Re: [libvirt] [PATCH 0/3] Transport network port data during live migration

On Mon, Oct 01, 2012 at 03:48:32AM +0000, Kyle Mestery (kmestery) wrote: > On Sep 30, 2012, at 9:44 AM, Laine Stump wrote: >> On 09/28/2012 03:58 PM, Kyle Mestery (kmestery) wrote: >>> As an example, an OpenFlow controller may have certain information about the >>> port, specific to this controller, which it may want to store with the port itself on the >>> host. This especially true if an agent exists on the host which needs to read this data, >>> update it, and use it to perform some tasks. It's convenient to have this data stored >>> as close to the port itself, which in this case is the OVS DB, and having it transferred >>> as part of the migration protocol is also very handy. >>> >> >> But how big is it, and what does it look like? (I assume it's all >> printable ASCII, since you're getting it as the output of a shell command) >> >> If it's *really* large, possibly it would go better as a subelement of >> <interface>, rather than an attribute, i.e.: >> >> <interface index='1' vporttype='openvswitch'> >> <portdata> >> blah blah blah blah >> </portdata> >> </interface> > > > Yes. it's all printable ASCII. I think at the largest, it's possible for it to be up to a few K (e.g. 2-4K > or so). So perhaps making it a subelement would be the way to go. > > As for an example, let me talk to some controller people and see if I can scrounge one up. The other reason why I want to see indicitive size is to make sure we don't risk hitting any limits on the size of the migration cookie. Daniel