Background Migration of Virtual Storage

摘要

Described is a technology by which a virtual hard disk is migrated from a source storage location to a target storage location without needing any shared physical storage, in which a machine may continue to use the virtual hard disk during migration. This facilitates use the virtual hard disk in conjunction with live-migrating a virtual machine. Virtual hard disk migration may occur fully before or after the virtual machine is migrated to the target host, or partially before and partially after virtual machine migration. Background copying, sending of write-through data, and/or servicing read requests may be used in the migration. Also described is throttling data writes and/or data communication to manage the migration of the virtual hard disk.

主权项

1. One or more computer storage devices having computer-executable instructions, which when executed by a computer, cause the computer to perform steps comprising:
controlling migration of a virtual storage extent from a source storage location to a target storage location; and servicing read requests against data located in the virtual storage extent during the migration, including determining whether read data corresponding to the read request has already been migrated to the target storage location, and if so, using the read data that has already been migrated to the target storage location, and if not, obtaining the read data from the source storage location or another location accessible to the target storage location.