On Fri, Sep 07, 2018 at 04:26:50PM +0200, Martin Kletzander wrote: > On Thu, Sep 06, 2018 at 10:04:35AM -0400, Cole Robinson wrote: > > On 09/06/2018 09:04 AM, Martin Kletzander wrote: > > > On Wed, Sep 05, 2018 at 03:37:22PM +0100, Daniel P. Berrangé wrote: > > > > On Wed, Sep 05, 2018 at 02:01:42PM +0200, Martin Kletzander wrote: > > > > > On Wed, Sep 05, 2018 at 09:28:52AM +0100, Daniel P. Berrangé wrote: > > > > > > On Tue, Sep 04, 2018 at 03:44:12PM -0400, Cole Robinson wrote: > > > > > > > Right now in virt-manager we only track a VM's OS name (win10, > > > > > fedora28, > > > > > > > etc.) during the VM install phase. This piece of data is important > > > > > > > post-install though: if the user adds a new disk to the VM later, > > > > > we want to > > > > > > > be able to ask libosinfo about what devices the installed OS > > > > > supports, so we > > > > > > > can set optimal defaults, like enabling virtio. > > > > > > > > > > > > > > There isn't any standard libvirt XML field to track this kind of > > > > > info > > > > > > > though, so apps have to invent their own schema. nova and rhev do it > > > > > > > indirectly AFAICT. gnome-boxes does it directly with XML like this: > > > > > > > > > > > > > > <metadata> > > > > > > > <boxes:gnome-boxes > > > > > xmlns:boxes="https://wiki.gnome.org/Apps/Boxes";> > > > > > > > <os-id>http://fedoraproject.org/fedora/28</os-id> > > > > > > > .... > > > > > > > </boxes:gnome-boxes> > > > > > > > </metadata> > > > > > > > > > > > > > > I want to add something similar to virt-manager but it seems a > > > > > shame to > > > > > > > invent our own private schema for something that most non-trivial > > > > > virt apps > > > > > > > will want to know about. I was thinking a schema we could > > > > > document with > > > > > > > libosinfo, something like > > > > > > > > > > > > > > <metadata> > > > > > > > <libosinfo > > > > > > > xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0";> > > > > > > > <os-id>http://fedoraproject.org/fedora/28</os-id> > > > > > > > </libosinfo> > > > > > > > </metadata> > > > > > > > > > > > > Yes, I would like to see this standardized under <matadata>. > > > > > > > > > > > > > > > > Me too and what Cole suggested looks fine. > > > > > > > > It occurs to me that we actually need more than just the os-id value. > > > > > > > > When you query devices for a given OS, you'll often be told that multiple > > > > devices are compatible, and the mgmt app can decide which of them to then > > > > use. > > > > > > > > So if we want consistency when later hotplugging, we should make a record > > > > of which devices we decided to use too, so if the mgmt app changes its > > > > preference, we still know what we originally picked. > > > > > > > > eg to express that we use virtio-net and virtio-blk (even if virtio-scsi > > > > was supported by the OS): > > > > > > > > <metadata> > > > > <libosinfo > > > > xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0";> > > > > <os id="http://fedoraproject.org/fedora/28"/> > > > > <device id="http://pcisig.com/pci/1af4/1000"/> > > > > <device id="http://pcisig.com/pci/1af4/1001"/> > > > > </libosinfo> > > > > </metadata> > > > > > > > > Note, I'm suggesting using an 'id' attribute, rather than naming the > > > > element 'os-id', to be more closely aligned with osinfo schema. > > > > > > > > > > I'm not against that <device id =''/> but it is going to take some > > > effort to > > > properly specify what is really meant by that. The fact that some > > > device model > > > was chosen for a particular device does not necessarily mean that it is > > > requested as the default. It only means what is actually encoded in the > > > XML > > > already, that is a particular model for a particular device. > > > > > > > Yeah I'm a bit confused by this as well, it's not exactly clear to me > > how we would use or set XML like that for virt-manager, and how other > > apps would be expected to consume it. > > > > That's what I though of when trying to say we need to define the meaning of > that. What might be meaningful is if the user selects a particular *default* > model for new devices (e.g. disks should be IDE by default) then that option > could be honoured when adding a new device of that type (unless requested > otherwise). I'm not sure if that's what Daniel meant by that. Consider libosinfo reports that the guest supports virtio-blk, and virtio-scsi. The mgmt apps decides to use virtio-blk for disks. We should remember that so that when we later add more disks, we default to also using virtio-blk unless the user really wants virtio-scsi instead. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| _______________________________________________ Libosinfo mailing list Libosinfo@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libosinfo
