Blue Swirl wrote:
> On 4/30/09, Anthony Liguori <aliguori@us.ibm.com> wrote:
>> Jan Kiszka wrote:
>>> Why not keeping all the existing infrastructure, just locking a vlan
>>> against becoming more than a point-to-point link once some conflicting
>>> optimization was applied? That should be easy to implement and to
>>> explain to the user.
>>>
>>>
>>  I think you're suggesting the same thing as me, except you are saying make
>> vlan=off implicit, and use vlan=XXX instead of id=XXX.
>>
>>  We can still make vlan=off implicit, and default id=0, so that -net tap net
>> nic,model=virtio does the right thing.  However, if a user explicitly says
>> -net tap,vlan=1 -net nic,model=virtio,vlan=1, it behaves like it used to.
> 
> Nice, though if there are two vlans, one specified without explicit ID
> and the other with ID=1, the performance will be different.

Uh, the second case should rather behave like the first. Only if the
number vlan clients grows beyond 2, point-to-point optimizations should
be disabled (unless already enabled, then adding clients should be denied).

Jan