All Vlan network created
In Vlan network mode, I create a pool of network (10 for example) with nova-mange. I create a new project. Nova associate a network for this project. I start an instance. nova-compute create all bridges/VLANs (10 for the example) of the pool networks.
Why all VLANs/bridges are created and not only the one of the network associate to the project ?