Re: VMWARE/ESXi Linux

On 12/3/2024 11:10 AM, Dan Cross wrote:

In article <vina48$3sjr$6@dont-email.me>,
Arne Vajhøj  <arne@vajhoej.dk> wrote:

On 12/3/2024 10:36 AM, Dan Cross wrote:

In article <vin68p$3sjr$4@dont-email.me>,
Arne Vajhøj  <arne@vajhoej.dk> wrote:

KVM runs in Linux not on Linux. Which makes it type 1.

>
Nope.  KVM is dependent on Linux at this point.  The claim that
it is a type-1 hypervisor is predicated on the idea that it was
separable from Linux, but I don't think anyone believes that
anymore.

>
It is the opposite. KVM is type 1 not because it is separable
from Linux but because it is inseparable from Linux.

 Kinda.  The claim is that KVM turns Linux+KVM into a type-1
hypervisor; that is, the entire combination becomes a the HV.
That's sort of a silly distinction, though, since the real
differentiator, defined by Goldberg, is whether or not the VMM
makes use of existing system services, which KVM very much does.

ESXi is basic OS functionality and virtualization services
in a single kernel.
Linux+KVM is basic OS functionality and virtualization services
in a single kernel.
They are logical working the same way.
The differences are not in how they work, but in history
and reusability in other contexts:
* Linux existed before KVM
* Linux has more functionality so it can be and is used without KVM
But type 1 vs type 2 should depend on how it works not on
history and reusability in other contexts.
Arne