Near instantaneous backup and restore of disc partitions

• US 20080201536A1
• Filed: 02/16/2007
• Published: 08/21/2008
• Est. Priority Date: 02/16/2007
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Hars, Laszlo
• Granted Patent: US 7,577,803 B2
• Time in Patent Office: Days
• US Class Current: 711/154
• CPC Class Codes: G06F 11/1451 by selection of backup contents
• CPC Class Codes: G06F 11/1456 Hardware arrangements for backup
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 11/2084 on the same storage unit
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99954 Version management

Abstract

An apparatus comprises a data storage medium including first and second partitions, wherein individual physical blocks in the first partition are paired with individual physical blocks in the second partition, a status flag for each of the pairs of physical blocks, and a controller for performing read and write operations on the physical blocks in accordance with the status flags. A method performed by the apparatus is also provided.

Claims

1. An apparatus comprising:

a data storage medium including first and second partitions, wherein individual physical blocks in the first partition are paired with individual physical blocks in the second partition;

a status flag for each of the pairs of physical blocks; and

a controller for performing read and write operations on the physical blocks in accordance with the status flags.

2. The apparatus of claim 1, wherein the status flags identify a status comprising one of:

garbage, data, backup and live.

3. The apparatus of claim 2, wherein in response to a backup operation, a backup status changes to a garbage status and a live status changes to a data status.

4. The apparatus of claim 2, wherein in response to a restore operation, a backup status changes to a data status and a live status changes to a garbage status.

5. The apparatus of claim 2, wherein read operations can only be performed on physical blocks having a data or live status, and the status flags do not change for read operations.

6. The apparatus of claim 2, wherein write operations can only be performed on the physical blocks having a garbage or live status, and each write operation changes a garbage status to a live status and a data status to a backup status.

7. The apparatus of claim 1, further comprising:

non-volatile memory for storing the status flags.

8. The apparatus of claim 1, further comprising:

volatile memory for storing the status flags, with disc rotation energy used to store the status flags in the data storage medium, in case of a loss of power.

9. The apparatus of claim 1, further comprising:

a plurality of logical block addresses, each of the logical block addresses corresponding to a pair of the physical block addresses.

10. The apparatus of claim 1, further comprising:

a third partition having physical blocks paired with the physical blocks in the first partition.

11. A method comprising:

providing first and second sets of physical blocks in a storage medium, wherein individual physical blocks in the first set are paired with individual physical blocks in the second set;

providing a status flag for each of the pairs of physical blocks;

performing an operation on one of the physical blocks in accordance with the status flag; and

changing the status flags in response to the operation performed.

12. The method of claim 11, wherein the status flags identify a status comprising one of:

garbage, data, backup and live.

13. The method of claim 12, wherein in response to a backup operation, a backup status changes to a garbage status and a live status changes to a data status.

14. The method of claim 12, wherein in response to a restore operation, a backup status changes to a data status and a live status changes to a garbage status.

15. The method of claim 12, wherein read operations can only be performed on the physical blocks having a data or live status.

16. The method of claim 12, wherein write operations can only be performed on the physical blocks having a garbage or live status, and each write operation changes a garbage status to a live status and a data status to a backup status.

17. The method of claim 11, wherein the first and second sets of physical blocks are allocated when partitioning a data storage medium for supporting fast backup and restore operations.

18. The method of claim 11, further comprising:

moving data in a background operation to create contiguous live and backup partitions, with a hierarchical system of sections, controlled by clean/dirty flags.

19. The method of claim 11, further comprising:

issuing a backup-read host command.

20. The method of claim 11, wherein backup and restore operations are performed during a boot sequence.