Live migration Backend process

In a live migration, the guest virtual machine continues to run on the source host physical machine while its memory pages are transferred, in order, to the destination host physical machine. During migration,KVM monitors the source for any changes in pages it has already transferred, and begins to transfer
these changes when all of the initial pages have been transferred. KVM also estimates transfer speed during migration, so when the remaining amount of data to transfer will take a certain configurable period of time (10ms by default), KVM suspends the original guest virtual machine, transfers the remaining
data, and resumes the same guest virtual machine on the destination host physical machine.

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