Comment 16 for bug 1679750

@Henry, if you need to cleanup placement, there is the osc-placement CLI plugin available for some of this:

https://docs.openstack.org/osc-placement/latest/index.html

i.e. you can remove allocations for a given consumer (deleted instance) if nova failed to cleanup allocations for that instance when it was deleted. That's a workaround until we have a fix for this bug in nova.