Q parity strip and the data strip or the single parity strip or at least two data strips or parity strips occurring in a similar p-stripe associated with one or more of the two parity strips upon occur

Assignees

• IBM

Inventors

• Shatsky Yosef
• Porat-Stoler Asaf
• Leneman Ofer
• Marenkov Sergey

Classifications

• G06F11/1088 Primary

  Reconstruction on already foreseen single or plurality of spare disks · CPC title

• G06F3/0619

  in relation to data integrity, e.g. data losses, bit errors · CPC title

• G06F3/0689

  Disk arrays, e.g. RAID, JBOD · CPC title

• G06F11/1092 Primary

  Rebuilding, e.g. when physically replacing a failing disk · CPC title

• G06F3/0644

  Management of space entities, e.g. partitions, extents, pools · CPC title