US Patent 9619270 Remote-direct-memory-access-based virtual machine live migration

The current document is directed to methods and systems for moving executing virtual machines between host systems in a virtual data center. In described implementations, remote-direct memory access is used for transferring memory contents and, in certain implementations, additional data between the host systems to facilitate live migration of virtual machines. To provide increased efficiency, transfer of the contents of a shared memory page from a source host system to target host system during migration of a virtual machine is deferred until the relocated virtual machine attempts to write to the shared memory page.