[libvirt] Re: [PATCH/RFC] kvm/qemu vs libvirtd restarts

Guido Günther agx at sigxcpu.org
Sun Nov 30 11:43:48 UTC 2008

On Wed, Nov 26, 2008 at 08:54:40PM +0000, Daniel P. Berrange wrote:
> Hmm, interesting idea - we already have a variant for parsing based
> off an arbitrary XML node, rather than assuming the root, 
>   virDomainDefPtr virDomainDefParseNode(virConnectPtr conn,
>                                         virCapsPtr caps,
>                                         xmlDocPtr doc,
>                                         xmlNodePtr root);
> So we could add a wrapper function which writes out a XML doc
>    <domstate state="running" pid="1234">
>      <monitor path="/dev/pts/4">
>      <domain id='32'>
>       ... normal domain XML config ...
>      </domain>
>    </domstate>
> And so have a function
>    virDomainObjPtr virDomainObjParse(const char *filename)
> which'd parse the custom QEMU state, and then just invoke  the
> virDomainDefParseNode for the nested <domain> tag.
Yes, nice - this simplifies things. I'll try that.

> Now, some things like VNC port, domain ID really are easily tracked
> in the regular domain XML - rather than adding VIR_DOMAIN_XML_STATE
> I've a slight alternative idea.
> The formatXML methods already accept a flag VIR_DOMAIN_XML_INACTIVE
> which when passed causes it to skip some attributes which only
> make sense for running VMs - VNC port, ID, VIF name
> The parseXML methods, just hardcode this and always skip these
> attributes. We should fix this so the parsing only skips these
> attrs if this same VIR_DOMAIN_XML_INACTIVE flag is passed. Then
> just make sure all existing code is changed to set this flag
> when parsing XML. The code for loading VM from disk can simply
> not set this flag. Technically the LXC driver shold be doing
> this already, precisely for the VIF name issue.
Like the attached patch?
 -- Guido
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-differentiate-between-active-and-inactive-configs.patch
Type: text/x-diff
Size: 9022 bytes
Desc: not available
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20081130/6569016d/attachment-0001.bin>

More information about the libvir-list mailing list