[Engine-devel] Add traffic shaping parameters for a network interface.

[Giuseppe Vallarelli]

----- Original Message -----
| From: "Dan Kenigsberg" <danken at redhat.com>
| To: "Giuseppe Vallarelli" <gvallare at redhat.com>
| Cc: engine-devel at ovirt.org
| Sent: Monday, June 10, 2013 4:22:54 PM
| Subject: Re: [Engine-devel] Add traffic shaping parameters for a network interface.
| 
| On Mon, Jun 10, 2013 at 08:56:21AM -0400, Giuseppe Vallarelli wrote:
| > Hi Guys, I've recently submitted a patch to support traffic shaping for a
| > network interface (http://gerrit.ovirt.org/#/c/15445/).
| > This work is needed in order to support
| > http://www.ovirt.org/Features/Network_QoS .
| > Given:
| > 
| > 'specParams': {'inbound': {'average': '1000', 'peak': '5000', 'burst':
| > '1024'},
| >                'outbound': {'average': '128', 'burst': '256'}}}
| > 
| > Generated xml is the following one:
| > 
| > 
| > 
| > 
| > 
| > 
| > As you can see I tried to keep the data structure as flat as possible
| > having the bandwidth element not carrying any useful information.
| > Feedback is highly appreciated.
| > 
| 
| The issue has not been mentioned on the wiki page, but may need a means
| to report the currently-configured QoS of each vNIC from Vdsm to Engine.
| For example, when a VM is de-hibernated, we may want to tell whether its
| QoS needs to be set according to a recently-tweaked policy.
| 
| I suggest that we use the "getVmList" verb of Vdsm, which is intended to
| report "static" properties of one Vm (or all of them).
| 
| On the other hand, Engine would want to blindly set new values whenever
| in doubt. In such a case, I think that reporting of QoS can be avoided.
| 
| Dan.
| 

I'm not sure I've understood completely the issue in discussion, doesn't the engine knows already
which are the QoS profile applied to each vNIC ? The last 'tweaked' profile is the one that should
be applied after de-hibernation. This means that on the engine side we should keep track of profile
change, if a change happens de-hibernating a vm triggers a QoS profile update on the host of the
latest profile. I'm not aware of the implementation details so I might be wrong.

Giuseppe.