Re: [ovirt-devel] [vdsm] Engine XML: metadata and devices from XML

On 03/17/2017 11:07 PM, Michal Skrivanek wrote: >> On 17 Mar 2017, at 15:57, Francesco Romani <fromani(a)redhat.com&gt; wrote: >> >> On 03/16/2017 08:03 PM, Francesco Romani wrote: >>> On 03/16/2017 01:26 PM, Francesco Romani wrote: >>>> On 03/16/2017 11:47 AM, Michal Skrivanek wrote: >>>>>> On 16 Mar 2017, at 09:45, Francesco Romani <fromani(a)redhat.com&gt; wrote: >>>>>> >>>>>> We talked about sending storage device purely on metadata, letting Vdsm >>>>>> rebuild them and getting the XML like today. >>>>>> >>>>>> In the other direction, Vdsm will pass through the XML (perhaps only >>>>>> parts of it, e.g. the devices subtree) like before. >>>>>> >>>>>> This way we can minimize the changes we are uncertain of, and more >>>>>> importantly, we can minimize the risky changes. >>>>>> >>>>>> >>>>>> The following is a realistic example of how the XML could look like if >>>>>> we send all but the storage devices. It is built using my pyxmlpickle >>>>>> module (see [3] below). >>>>> That’s quite verbose. How much work would it need to actually minimize it and turn it into something more simple. >>>>> Most such stuff should go away and I believe it would be beneficial to make it difficult to use to discourage using metadata as a generic junkyard >>>> It is verbose because it is generic - indeed perhaps too generic. >>>> I can try something else based on a concept from Martin Polednik. Will >>>> follow up soon. >>> Early preview: >>> https://gerrit.ovirt.org/#/q/status:open+project:vdsm+branch:master+topic... >>> >>> still plenty of TODOs, I expect to be reviewable material worst case >>> monday morning. >> This is how typical XML could look like: >> >> <metadata> >> <ovirt-tune:qos /> >> <ovirt-vm:vm /> >> <devices> >> <ovirt-instance:graphics> > not under the <ovirt-vm:vm>? > any reason? No reason, I'll move under it