Red Hat Bugzilla – 2040554 – netdev_dpdk logged "Failed to create memory pool for netdev with MTU 1500" even though MTUs of all DPDK NICs were configured as 9000.
i have filed an upstream bug to track eventually optimising os-vif to set the port mtu atomically as part of the port creation to avoid this error message.
https://bugs.launchpad.net/os-vif/+bug/1959586
for now however I will not have time to work on this.