From: Ingo Molnar <mingo@elte.hu>
Subject: Re: Xen & VMI?
Date: Tue, 6 Mar 2007 10:10:06 +0100
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To: Zachary Amsden <zach@vmware.com>
Cc: virtualization <virtualization@lists.osdl.org>, Roland McGrath <roland@redhat.com>, Andrew Morton <akpm@linux-foundation.org>, Linus Torvalds <torvalds@linux-foundation.org>, Jan Beulich <jbeulich@novell.com>, linux-kernel@vger.kernel.org
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* Zachary Amsden <zach@vmware.com> wrote:

> > > reduces the QA effort.  You still have 5 Hypervisors you have to =

> > > test against.
> >
> > yes, just like we have thousands of separate PC boards to support. =

> > But as long as the basic ABI is the same, the QA effort on the Linux =

> > kernel side is alot more focused. (Distros still have =

> > 18446744073709551616 total combinations to QA, and have to make an =

> > educated guess to reduce that to a more manageable number.)
> =

> But hardware PC boards don't do anything as remotely complicate as =

> changing the semantics required for correctness in you MMU =

> implementation. [...]

ugh, PC boards are actually far worse and far more diverse than any =

variances between hypervisors, but i digress.

anyway, my point stands: the Linux kernel is significantly more =

maintainable and easier to QA if it has only a single 'external' =

hypervisor ABI to worry about - and that might as well be VMI. This is a =

really obvious point, i expected the discussion to center more around =

the specifics of such a move ;-)

	Ingo