Virtio device tuning
In the virtualization world, a comparison is always made with bare-metal systems. Paravirtualized drivers enhance the performance of guests and try to retain near-bare-metal performance. It is recommended to use paravirtualized drivers for fully virtualized guests, especially when the guest is running with I/O-heavy tasks and applications. Virtio is an API for virtual IO and was developed by Rusty Russell in support of his own virtualization solution, called
lguest. Virtio was introduced to achieve a common framework for hypervisors for IO virtualization.
In short, when we use paravirtualized drivers, the VM OS knows that there's a hypervisor beneath it, and therefore uses frontend drivers to access it. The frontend drivers are part of the guest system. When there are emulated devices and someone wants to implement backend drivers for these devices, hypervisors do this job. The frontend and backend drivers communicate through a virtio-based path. Virtio...