摘要 |
A method, apparatus and system are described for seamlessly sharing I/O devices amongst multiple virtual machines ("VMs") on a host computer. Specifically, according to one embodiment of the invention, the virtual machine manager ("VMM") on the host cycles access to the I/O devices amongst the VMs according to a round robin or other such allocation scheme. In order to provide direct access to the devices, the VMM may save the device state pertaining to the currently active VM, store the state in a memory region allocated to the currently active VM, retrieve a device state for a new VM from its memory region and restore the device using the retrieved device state, thus providing the illusion that each VM has direct, full-speed, exclusive access to the I/O device.
|