Thanks to everybody who has commented on the Cyborg/Nova scheduling spec (https://review.openstack.org/#/c/554717/). As you may have noted, some issues were raised (*1), discussed (*2) and a potential solution was offered (*3). I have tried to synthesize the new solution from Nova team here: https://etherpad.openstack.org/p/Cyborg-Nova-Multifunction This simplifies Cyborg design/implementation, by having the weigher use Placement info (no queries or extra info in Cyborg DB), and by opening the possibility of removing the weigher altogether if/when Nova supports preferred traits. Please review it. Once that is done. I'll post an update that includes the new scheme and addresses any applicable comment in the current spec. Thank you very much! (*1) http://lists.openstack.org/pipermail/openstack-dev/2018-March/128685.html (*2) http://lists.openstack.org/pipermail/openstack-dev/2018-March/128840.html, 128889.html, etc. (*3) http://lists.openstack.org/pipermail/openstack-dev/2018-March/128888.html Regards, Sundar