LIGHTWEIGHT SYNCHRONIZATION OF MIRRORED DISKS

摘要

In a process for migrating a virtual machine's storage from a source disk to a destination disk, during a steady state (i.e., wherein the contents of the virtual machine stored on the source disk and the destination disk are equal), a virtual machine monitor receives a set of write requests from a guest operating system (“guest”) of the virtual machine, provides confirmation of the completion of the set of writes to the source disk, and asynchronously replicates the set of write requests to the destination disk. Upon receipt of a flush request from the guest, the virtual machine monitor confirms completion of the flushing of the destination disk following replication of the write requests to the destination disk. Upon receipt of a switch request from a virtual machine manager, the virtual machine monitor switches the virtual machine to the destination disk and issues subsequent write requests to the destination disk.

主权项

1. A method comprising:
identifying, by the virtual machine monitor, a steady state wherein contents associated with a virtual machine stored on a source disk and a destination disk are equal; receiving a set of write requests comprising data from a guest operating system of the virtual machine; providing confirmation of a completion of the set of writes to the source disk; asynchronously replicating the set of write requests to the destination disk; receiving a flush request from the guest operating system of the virtual machine; providing, to the guest operating system, confirmation of completion of a flush of the destination disk following replication of the set of write requests to the destination disk and writing of the data to persistent storage of the destination disk; receiving a switch request from the virtual machine manager; and switching the virtual machine to the destination disk and issuing subsequent write requests to the destination disk.