Patent ID: 8689211

Claim:
A method of migrating a virtual machine (VM) in a computing environment, the method comprising: receiving a request to migrate a VM executing on a source host to a destination host; defining a recovery point to which the VM is restored during recovery from a fault; and iteratively copying pages in memory of the source host associated with the VM to the destination host, wherein the iterative copying comprises maintaining a record of pages in the memory that have been copied to the destination host, wherein a page in the memory is associated with a first flag to indicate that the page has not been copied to the destination host or has been modified subsequent to being copied to the destination host, wherein a page in the memory is associated with a second flag to indicate that the page is permitted to be written to, wherein a page in the memory is associated with a third flag to indicate that an original state of the page has not been preserved, wherein if a write operation is directed to a first page associated with the first flag and the third flag, an original state of the first page is preserved and the association between the first page and the third flag is terminated, wherein if a write operation is directed to a first page associated with the second flag, the association between the first page and the second flag is terminated and the first page is associated with the first flag, and if the first page is associated with the third flag, an original state of the first page is preserved and the association between the first page and the third flag is terminated.