SNAPSHOT CREATION

• US 20170300505A1
• Filed: 12/15/2014
• Published: 10/19/2017
• Est. Priority Date: 10/28/2014
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Inventors: Belmanu Sadananda, Girish Chandra, Balaraj, Santosh Bangalore, Slater, Alastair, Nallusamy, Subramani
• Granted Patent: US 10,268,695 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 11/14 Error detection or correction of the data by redundancy in operation G06F11/16 takes precedence
• CPC Class Codes: G06F 11/1446 Point-in-time backing up or restoration of persistent data
• CPC Class Codes: G06F 11/1461 Backup scheduling policy
• CPC Class Codes: G06F 11/1474 in transactions G06F16/20 takes precedence
• CPC Class Codes: G06F 16/128 Details of file system snapshots on the file-level, e.g. snapshot creation, administration, deletion use of snapshots for error detection or correction G06F11/14, G06F11/16
• CPC Class Codes: G06F 16/1756 based on delta files
• CPC Class Codes: G06F 2201/81 Threshold
• CPC Class Codes: G06F 2201/815 Virtual
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data

Abstract

In one example an updated snapshot delta value is computed upon occurrence of a new transaction. The new transaction is a data modification operation performed on data blocks of the storage device. Further, the delta value indicates at least one of volume of data modified since creation of a reference snapshot and number of transactions performed since the creation. Subsequently, the updated snapshot delta value is compared with a corresponding threshold value. The threshold value is at least one of a predetermined volume of data modified and a predetermined number of transactions. A snapshot action is subsequently performed based on the comparison.

Claims

1. A method comprising:

computing an updated snapshot delta value upon occurrence of a new transaction;

wherein the snapshot delta value indicates at least one of volume of data modified since creation of a reference snapshot and number of transactions performed since creation of the reference snapshot, and wherein the new transaction is a data modification operation performed on data blocks of a storage device;

comparing the updated snapshot delta value with a corresponding threshold value, wherein the threshold value is at least one of a predetermined volume of data modified and a predetermined number of transactions; and

performing a snapshot action based on the comparison.

2. The method as claimed in claim 1, wherein the snapshot delta value is one of a snapshot delta count, a snapshot-replicate value, a snapshot-backup value, and a snapshot-expire value.

3. The method of claim 2, wherein the snapshot action is at least one of:

creating a new snapshot if the snapshot delta value is the snapshot delta count;

creating a replicated volume snapshot of the reference snapshot if the snapshot delta value is the snapshot-replicate value;

adding the reference snapshot to a backup disk is the snapshot delta value is the snapshot-backup value; and

deleting the reference snapshot if the snapshot delta value is the snapshot-expire value.

4. The method of claim 1, wherein the computing further comprising:

determining volume of data modified during the new transaction;

incrementing a last value of a snapshot delta count by one of the volume of data modified and number of transactions currently occurred to obtain an updated value of the snapshot delta count, wherein the value of the snapshot delta count indicates at least one of volume of data modified since a last reset of the snapshot delta count and number of transactions performed since the last reset; and

compute the updated snapshot delta value based on the updated value of the snapshot delta count and a delta reset count, wherein the delta reset count indicates number of times the snapshot delta count has been reset since creation of the reference snapshot.

5. The method as claimed in claim 4, wherein the method further comprising:

determining the updated value of the snapshot delta count to be greater than the corresponding threshold;

resetting the snapshot delta count to zero; and

incrementing a last value of the delta reset count by a numerical value of one to obtain an updated value of the delta reset count.

6. A computing system comprising:

a processor;

a delta counter coupled to the processor to;

compute an updated value of a snapshot delta count upon occurrence of a new transaction, wherein the value of the snapshot delta count indicates one of volume of data modified since a last reset of the snapshot delta count and number of transactions performed since the last reset, and wherein the new transaction includes a data modification operation performed on data blocks of a storage device of the computing system; and

a snapshot updating module coupled to the processor to;

compare the updated value of the snapshot delta count with a corresponding threshold value, wherein the threshold value specifies one of a predetermined volume of data modified and a predetermined number of transactions; and

on determining the updated value of the snapshot delta count to be greater than the threshold value, create a new snapshot.

7. The computing system as claimed in claim 6, wherein the delta counter further is to:

determine volume of data modified during the new transaction; and

increment a last value of the snapshot delta count by one of the volume of data modified and number of transactions currently occurred to obtain the updated value of the snapshot delta count.

8. The computing system as claimed in claim 7, wherein the snapshot updating module further is to:

compute an updated snapshot delta value based on the updated value of the snapshot delta count and a delta reset count to obtain, wherein the snapshot delta value indicates at least one of volume of data modified since creation of a reference snapshot and number of transactions performed since creation of the reference snapshot, and wherein the delta reset count indicates number of times the snapshot delta count has been reset since creation of the reference snapshot; and

compare the updated snapshot delta value with the corresponding threshold value to determine if a snapshot action has to be performed.

9. The computing system as claimed in claim 8, wherein on determining the updated snapshot delta value to be greater than the corresponding threshold value, the snapshot updating module further is to:

create a replicated volume snapshot of the reference snapshot if the snapshot delta value is the snapshot-replicate value;

add the reference snapshot to a backup disk if the snapshot delta value is the snapshot-backup value; and

delete the reference snapshot if the snapshot delta value is the snapshot-expire value.

10. The computing system as claimed in claim 6 further comprising a delta reset counter coupled to the processor to:

determine the snapshot delta count to have been reset to zero; and

increment a last value of the delta reset count by a numerical value of one to obtain an updated value of the delta reset count, wherein the delta reset count indicates number of times the snapshot delta count has been reset since creation of the reference snapshot.

11. The computing system as claimed in claim 6, wherein the snapshot updating module further is to:

determine occurrence of a snapshot update condition, wherein the snapshot update condition is at least one of;

number of errors detected in the storage device being greater than a predetermined error threshold;

occurrence of a change in characteristics of reference snapshot saved in the storage device; and

number of the reference snapshot being less than a minimum snapshot threshold; and

create the new snapshot occurrence of the snapshot update condition.

12. A non-transitory computer readable medium having a set of computer readable instructions that, when executed, cause a processor to:

compute an updated snapshot delta value upon occurrence of a new transaction, wherein the snapshot delta value indicates at least one of volume of data modified since creation of a reference snapshot and number of transactions performed since creation of the reference snapshot, and wherein the new transaction is a data modification operation performed on data blocks of the storage device;

compare the updated snapshot delta value with a corresponding threshold value;

wherein the threshold value is at least one of a predetermined volume of data modified and a predetermined number of transactions; and

on determining the updated snapshot delta value to be greater than the threshold value;

perform a snapshot action, wherein the snapshot action is at least one of;

creating a new snapshot if the snapshot delta value is a snapshot delta count;

creating a replicated volume snapshot of the reference snapshot if the snapshot delta value is a snapshot-replicate value;

adding the reference snapshot to a backup disk is the snapshot delta value is a snapshot-backup value; and

deleting the reference snapshot if the snapshot delta value is a snapshot-expire value.

13. The non-transitory computer readable medium of claim 12, wherein the snapshot delta value is one of the snapshot delta count, the snapshot-replicate value, the snapshot-backup value, and the snapshot-expire value.

14. The non-transitory computer readable medium of claim 12, wherein the computer readable instructions, when executed, further cause the processor to:

determine volume of data modified during the new transaction;

increment a last value of a snapshot delta count by one of the volume of data modified and number of transactions currently occurred to obtain an updated value of the snapshot delta count, wherein the value of a snapshot delta count indicates at least one of volume of data modified since a last reset of the snapshot delta count and number of transactions performed since the last reset; and

compute the updated snapshot delta value based on the updated value of the snapshot delta count and a delta reset count, wherein the delta reset count indicates number of times the snapshot delta count has been reset since creation of the reference snapshot.

15. The non-transitory computer readable medium of claim 12, wherein the computer readable instructions, when executed;

further cause the processor to;

determine the updated value of the snapshot delta count to be greater than the corresponding threshold;

reset the snapshot delta count to zero; and

increment a last value of the delta reset count by a numerical value of one to obtain an updated value of the delta reset count.