Re:A reimplementation of NetBSD using a Microkernel [video]
by JoshTriplett on Wednesday June 17, 2015 @09:39PM
(#9736293)
> Xen allows full OSes to be guests and run on top of it. Microkernels only allow servers to run on top of it, and those servers have to be purpose-written and cannot meaningfully be ported.
L4 is an archetypal microkernel, and people often run full OSes or other ported software under it, including Linux.
> Xen doesn't provide hardware abstraction and is fully invisible (except to the extent it advertises itself); microkernels are neither.
Microkernels typically don't abstract any hardware other than CPU and memory; any other drivers would run under the microkernel.
And Xen is only "invisible" if you run full hardware virtualization and no paravirtualized drivers.
> Paravirtualization (what you did before VT-x and similar)
People still use "paravirtualization" today; see the "virtio" drivers typically used with KVM.
L4 is an archetypal microkernel, and people often run full OSes or other ported software under it, including Linux.
> Xen doesn't provide hardware abstraction and is fully invisible (except to the extent it advertises itself); microkernels are neither.
Microkernels typically don't abstract any hardware other than CPU and memory; any other drivers would run under the microkernel.
And Xen is only "invisible" if you run full hardware virtualization and no paravirtualized drivers.
> Paravirtualization (what you did before VT-x and similar)
People still use "paravirtualization" today; see the "virtio" drivers typically used with KVM.