Description of problem:
This RFE is comming from a BZ (https://bugzilla.redhat.com/show_bug.cgi?id=2007572) where customer was trying to set up tx_queue_size (a recommendation that they received from their VNF vendor).

This is a telco customer and they have this recommendation from their VNF vendor to have tx_queue_size set for > 256.

Version-Release number of selected component (if applicable):
RHOSP16.1/RHEL8.2

How reproducible:

• RX and TX queue size are configured on director templates
  NovaLibvirtRxQueueSize: 1024
  NovaLibvirtTxQueueSize: 1024

• this is also correctly set in nova.conf
  tx_queue_size=1024
  rx_queue_size=1024

• however the libvirt domain XML only has RX settings
  [shtiwari@supportshell virsh]$ grep -e queue -e UUID virsh_-r_dumpxml_instance-00000e74
  <driver name='vhost' queues='2' rx_queue_size='1024'/>

Instance UUID is:
virsh_-r_dominfo_instance-00000e74:UUID: 2f9201e3-df6a-4099-9277-4101db156d10

Actual results:

Expected results:

Additional info: