Lightweight synchronization of mirrored disks

A non-transitory computer readable storage medium including instructions that, when executed by a processing device, cause the processing device to perform operations comprising:

• identifying, by a virtual machine monitor executed by the processing device, a steady state wherein contents associated with a virtual machine stored on a source disk and a destination disk are equal;
• receiving, by the virtual machine monitor, 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 a virtual machine manager;
• and
• switching the virtual machine to the destination disk and issuing subsequent write requests to the destination disk.

A system comprising:

• a memory;
• a processing device, coupled to the memory, the processing device to perform operations 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.