It seems like a useful option, and it could be a more sane default,
rather than pushing the responsibility to enable this onto deployers and
provisioning tools[1]. In fact, it may be worth doing some more work to
take away some of the hassle of configuring all these things correctly,
and see if it can be automatically determined.
[1]: https://specs.openstack.org/openstack/fuel-specs/specs/7.0/jumbo-frames-between-instances.html
Related-Bug: #1527675
Change-Id: I5cbbc4660f8c4e15e59f8f5ce0419501bdd27348