what is virtualbox paravirtualization interface

Yet, type-2 hypervisors, such as VirtualBox, benefit from the continual advancement of their underlying OS. Type-1 hypervisors have an inherent advantage over type-2 regarding performance.

In contrast, XEN is a type-1 hypervisor which runs directly on top of the bare-metal hardware.

VirtualBox, like KVM, is a type-2 hypervisor, meaning that it runs as a process on the host OS (Linux). Subsequently, VirtualBox was rebranded as Oracle VM VirtualBox, but the software has remained free and open-source. In 2010, Oracle acquired Sun Microsystems and, as a result, took over the ownership of several open-source technologies including VirtualBox and mySQL. Parts 2, 3, and 4 cover, respectively, additional post-installation tasks, how to access USB flash drives on the guest OS, and how to share folders between host and guest. As part 1 of a 4-part series, this post outlines how to 1) install VirtualBox on Debian 10 (buster), and 2) build a FreeBSD virtual machine. Notable open-source software include VirtualBox, KVM, and Xen. Many virtualization software (aka hypervisors) can run on the host operating system of Linux.

What is virtualbox paravirtualization interface