Non-disruptive realignment of virtual data

• US 8,819,383 B1
• Filed: 02/17/2012
• Issued: 08/26/2014
• Est. Priority Date: 02/17/2012
• Status: Active Grant

• Current Assignee: NetApp, Inc.
• Original Assignee: NetApp, Inc.
• Inventors: Tucker, Andrew, Forgette, Eric Paul, Gupta, Mohit, Jobanputra, Varun, Periyagaram, Subramaniam V., Mathew, Jose, Shivappa, Vishwajith, Shekhar, Sisir
• Primary Examiner(s): BATAILLE, PIERRE MICHE
• Application Number:
  US13/399,213
• Time in Patent Office: 921 Days
• Field of Search: 711/154, 711/201, 711/202, 711/E12.001
• US Class Current: 711/201
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0613 in relation to throughput
• CPC Class Codes: G06F 3/0638 Organizing or formatting or addressing of data
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

One or more techniques and/or systems are provided for non-disruptively addressing misalignment between a virtual data format and an underlying data format. Virtual data, such as a guest operating system of a virtual machine, may be stored within a virtual structure, such as a virtual machine disk, according to a virtual data format. The virtual structure may be stored within a storage device according to a storage data format. If misalignment is detected, then a new data container may be created within the storage device. A shim, sized according to a misalignment offset, may be inserted into the new data container in order to align the new data container with the storage device. Virtual data may be migrated from the virtual structure to the new data container to achieve alignment. During the migration, the virtual data may remain available from the virtual structure (e.g., a virtual machine may still execute).

Claims

1. A method for non-disruptively addressing misalignment between a virtual data format and a storage data format within a virtualized storage environment, comprising:

comparing a virtual data format associated with a manner with which virtual data is stored within a virtual structure and a storage data format associated with a manner with which data is stored within a storage device to determine a misalignment offset;

creating a new data container within the storage device;

inserting a shim, sized according to the misalignment offset, into a starting location of the new data container; and

migrating virtual data within the virtual structure to the new data container, the migrating comprising adjusting I/O offsets of virtual data according to the shim, the migrating comprising maintaining availability of the virtual data within the virtual structure during the migration.

2. The method of claim 1, the shim comprising padding that is sized according to the misalignment offset.

3. The method of claim 1, the new data container comprising a new data volume.

4. The method of claim 1, comprising:

querying metadata within the virtual structure to determine the virtual data format, the virtual data format comprising a virtual block size and a virtual offset of the virtual structure.

5. The method of claim 1, comprising:

querying storage configuration data associated with the storage device to determine the storage data format, the storage data format comprising a storage block size and a storage offset of the storage device.

6. The method of claim 4, the comparing comprising:

comparing the virtual block size and the virtual offset of the virtual data format with a storage block size and a storage offset of the storage data format to determine the misalignment offset.

7. The method of claim 4, the metadata comprising at least one of:

a master boot record;

a global unique ID (GUID) partition table;

or

a range of bytes comprised within a metadata table that is associated with the virtual structure.

8. The method of claim 1, the virtual structure comprising at least one of virtual machine data, a virtual disk, or a logical unit number (LUN).

9. The method of claim 1, the migrating comprising:

migrating the virtual data to the new data container while a guest operating system of a virtual machine stored within the virtual data is executing from the virtual structure.

10. The method of claim 1, the migrating comprising:

migrating the virtual data to the new data container without interrupting access to a guest operating system of a virtual machine stored within the virtual data.

11. The method of claim 1, comprising:

satisfying an I/O request for requested virtual data using the virtual data within the new data container comprising the shim.

12. The method of claim 11, the satisfying comprising:

modifying a target location specified within the I/O request based upon an adjusted I/O offset to identify the requested virtual data.

13. The method of claim 1, comprising:

identifying an I/O request for requested virtual data as originating from a logical application; and

sending a response to the logical application, the response comprising shim information and the requested virtual data obtained from the new data container.

14. The method of claim 13, comprising:

instructing the logical application to provide the shim information to a destination location within which the requested virtual data is to be stored.

15. The method of claim 14, the requested virtual data stored within the destination location using an adjusted I/O offset derived from the shim information.

16. A method for propagating shimmed virtual data from a source location to a destination location within a virtualized storage environment, comprising:

sending, from a logical application, a first I/O request to a source location for requested virtual data stored as shimmed virtual data within a new data container of a storage device;

receiving a response comprising shim information about the shim and shimmed virtual data as the requested virtual data, the shim information comprising an adjusted I/O offset of the shimmed virtual data used to offset misalignment between a virtual data format associated with a manner with which virtual data is stored within a misaligned virtual structure and a storage data format associated with a manner with which data is stored within the storage device; and

sending, from the logical application, a second I/O request to a destination location, the second I/O request comprising the requested virtual data and the shim information, the shim information used to store the requested virtual data using the adjusted I/O offset within the destination location.

17. A system for non-disruptively addressing misalignment between a virtual data format and a storage data format within a virtualized storage environment, comprising:

a misalignment detection component configured to;

compare a virtual data format associated with a manner with which virtual data is stored within a virtual structure and a storage data format associated with a manner with which data is stored within a storage device to determine a misalignment offset; and

an alignment component configured to;

create a new data container within the storage device;

insert a shim, sized according to the misalignment offset, into a starting location of the new data container;

migrate virtual data within the virtual structure to the new data container as shimmed virtual data, the migrating comprising adjusting I/O offsets of shimmed virtual data according to the shim; and

maintain availability of the virtual data within the virtual structure during the migration.

18. The system of claim 17, the shim comprising padding sized according to the misalignment offset.

19. The system of claim 17, the new data container comprising a new data volume.

20. The system of claim 17, the alignment component configured to:

migrate the virtual data to the new data container without interrupting access to a guest operating system of a virtual machine stored within the virtual data.

21. The system of claim 17, the alignment component configured to:

satisfy an I/O request for requested virtual data using the shimmed virtual data within the new data container.

22. The system of claim 21, the alignment component configured to:

modify a target location specified within the I/O request based upon an adjusted I/O offset to identify the shimmed virtual data.

23. The system of claim 17, the alignment component configured to:

identify an I/O request for requested virtual data as originating from a logical application; and

send a response to the logical application, the response comprising shim information and the shimmed virtual data obtained from the new data container.

24. The system of claim 23, the alignment component configured to:

instruct the logical application to provide the shim information to a destination location within which the requested virtual data is to be stored.

25. The system of claim 24, the requested virtual data stored within the destination location using an adjusted I/O offset derived from the shim information.

26. A system for propagating shimmed virtual data from a source location to a destination location within a virtualized storage environment, comprising:

a logical replication component configured to;

send, from a logical application, a first I/O request to a source location for requested virtual data stored as shimmed virtual data within a new data container of a storage device;

receive a response comprising shim information and shimmed virtual data as the requested virtual data, the shim information comprising an adjusted I/O offset of the shimmed virtual data used to offset misalignment between a virtual data format associated with a manner with which virtual data is stored within a misaligned virtual structure and a storage data format associated with a manner with which data is stored within the storage device; and

send, from the logical application, a second I/O request to a destination location, the second I/O request comprising the requested virtual data and the shim information, the shim information used to store the requested virtual data using the adjusted I/O offset within the destination location.

27. A non-transitory computer readable medium comprising instructions which when executed perform a method for non-disruptively addressing misalignment between a virtual data format and a storage data format within a virtualized storage environment, comprising:

comparing a virtual data format associated with a manner with which virtual data is stored within a virtual structure and a storage data format associated with a manner with which data is stored within a storage device to determine a misalignment offset;

creating a new data container within the storage device;

inserting a shim, sized according to the misalignment offset, into a starting location of the new data container; and

migrating virtual data within the virtual structure to the new data container, the migrating comprising adjusting one or more I/O offsets of virtual data according to the shim, the migrating comprising maintaining availability of the virtual data within the virtual structure during the migration.