MANAGING VIRTUAL-MACHINE IMAGE CLONING

• US 20190310775A1
• Filed: 04/09/2018
• Published: 10/10/2019
• Est. Priority Date: 04/09/2018
• Status: Active Grant

• Current Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Original Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Inventors: Chen, Huamin, Litke, Adam Gerard, Deutsch, Fabian
• Granted Patent: US 11,074,001 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 2009/45562 Creating, deleting, cloning virtual machine instances
• CPC Class Codes: G06F 2009/45575 Starting, stopping, suspending or resuming virtual machine instances
• CPC Class Codes: G06F 2009/45583 Memory management, e.g. access or allocation
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/0683 Plurality of storage devices
• CPC Class Codes: G06F 8/60 Software deployment
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects

Abstract

Cloning of virtual-machine images can be managed. For example, a computing device can copy a segment of a virtual-machine image stored in a second storage device to a first storage device in response to receiving a first read request for the segment from a virtual machine. The first storage device may be capable of responding to read requests from the virtual machine with less latency than the second storage device. The computing device can also update a log to indicate that the segment is stored on the first storage device. Thereafter, the computing device can receive a second read request for the segment. In response, the computing device can determine that the segment is stored in the first storage device using the log, and provide the segment by obtaining the segment from the first storage device.

Claims

1. A system comprising:

a processing device; and

a memory device including instructions that are executable by the processing device for causing the processing device to;

copy a segment of a virtual-machine image stored in a second storage device to a first storage device in response to receiving a first read request for the segment from a virtual machine that is deployable using the virtual-machine image, the first storage device being capable of responding to read requests from the virtual machine with less latency than the second storage device;

update a log to indicate that the segment of the virtual-machine image is stored on the first storage device; and

in response to receiving a second read request for the segment from the virtual machine subsequent to receiving the first read request;

determine that the segment is stored in the first storage device using the log; and

based on determining that the segment is stored in the first storage device, provide the segment to the virtual machine by obtaining the segment from the first storage device.

2. The system of claim 1, wherein the instructions are for a device driver configured to interface between the virtual machine and the first storage device.

3. The system of claim 1, wherein the first storage device is a first type of storage device and the second storage device is a second type of storage device that is different from the first type of storage device.

4. The system of claim 3, wherein the first storage device is a block storage device and the second storage device is an object storage device.

5. The system of claim 1, wherein the memory device further comprises instructions that are executable by the processing device for causing the processing device to copy the segment from the second storage device to the first storage device in response to the first read request by:

determining that the segment is not stored in the first storage device by accessing the log indicating which portions of the virtual-machine image are stored in the first storage device; and

in response to determining that the segment is not stored in the first storage device;

obtaining the segment from the second storage device;

storing the segment in the first storage device to enable a subsequent read request for the segment to be fulfilled using the first storage device; and

providing the segment to the virtual machine in a read response to the first read request.

6. The system of claim 5, wherein the first read request is in a first format configured for the first storage device, and wherein the memory device further comprises instructions that are executable by the processing device for causing the processing device to:

obtain the segment from the second storage device by translating at least a portion of the first read request into a second format that is different from the first format, the second format being configured for obtaining the segment from the second storage device.

7. The system of claim 1, wherein the memory device further comprises instructions that are executable by the processing device for causing the processing device to, prior to copying the segment of the virtual-machine image from the second storage device to the first storage device:

create a partition in the first storage device for storing the log; and

generate the log within the partition.

8. The system of claim 1, wherein the memory device further comprises instructions that are executable by the processing device for causing the processing device to:

receive a write command from the virtual machine, the write command being for storing data in the first storage device;

determine that a prior version of the data does not exist in the first storage device using the log; and

in response to determining that the prior version of the data does not exist in the first storage device;

obtain the prior version of the data from the second storage device;

overwrite a portion of the prior version of the data with new data indicated in the write command, thereby forming an updated version of the data;

store the updated version of the data in the first storage device; and

update the log to indicate that the data is stored in the first storage device.

9. The system of claim 1, wherein the virtual machine comprises a first virtual machine and a second virtual machine, and wherein the first read request is from the first virtual machine and the second read request is from the second virtual machine.

10. A method comprising:

copying, by a processing device, a segment of a virtual-machine image stored in a second storage device to a first storage device in response to receiving a first read request for the segment from a virtual machine that is deployable using the virtual-machine image, the first storage device being capable of responding to read requests from the virtual machine with less latency than the second storage device;

updating, by the processing device, a log to indicate that the segment of the virtual-machine image is stored on the first storage device; and

in response to receiving a second read request for the segment from the virtual machine subsequent to receiving the first read request;

determining, by the processing device, that the segment is stored in the first storage device using the log; and

based on determining that the segment is stored in the first storage device, providing, by the processing device, the segment to the virtual machine by obtaining the segment from the first storage device.

11. The method of claim 10, wherein the first storage device is a block storage device and the second storage device is an object storage device.

12. The method of claim 10, further comprising copying the segment from the second storage device to the first storage device in response to the first read request by:

determining that the segment is not stored in the first storage device by accessing the log indicating which portions of the virtual-machine image are stored in the first storage device; and

in response to determining that the segment is not stored in the first storage device;

obtaining the segment from the second storage device;

storing the segment in the first storage device to enable a subsequent read request for the segment to be fulfilled using the first storage device; and

providing the segment to the virtual machine in a read response to the first read request.

13. The method of claim 10, wherein the first read request is in a first format configured for the first storage device, further comprising:

obtaining the segment from the second storage device by translating at least a portion of the first read request into a second format that is different from the first format, the second format being configured for obtaining the segment from the second storage device.

14. The method of claim 10, further comprising:

receiving a write command from the virtual machine, the write command being for storing data in the first storage device;

determining that a prior version of the data does not exist in the first storage device using the log; and

in response to determining that the prior version of the data does not exist in the first storage device;

obtaining the prior version of the data from the second storage device;

overwriting a portion of the prior version of the data with new data indicated in the write command, thereby forming an updated version of the data;

storing the updated version of the data in the first storage device; and

updating the log to indicate that the data is stored in the first storage device.

15. The method of claim 10, wherein the virtual machine comprises a first virtual machine and a second virtual machine, and wherein the first read request is from the first virtual machine and the second read request is from the second virtual machine.

16. A non-transitory computer-readable medium comprising program code that is executable by a processing device for causing the processing device to:

copy a segment of a virtual-machine image stored in a second storage device to a first storage device in response to receiving a first read request for the segment from a virtual machine that is deployable using the virtual-machine image, the first storage device being capable of responding to read requests from the virtual machine with less latency than the second storage device;

update a log to indicate that the segment of the virtual-machine image is stored on the first storage device; and

in response to receiving a second read request for the segment from the virtual machine subsequent to receiving the first read request;

determine that the segment is stored in the first storage device using the log; and

based on determining that the segment is stored in the first storage device, provide the segment to the virtual machine by obtaining the segment from the first storage device.

17. The non-transitory computer-readable medium of claim 16, wherein the first storage device is a block storage device and the second storage device is an object storage device.

18. The non-transitory computer-readable medium of claim 16, further comprising program code that is executable by the processing device for causing the processing device to copy the segment from the second storage device to the first storage device in response to the first read request by:

determining that the segment is not stored in the first storage device by accessing the log indicating which portions of the virtual-machine image are stored in the first storage device; and

in response to determining that the segment is not stored in the first storage device;

obtaining the segment from the second storage device;

storing the segment in the first storage device to enable a subsequent read request for the segment to be fulfilled using the first storage device; and

providing the segment to the virtual machine in a read response to the first read request.

19. The non-transitory computer-readable medium of claim 16, wherein the first read request is in a first format configured for the first storage device, further comprising program code that is executable by the processing device for causing the processing device to:

obtain the segment from the second storage device by translating at least a portion of the first read request into a second format that is different from the first format, the second format being configured for obtaining the segment from the second storage device.

20. The non-transitory computer-readable medium of claim 16, further comprising program code that is executable by the processing device for causing the processing device to:

receive a write command from the virtual machine, the write command being for storing data in the first storage device;

determine that a prior version of the data does not exist in the first storage device using the log; and

in response to determining that the prior version of the data does not exist in the first storage device;

obtain the prior version of the data from the second storage device;

overwrite a portion of the prior version of the data with new data indicated in the write command, thereby forming an updated version of the data;

store the updated version of the data in the first storage device; and

update the log to indicate that the data is stored in the first storage device.