Importing and exporting virtual disk images

• US 10,599,457 B2
• Filed: 02/25/2014
• Issued: 03/24/2020
• Est. Priority Date: 02/25/2014
• Status: Active Grant

• Current Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Original Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Inventors: Simoncelli, Federico
• Primary Examiner(s): Williams, Clayton R
• Assistant Examiner(s): Robinson, Christopher B
• Application Number:
  US14/189,783
• Publication Number:
  US 20150244802A1
• Time in Patent Office: 2,219 Days
• Field of Search: None
• CPC Class Codes: G06F 2009/4557 Distribution of virtual machine instances; Migration and load balancing
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects

Abstract

A processing device receives a first command to export a first virtual image to a server, wherein the first virtual disk image comprises a plurality of volumes that comprise a read-only base volume and at least one additional volume that comprises changes to the base volume. The processing device generates a map of the first virtual disk image, wherein the map identifies, for each offset in the first virtual disk image, which of the plurality of volumes contains most recent data for the offset. The processing device uses the map to read data at offsets of the virtual disk image from the plurality of volumes. The processing device transmits the data to the server.

Claims

1. A method comprising:

receiving, by a processing device, a first command to export a first virtual disk image to a server, wherein the first virtual disk image comprises a plurality of volumes that comprise a read-only base volume and at least one additional volume that comprises changes to the base volume;

generating, by the processing device, an area for the first virtual disk image;

receiving a map of the first virtual disk image that identifies offsets of the first virtual disk image and, for each of the offsets, a particular volume of the plurality of volumes that comprises data for the offset, and wherein each of the offsets corresponds to a different portion of the first virtual disk image and the map identifies the particular volume for each offset that comprises most recent data for the different portion of the first virtual disk image;

writing, by the processing device, data for the offsets of the first virtual disk image that has been read from the particular volumes of the plurality of volumes of the first virtual disk image to the area to consolidate the plurality of volumes of the first virtual disk image into a single volume of the first virtual disk image, and wherein the single volume is converted to a different disk format than the plurality of volumes of the first virtual disk image, and wherein the different disk format is associated with a different virtual size relative to a size of the first virtual disk image than the plurality of volumes of the first virtual disk; and

transmitting, by the processing device, the data of the single volume of the first virtual disk image comprising data read from the particular volumes of the plurality of volumes to the server.

2. The method of claim 1, wherein the area is generated in a buffer, the method further comprising:

compressing the data in the area responsive to an amount of data in the buffer reaching a threshold;

wherein transmitting the data to the server comprises streaming the compressed data to the server.

3. The method of claim 1, wherein the server comprises a hypertext transport protocol (HTTP) server.

4. The method of claim 1, wherein the at least one additional volume comprises a read-write volume that is a snapshot of at least one of the base volume or of another volume.

5. The method of claim 1, wherein the offsets are read in ascending order from a first to a last offset, and wherein the data for at least a portion of the offsets is transmitted prior to the data for all of the offsets being read.

6. The method of claim 1, further comprising:

receiving a second command to import a second virtual disk image from the server;

retrieving metadata of the second virtual disk image from the server;

creating a new volume for the second virtual disk image;

downloading data for the second virtual disk image; and

inserting the data for the second virtual disk image into the new volume.

7. The method of claim 6, wherein the second virtual disk image has an image size that corresponds to a file size of the second virtual disk image and a virtual size that corresponds to a disk size that is read by guest software that runs in the second virtual machine, the method further comprising:

downloading a specific portion of the virtual disk image that comprises a header;

reading the header in the specific portion of the virtual disk image to determine the virtual size; and

using the virtual size and the image size for the new volume.

8. A non-transitory computer readable storage medium having instructions that, when executed by a processing device, cause the processing device to:

receive, by the processing device, a first command to export a first virtual disk image to a server, wherein the first virtual disk image comprises a plurality of volumes that comprise a read-only base volume and at least one additional volume that comprises changes to the base volume;

generate, by the processing device, an area for the first virtual disk image;

receive a map of the first virtual disk image that identifies offsets of the first virtual disk image and, for each of the offsets, a particular volume of the plurality of volumes that comprises data for the offset;

write, by the processing device, data for the offsets of the first virtual disk image that has been read from the particular volumes of the plurality of volumes of the first virtual disk image to the area to consolidate the plurality of volumes of the first virtual disk image into a single volume of the first virtual disk image, and wherein each of the offsets corresponds to a different portion of the first virtual disk image and the map identifies the particular volume for each offset that comprises most recent data for the different portion of the first virtual disk image, and wherein the single volume is converted to a different disk format than the plurality of volumes of the first virtual disk image, and wherein the different disk format is associated with a different virtual size relative to a size of the first virtual disk image than the plurality of volumes of the first virtual disk; and

transmit, by the processing device, the data of the single volume of the first virtual disk image comprising data read from the particular volumes of the plurality of volumes to the server.

9. The non-transitory computer readable storage medium of claim 8, wherein the area is generated in a buffer, the processing device is further to:

compress the data in the area responsive to an amount of data in the buffer reaching a threshold, wherein to transmit the data to the server, the processing device is further to stream the compressed data to the server.

10. The non-transitory computer readable storage medium of claim 8, wherein the server comprises a hypertext transport protocol (HTTP) server.

11. The non-transitory computer readable storage medium of claim 8, wherein the at least one additional volume comprises a read-write volume that is a snapshot of at least one of the base volume or of another volume.

12. The non-transitory computer readable storage medium of claim 8, wherein the offsets are read in ascending order from a first to a last offset, and wherein the data for at least a portion of the offsets is transmitted prior to the data for all of the offsets being read.

13. The non-transitory computer readable storage medium of claim 8, the processing device further to:

receive a second command to import a second virtual disk image from the server;

retrieve metadata of the second virtual disk image from the server;

create a new volume for the second virtual disk image;

download data for the second virtual disk image; and

insert the data for the second virtual disk image into the new volume.

14. The non-transitory computer readable storage medium of claim 13, wherein the second virtual disk image has an image size that corresponds to a file size of the second virtual disk image and a virtual size that corresponds to a disk size that is read by guest software that runs in the second virtual machine, the processing device further to:

download a specific portion of the virtual disk image that comprises a header;

read the header in the specific portion of the virtual disk image to determine the virtual size; and

use the virtual size and the image size for the new volume.

15. A computing device comprising:

a memory to store a first virtual disk image; and

a processing device, operatively coupled to the memory, wherein the processing device is to;

receive a first command to export the first virtual disk image to a server, wherein the first virtual disk image comprises a plurality of volumes that comprise a read-only base volume and at least one additional volume that comprises changes to the base volume;

generate an area for the first virtual disk image in a buffer;

receive a map of the first virtual disk image that identifies offsets of the first virtual disk image and, for each of the offsets, a particular volume of the plurality of volumes that comprises data for the offset;

write data for the offsets of the first virtual disk image that has been read from particular volumes of the plurality of volumes of the first virtual disk image to the area in the buffer to consolidate the plurality of volumes of the first virtual disk image into a single volume of the first virtual disk image, and wherein each of the offsets corresponds to a different portion of the first virtual disk image and the map identifies the particular volume for each offset that comprises most recent data for the different portion of the first virtual disk image, and wherein the single volume is converted to a different disk format than the plurality of volumes of the first virtual disk image, and wherein the different disk format is associated with a different virtual size relative to a size of the first virtual disk image than the plurality of volumes of the first virtual disk;

compress the data of the single volume of the first virtual disk image in the area in the buffer; and

stream the compressed data of the single volume of the first virtual disk image comprising data read from the particular volumes of the plurality of volumes to the server.

16. The computing device of claim 15, wherein the processing device is further to:

receive a second command to import a second virtual disk image from the server;

retrieve metadata of the second virtual disk image from the server;

create a new volume for the second virtual disk image;

download data for the second virtual disk image; and

insert the data for the second virtual disk image into the new volume.

17. The computing device of claim 16, wherein the second virtual disk image has an image size that corresponds to a file size of the second virtual disk image and a virtual size that corresponds to a disk size that is read by guest software that runs in the second virtual machine, and wherein the processing device is further to:

download a specific portion of the virtual disk image that comprises a header;

read the header in the specific portion of the virtual disk image to determine the virtual size; and

use the virtual size and the image size for the new volume.