Systems and methods for analyzing snapshots

• US 8,433,682 B2
• Filed: 12/27/2010
• Issued: 04/30/2013
• Est. Priority Date: 12/31/2009
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Ngo, David
• Primary Examiner(s): Trujillo, James
• Assistant Examiner(s): Chang, Jeffrey
• Application Number:
  US12/978,984
• Publication Number:
  US 20110161295A1
• Time in Patent Office: 855 Days
• Field of Search: 707/639
• US Class Current: 707/639
• CPC Class Codes: G06F 11/1446 Point-in-time backing up or restoration of persistent data
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1461 Backup scheduling policy
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 16/2477 Temporal data queries
• CPC Class Codes: G06F 2201/80 Database-specific techniques
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data

Abstract

This application describes techniques for creating a second snapshot of a first snapshot of a set of data, modifying the first snapshot, and reverting the modifications to the first snapshot. For example, portions of one or more transaction logs may be played into a database to put the database in a particular state a particular point in time. The second snapshot may then be used to revert to a prior state of the database such that additional transaction logs may be played into the database. These techniques enable the ability to put the database into multiple states as the database existed at multiple points in time. Therefore, data can be recovered from the database as the data existed at different points in time. Moreover, individual data objects in the database can be accessed and analyzed as the individual data objects existed at different points in time.

Claims

1. A system for analyzing a snapshot of a set of data, the system comprising:

a processor;

a memory;

a copy component configured to create a full copy of the set of data, and to create a copy of a log of changes made to the set of data after the full copy of the set of data was made,

wherein the set of data includes multiple data objects;

a snapshot component configured to

create a first snapshot of the set of data at a first time,

wherein the first snapshot includes a first logical copy capturing a first state of the set of data at the first time, and

wherein the first snapshot includes pointers to data in the set of data;

create a copy of the first snapshot at a second time,

wherein the second time is after the first time and wherein the copy includes a copy of the pointers to a copy of data representing at least some of the first snapshot; and

an interface and analysis component configured to

receive a user request to access, via the first snapshot, at least one of the multiple data objects included in the first logical copy of the set of data;

access, based on the received user request, the at least one of the multiple data objects included in the first logical copy of the set of data

wherein the access includes modifying the full copy of the set of data based on the first snapshot, the log of changes, or both the first snapshot and the log of changes; and

wherein the snapshot component is further configured to create, prior to the access, a snapshot of the copy of the first snapshot and associated transaction logs;

wherein the system is further configured to

receive an instruction to change at least a portion of the set of data to an other state; and

change the set of data to the other state of based at least in part on the second snapshot.

2. The system of claim 1, wherein the snapshot component modifies the first snapshot before creating the second snapshot.

3. The system of claim 1, wherein the snapshot component modifies the first snapshot after creating the second snapshot.

4. The system of claim 1, wherein the set of data includes a database and database logs, and wherein the snapshot component modifies the first snapshot by playing one or more database logs into the database.

5. The system of claim 1, wherein the snapshot component reverts to the second state of the set of data by performing a revert operation utilizing the second snapshot.

6. The system of claim 1, wherein the set of data is associated with an application, and wherein the application includes either an email server, a Structured Query Language (SQL) server, a file server, or an application server.

7. The system of claim 1, wherein the snapshot component is further configured to, after reverting to the second state of the set of data, modify the first snapshot a second time.

8. The system of claim 1, further comprising a component configured to perform at least one operation on the accessed multiple data objects, wherein performing the at least one operation includes either

indexing the accessed multiple data objects and adding information to an index;

associating the accessed multiple data objects with one or more classifications and storing the one or more classifications in a metabase;

or

extracting the accessed multiple data objects from the set of data and copying the multiple data objects to a storage device.

9. A method for analyzing a snapshot of a set of data, wherein the method is performed by a computing system having a processor and memory, the method comprising:

creating, by the computing system, a first snapshot of a set of data at a first time, wherein the first snapshot includes a first logical copy of the set of data that captures a first state of the set of data at the first time, and wherein the set of data includes multiple data objects;

modifying the first snapshot;

creating a copy of the first snapshot at a second time, wherein the copy includes a copy of the pointers to a second logical copy of the first snapshot that captures a second state of the set of data at the second time;

receiving a user request to access at least one of the multiple data objects;

creating, prior to accessing the at least one of the multiple data objects, a snapshot of the copy of the first snapshot and associated transaction logs;

accessing, via the first snapshot, the multiple data objects included in the first logical copy of the set of data;

analyzing the accessed multiple data objects; and

reverting to the second state of the set of data.

10. The method of claim 9, wherein modifying the first snapshot occurs before creating the second snapshot.

11. The method of claim 9, wherein modifying the first snapshot occurs after creating the second snapshot.

12. The method of claim 9, wherein creating the first snapshot of the set of data includes creating the first snapshot of the set of data at least partly with a software-based snapshot provider.

13. The method of claim 9, wherein creating the first snapshot of the set of data includes creating the first snapshot of the set of data at least partly with a hardware-based snapshot provider.

14. The method of claim 9, wherein the set of data includes a database and database logs, and wherein modifying the first snapshot includes playing one or more database logs into the database.

15. The method of claim 9, wherein reverting to the second state of the set of data includes performing a revert operation utilizing the second snapshot.

16. The method of claim 9, wherein the set of data is utilized by an application, and wherein the application includes either an email server, a Structured Query Language (SQL) server, a file server, or an application server.

17. The method of claim 9, further comprising, after reverting to the second state of the set of data, modifying the first snapshot a second time.

18. The method of claim 9, further comprising performing at least one operation on the accessed one or more multiple data objects, wherein performing the at least one operation includes either

indexing the multiple data objects and adding information to an index;

associating the multiple data objects with one or more classifications and storing the one or more classifications in a metabase;

or

extracting the multiple data objects from the set of data and copying the multiple data objects to a storage device.

19. A tangible computer-readable storage medium storing a computer-executable method for analyzing a set of data, wherein the set of data includes multiple data objects, the method comprising:

receiving a request to access one of the multiple data objects from the set of data;

accessing a full copy of the set of data, wherein the full copy of the set of data represents a state of the set of data at a time t₀, but the one data object was modified after the time t₀;

accessing at least one log of changes made to the set of data,

wherein the log includes changes made to the one data object after the time t_o;

accessing a first snapshot of the full set of data,

wherein the first snapshot was made at a first time t₁ after the time t₀,

wherein the first snapshot includes a first logical copy of the set of data to thereby capture a first state of the set of data at the time t₁;

creating a copy of the first snapshot at a second time t₂,

wherein the second time is after than the first time, and

wherein the copy includes a copy of data representing at least some of the first snapshot and a copy of the pointers of the first snapshot;

receiving a user request to access at least one of the multiple data objects;

creating, prior to accessing the at least one of the multiple data objects, a snapshot of the copy of the first snapshot and associated transaction logs;

accessing the one data object via (i) the first snapshot, (ii) the log of changes made to the set of data, and (iii) the full copy of the set of data,

wherein the accessing is performed after creating the second snapshot, and

wherein the one data object is obtained after at least some of the changes identified in the log and represented by the first snapshot are made to the full copy of the data set; and

,

reverting to the full copy of the set of data to the state at the time t₀ and permitting further access to data objects changed after the time t₀ based on the second snapshot,

wherein after the changes represented by the first snapshot are made to the full copy of the data set, access to data objects changed after the time t₀ are not possible without access to the second snapshot.

20. A system for analyzing a snapshot of a set of data, the system comprising:

a processor;

a memory;

means for creating and modifying snapshots, wherein the means for creating and modifying snapshots is configured to

create a first snapshot of a set of data at a first time, wherein the first snapshot includes a first logical copy of the set of data that captures a first state of the set of data at the first time, and wherein the set of data includes multiple data objects;

modify the first snapshot; and

create a copy of the first snapshot at a second time, wherein the copy includes a second logical copy of the first snapshot that captures a second state of the set of data at the second time; and

means for accessing and analyzing data objects, wherein the means for accessing and analyzing data objects is configured to

access, via the first snapshot, the multiple data objects included in the first logical copy of the set of data; and

analyze the accessed multiple data objects,

wherein the means for creating and modifying snapshots is further configured to

create, prior to the access, a snapshot of the copy of the first snapshot and associated transaction logs, and

receive an instruction to revert to the second state of the set of data; and

revert to the second state of the set of data.

21. A method for analyzing a set of data, wherein the set of data includes multiple data objects, the method comprising:

creating a full copy of the set of data at a first time;

creating a full copy of the set of data at a second time after the first time;

creating at least one log of changes made to the set of data between the first time and the second time;

after the first time and before the second time, creating multiple snapshots that include logical copies each representing a different state of the set of data after the first time and before the second time;

identifying a point in time to obtain a copy of at least one data object in the set of data, wherein the point in time is after the first time and before the second time, and wherein the one data object was changed after the first time and before the second time;

accessing, via one of the multiple snapshots and the log and/or the full copy of the set of data at the first time, the one data object as changed after the first time and before the second time; and

,

before accessing the one data object, creating a copied snapshot of the one of multiple snapshots, and,

but for the copied snapshot, subsequent access to at least some of the data objects in the set of data as changed between the first time and the second time would not be possible.

22. A method for analyzing data, wherein the method is performed by a computing system having a processor and memory, the method comprising:

receiving replication logs indicating changes to first data, wherein

the first data includes multiple individual data objects,

the replication logs can be utilized to replicate the changes to second data that is a copy of the first data as the first data existed at a first point in time, and

the replication logs include at least one marker indicating a second point in time at which the first data is consistent;

utilizing, by the computing system, at least some of the replication logs to replicate at least some of the changes to the second data;

upon reaching the at least one marker in the replication logs, creating a snapshot of the second data changed according to the replication logs;

analyzing the snapshot of the second data changed according to the replication logs; and

accessing one or more of the multiple individual data objects as the multiple individual data objects existed at the second point in time.

23. The method of claim 22 wherein the second data includes a database and at least one database log, wherein the replication logs include modifications to the database and/or the at least one database log, and wherein utilizing the replication logs to replicate the changes to the second data includes modifying the database using the at least one database log.

24. The method of claim 22 wherein analyzing the snapshot of the second data includes performing at least one modification to the snapshot of the second data, and wherein the method further comprises:

after analyzing the snapshot of the second data, reverting the snapshot of the second data; and

after reverting the snapshot of the second data, utilizing at least some of the replication logs to replicate additional changes to the second data.

25. The method of claim 22, further comprising after creating the snapshot of the second data, utilizing at least some of the replication logs to replicate additional changes to the second data.