A virtual disk and associated methods for facilitating live migration of virtual machines in distributed computing systems are disclosed herein. In one embodiment, a method includes during a live migration of a virtual machine, determining whether a destination virtual disk on a node contains a block of data corresponding to the migrated virtual machine. The method can also include, in response to determining that the destination virtual disk does not contain the block of data, retrieving the block of data from a source virtual disk of the migrated virtual machine, writing the retrieved block of data to one or more empty sectors on the destination virtual disk, and marking the one or more written to sectors containing the block of data as read-only on the destination virtual disk.