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Date: Wed, 9 Sep 2009 15:00:26 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
Message-ID: <20090909120025.GA18473@redhat.com>
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Subject: [Qemu-devel] Re: The State of the SaveVM format
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To: Juan Quintela <quintela@redhat.com>
Cc: qemu-devel@nongnu.org

On Wed, Sep 09, 2009 at 11:26:43AM +0200, Juan Quintela wrote:
> "Michael S. Tsirkin" <mst@redhat.com> wrote:
> > On Wed, Sep 09, 2009 at 10:47:27AM +0200, Juan Quintela wrote:
> >> Notice that there are plans for VMState to do more interesting things
> >> like:
> >> - Be able to show the values in a saved image
> >> - See if a VM is able to load a vmstate (i.e. it has the needed devices
> >>   at the needed versions)
> >> - .....
> >> 
> >> That ones are independent of what we decided for the previous problems.
> >> 
> >> Comments?  Things that I missed for the discussion?
> >> 
> >> Later, Juan.
> >
> > Another idea was to switch to some standard format, like qdev machine
> > description format or xml, so we don't have to maintain our own.
> 
> Are you serious here?  Qemu don't trust the avalavility
> autoconf/automake/gnulib/glib/... and other useful libraries, and now we
> are gonig to require an xml library or qdev machine format (a library
> that don't do releases and is not packaged) for somethnig core of qemu?

I mean the qdev that we have in qemu.  We already know how to
deserialize properties, and need to serialize them to dump machine
description out.


> > All state besides the physical memory dump is normally very
> > small, so this won't have much overhead.
> 
> > This is possible if we give up on backwards compatibility completely.
> 
> If we give up on backwards compatiblity, we fix at least half of the
> problems, independently of swiching to a new format :)
> 
> Later, Juan.