MANAGING COPIES OF DATA

• US 20080243939A1
• Filed: 03/31/2008
• Published: 10/02/2008
• Est. Priority Date: 12/22/2006
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Gokhale, Parag, Kottomtharayil, Rajiv, Lu, Jun
• Granted Patent: US 7,814,118 B2
• Time in Patent Office: Days
• US Class Current: 707/200
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1453 using de-duplication of the data
• CPC Class Codes: G06F 16/134 Distributed indices
• CPC Class Codes: Y10S 707/99934 Query formulation, input preparation, or translation
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

A method in a computer system for retrieving data from one of multiple copies of the data is provided, referred to as the data management system. The data management system receives a request identifying at least one data object to be accessed. Then, the data management system queries a metabase to locate data copies that contain the identified at least one data object, wherein the data copies are created from similar source data, and wherein for each data copy the metabase contains an indication of the availability of the copy relative to other copies. Next, the data management system determines one of the located data copies to use to access the identified at least one data object, wherein the determination is made based on the indicated availability contained in the metabase for each of the located data copies. Then, the data management system accesses the identified at least one data object using the determined one of the located data copies.

Claims

1. A method in a computer system for retrieving data from one of multiple copies of the data, the method comprising:

receiving a request identifying at least one data object to be accessed;

identifying multiple copies of the data object that satisfy the request;

for each identified copy, determining an availability of the copy relative to the other identified copies, wherein the availability at least includes a time to access the identified copy;

selecting an identified copy to use for accessing the identified at least one data object based at least in part on the determined availability of the identified copies; and

accessing the identified at least one data object using the selected copy.

2. The method of claim 1 wherein determining the availability of the copy includes at least determining a type of media on which the copy is stored.

3. The method of claim 1 wherein determining the availability of the copy includes at least determining a physical location where the copy is stored and identifying the copy as less available if it is stored at an offsite location than if it is stored at an onsite location.

4. The method of claim 1 wherein determining the availability of the copy includes at least determining whether the copy is encrypted and if the copy is encrypted identifying the copy as less available than a non-encrypted copy.

5. The method of claim 1 wherein determining the availability of the copy includes at least determining a tier of storage and type of hardware on which the copy is stored.

6. The method of claim 1 wherein determining the availability of the copy includes at least determining a network topology and identifying the availability of the copy based on the subnet on which the copy is stored.

7. The method of claim 1 wherein determining the availability of the copy includes at least determining a storage location with in storage hierarchy to which the copy belongs.

8. The method of claim 1 wherein determining the availability of the copy includes at least determining one or more access rights associated with the request and identifying the copy as more available if it has a less restrictive access requirement.

9. The method of claim 1 wherein determining the availability of each copy includes at least assigning an availability score to each copy and selecting an identified copy comprises selecting the copy having the greatest score, and wherein the score is based on a type of media on which a copy is stored.

10. The method of claim 1 wherein the request includes a purpose associated with the request and wherein selecting an identified copy includes at least selecting an identified copy based on a timeframe associated with the purpose associated with the request.

11. The method of claim 1 wherein the request is part of a storage operation to be performed on the identified at least one data object and wherein selecting an identified copy comprises selecting a copy on which to perform the storage operation.

12. The method of claim 1 wherein identifying multiple copies of the data object that satisfy the request includes at least identifying older copies for which the identified at least one data object is up to date.

13. The method of claim 1 wherein identifying multiple copies of the data object that satisfy the request includes at least determining one or more access restrictions or privileges of a requester associated with the request and identifying copies that satisfy the one or more access restrictions.

14. The method of claim 1 wherein determining the availability of the copy includes at least retrieving a predetermined availability indication from a database that stores metadata about each of the identified copies, and wherein the method further comprises:

associating with each identified copy one of multiple availability indicators; and

,

updating the metadata of the database with the associated availability indicators.

15. A computer-readable medium containing instructions for controlling a computer system to create copies of data such that a subsequent request can determine the precedence with which to access the copies of data, by a method comprising:

identifying a first copy of source data stored within a computer system;

providing a database with information describing the availability of the first copy of the data stored within the computer system, wherein the availability information describes the effort required to retrieve one or more data objects from the first copy relative to other copies of the source data;

identifying at least a second copy of the source data stored within the computer system;

updating the database with information describing the availability of the second copy of the source data stored within the computer system,

wherein the database is accessible to a client computing device, and wherein the database is configured to permit the client computing device to determine which of multiple copies of source data to access for performing a storage operation based at least in part on the described availability of the first and second copies.

16. The computer-readable medium of claim 15 wherein the availability information comprises at least a type of media on which the copy of the source data is stored.

17. The computer-readable medium of claim 15 wherein the availability information comprises at least a location where the copy of the source data is stored.

18. The computer-readable medium of claim 15 including searching for at least one data object, and displaying multiple copies of the data object and availability of each of the multiple copies compared to each other, to assist a user in determining which of the multiple copies to access.

19. A computer system for managing multiple copies of data, wherein the computer system includes a computing device configured for running applications that generate data objects comprising:

a data management component configured for creating copies of the generated data objects by first creating a first copy of the generated data objects, and then creating one or more secondary copies of the generated data objects;

a data storage component configured to store the first copy of the generated data and the one or more secondary copies of the generated data; and

a data object availability component configured to determine the availability of each copy relative to each of the other copies and to select a copy to use for accessing an identified data object based on the determined relative availability of the copies.

20. The system of claim 19 including a data search component configured to search for at least one data object within the computer system and display multiple copies of the data object and the relative availability of each of the multiple copies such that a user can determine which of the multiple copies to access.