Pre-warming destination for fast live migration

1. A method, comprising:

identifying, by a source host processor, a destination host as an indication to the source host processor to enter a pre-warm-up phase for live migration of a source virtual machine residing on the source host processor to the destination host;

responsive to the source host processor entering the pre-warm-up phase, copying, by the source host processor, one or more data segments corresponding to a portion of a state of the source virtual machine to the destination host, the one or more data segments corresponding to a portion of memory employed by the source virtual machine; and

receiving a command to migrate the source virtual machine to the destination host after copying the one or more data segments to the destination host.

2. The method of claim 1 , further comprising remaining in the pre-warm-up phase and continuing copying data segments corresponding to the state of the source virtual machine to the destination host when a complete state has been copied to the destination host.

3. The method of claim 1 , further comprising remaining in the pre-warm-up phase and continuing copying data segments corresponding to the state of the source virtual machine to the destination host when a warm-up exit condition has not been attained.

4. The method of claim 1 , further comprising exiting the pre-warm-up phase of migration after a warm-up exit condition has been attained.

5. The method of claim 4 , further comprising:

stopping the source virtual machine;

copying a remaining portion of the state of the source virtual machine to the destination host; and

transmitting a command to the destination host to start a virtual machine corresponding to the copied state of the source virtual machine.

6. The method of claim 4 , further comprising, receiving an indication that a virtual machine corresponding to the copied state of the source virtual machine was successfully started on the destination host.

7. The method of claim 6 , further comprising terminating the source virtual machine.

8. The method of claim 5 , further comprising:

detecting a failure in at least one of copying the state of the source virtual machine to the destination host or starting a virtual machine corresponding to the copied state of the source virtual machine on the destination host;

restarting the source virtual machine; and

copying the state of the source virtual machine to another host machine that is not the destination host.

9. The method of claim 1 , wherein the state of the source virtual machine located on the source host is copied to the destination host from a proxy host separate from the source host and the command to migrate a source virtual machine to the destination host is received from the source host.

10. A method, comprising:

identifying, by a source host processor, a destination host as an indication to the source host processor to enter a pre-warm-up phase for live migration of a source virtual machine to the destination host;

responsive to the source host processor entering the pre-warm-up phase, copying, by the source host processor, one or more data segments corresponding to a portion of a state of the source virtual machine to the destination host, the one or more data segments corresponding to a portion of memory employed by the source virtual machine;

receiving an indication that a warm-up exit condition has been attained when all of the state of the source virtual machine has been transferred to the destination host; and

continuing copying data segments corresponding to the state of the source virtual machine to the destination host.

11. The method of claim 10 , further comprising remaining in the pre-warm-up phase and continuing copying data segments corresponding to the state of the source virtual machine to the destination host when a complete state has been copied to the destination host.

12. The method of claim 10 , further comprising:

receiving a command to migrate the source virtual machine to the destination host and

exiting the pre-warm-up phase of migration after the warm-up exit condition has been attained.

13. The method of claim 12 , further comprising:

stopping the source virtual machine;

copying a remaining portion of the state of the source virtual machine to the destination host; and

transmitting a command to the destination host to start a virtual machine corresponding to the copied state of the source virtual machine.

14. The method of claim 13 , further comprising, receiving an indication that a virtual machine corresponding to the copied state of the source virtual machine was successfully started on the destination host.

15. The method of claim 14 , further comprising terminating the source virtual machine.

16. The method of claim 13 , further comprising:

detecting a failure in at least one of copying the state of the source virtual machine to the destination host or starting a virtual machine corresponding to the copied state of the source virtual machine on the destination host;

restarting the source virtual machine; and

copying the state of the source virtual machine to another host machine that is not the destination host.

17. The method of claim 10 , wherein the state of the source virtual machine located on the source host is copied to the destination host from a proxy host separate from the source host and the command to migrate a source virtual machine to the destination host is received from the source host.

18. A computer system, comprising:

a memory;

a source host processor, coupled to the memory; and

an operating system hosted by the computer system, having access to the memory and use of the source host processor, the operating system to:

identify, by the source host processor, a destination host as an indication to the source host processor to enter a pre-warm-up phase for live migration of a source virtual machine on the source host processor to the destination host;

responsive to the source host processor entering the pre-warm-up phase, copy, by the source host processor, one or more data segments corresponding to a portion of a state of the source virtual machine to the destination host, the one or more data segments corresponding to a portion of memory employed by the source virtual machine;

receive a command to migrate the source virtual machine to the destination host after copying the one or more data segments; and

continue copying data segments corresponding to the state of the source virtual machine to the destination host when a warm-up exit condition has not been attained.

19. A non-transitory computer-readable storage medium including instructions that, when accessed by a processor, cause the processor to perform operations, comprising:

identify, by a source host processor, a destination host as an indication to the source host processor to enter a pre-warm-up phase for live migration of a source virtual machine residing on the source host processor to destination host;

responsive to the source host processor entering the pre-warm-up phase, copy, by the source host processor, one or more data segments corresponding to a portion of the state of the source virtual machine to the destination host, the one or more data segments corresponding to a portion of memory employed by the source virtual machine; and

receive a command to migrate the source virtual machine to the destination host after copying the one or more data segments to the destination host.

20. The non-transitory computer-readable storage medium of claim 19 , further comprising remain in the pre-warm-up phase and continuing copy data segments corresponding to the state of the source virtual machine to the destination host when a warm-up exit condition has not been attained.