[libvirt] [PATCH-RFC] qemu: Add network bandwidth setting for ethernet interfaces

[Anirban Chakraborty]

On 9/7/14, 2:01 AM, "Martin Kletzander" <mkletzan at redhat.com> wrote:

>On Fri, Sep 05, 2014 at 11:42:58PM +0000, Anirban Chakraborty wrote:
>>
>>
>>On 9/5/14, 1:31 AM, "Martin Kletzander" <mkletzan at redhat.com> wrote:
>>
>>>On Thu, Sep 04, 2014 at 03:02:54PM -0700, Anirban Chakraborty wrote:
>>>><snip>
>It doesn't, actually.  <interface type='ethernet'><source
>dev="tap123"/> ... makes use of the device tap123 that already exists
>and leaves it in the system.  When I start and stop the domain with
>the bandwidth set, it is kept in there.  If I were to start another
>domain without any bandwidth setting (or just use the device somehow),
>the speed would be affected.
>
>Probably taking Laine's approach would be cleaner and easier (it could
>also take care of this automagically).

You are right that tap device is not deleted (as libvirt doesn¹t create it
either) for ethernet type interfaces. However, for all other interface
types, corresponding tap device is deleted. So, if I clear the bandwidth
setting in a generic way it will become redundant for these other
interface types. In any case, I¹ll ensure that the tap device
configurations are cleared out in the unplug and shutdown path.

Anirban