2.1.d Implement and troubleshoot trunking

2.1.d [i] VTPv1, VTPv2, VTPv3, VTP pruning

You can limit the VLAN traffic passed between switches using VTP pruning.

Pruning increases available bandwidth by restricting flooded traffic to those trunk links that the traffic must use to access the destination devices. You can enable VTP pruning on a switch in VTP server mode using the vtp pruning command.
above from net acad ccnp switch lab manual
see also:
vlans-pruning-4 firewall.cx