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Date: Sun, 21 Mar 2010 21:08:49 +0100
From: Olivier Galibert <galibert@pobox.com>
To: Avi Kivity <avi@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>, Anthony Liguori <anthony@codemonkey.ws>,
       Pekka Enberg <penberg@cs.helsinki.fi>,
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       Gleb Natapov <gleb@redhat.com>, Zachary Amsden <zamsden@redhat.com>,
       ziteng.huang@intel.com, Arnaldo Carvalho de Melo <acme@redhat.com>,
       Fr?d?ric Weisbecker <fweisbec@gmail.com>
Subject: Re: [RFC] Unify KVM kernel-space and user-space code into a single project
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On Sun, Mar 21, 2010 at 10:01:51PM +0200, Avi Kivity wrote:
> On 03/21/2010 09:17 PM, Ingo Molnar wrote:
> >
> >Adding any new daemon to an existing guest is a deployment and usability
> >nightmare.
> >   
> 
> The logical conclusion of that is that everything should be built into 
> the kernel.  Where a failure brings the system down or worse.  Where you 
> have to bear the memory footprint whether you ever use the functionality 
> or not.  Where to update the functionality you need to deploy a new 
> kernel (possibly introducing unrelated bugs) and reboot.
> 
> If userspace daemons are such a deployment and usability nightmare, 
> maybe we should fix that instead.

Which userspace?  Deploying *anything* in the guest can be a
nightmare, including paravirt drivers if you don't have a natively
supported in the OS virtual hardware backoff.  Deploying things in the
host OTOH is business as usual.

And you're smart enough to know that.

  OG.