Hi Dan...this is actually Kilo (yeah, I know).  The trace looks like this on the compute side, when running with a (modified for backwards compatibility) Mitaka nova-conductor.

2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task Traceback (most recent call last):
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "./usr/lib64/python2.7/site-packages/nova/openstack/common/periodic_task.py", line 224, in run_periodic_tasks
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib64/python2.7/site-packages/nova/compute/manager.py", line 4407, in update_available_resource
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     rt.update_available_resource(context)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "./usr/lib64/python2.7/site-packages/nova/compute/resource_tracker.py", line 569, in update_available_resource
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib64/python2.7/site-packages/oslo_concurrency/lockutils.py", line 445, in inner
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     return f(*args, **kwargs)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "./usr/lib64/python2.7/site-packages/nova/compute/resource_tracker.py", line 659, in _update_available_resource
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "./usr/lib64/python2.7/site-packages/nova/compute/resource_tracker.py", line 868, in _update
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib64/python2.7/site-packages/nova/pci/manager.py", line 71, in save
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     dev.save()
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib64/python2.7/site-packages/nova/objects/base.py", line 194, in wrapper
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     self._context, self, fn.__name__, args, kwargs)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib64/python2.7/site-packages/nova/conductor/rpcapi.py", line 349, in object_action
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     objmethod=objmethod, args=args, kwargs=kwargs)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib64/python2.7/site-packages/oslo_messaging/rpc/client.py", line 156, in call
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     retry=self.retry)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib64/python2.7/site-packages/oslo_messaging/transport.py", line 90, in _send
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     timeout=timeout, retry=retry)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib64/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py", line 346, in send
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     retry=retry)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib64/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py", line 337, in _send
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     raise result
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task NotImplementedError: Cannot load 'parent_addr' in the base class
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task Traceback (most recent call last):
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task 
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib/python2.7/site-packages/nova/conductor/manager.py", line 442, in _object_dispatch
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     return getattr(target, method)(*args, **kwargs)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task 
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib/python2.7/site-packages/oslo_versionedobjects/base.py", line 223, in wrapper
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     return fn(self, *args, **kwargs)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task 
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib/python2.7/site-packages/nova/objects/pci_device.py", line 236, in save
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     updates = self.obj_get_changes()
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task 
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib/python2.7/site-packages/oslo_versionedobjects/base.py", line 604, in obj_get_changes
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     changes[key] = getattr(self, key)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task 
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib/python2.7/site-packages/oslo_versionedobjects/base.py", line 67, in getter
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     self.obj_load_attr(name)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task 
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task   File "/usr/lib/python2.7/site-packages/oslo_versionedobjects/base.py", line 580, in obj_load_attr
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task     _("Cannot load '%s' in the base class") % attrname)
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task 
2016-08-15 21:57:24.524 107915 TRACE nova.openstack.common.periodic_task NotImplementedError: Cannot load 'parent_addr' in the base class