[Errno 24] Too many open files error on simple deployment with neutron

Steps to reproduce:
235 iso:
Ubuntu simple with murano:
network: neutron untagged vlan
1 controller + 4 compute

1. Set each network on separate interface
2. Untagg networks
3. Run network verification
4. Run deployment
5. When deployment finish with succes - run all ostf tests

Expected result:
tests are passed

Actual result:
Some instance failed to get ACTIVE state, stack in build status. Also I can no delete them. All qemu processes are run.
As soon as test are fail on step wait until instance become Active - next trace appear in nova-api
http://paste.openstack.org/show/73128/

on controller we can see that nova -api has more than 1024 opened fd (1024 set by default value for open files ulimit -n show 1024)
root@node-14:~# lsof -p 16906 | wc -l
2150

If we set for this limit value 65534 (in /etc/init/nova-api.conf)
root@node-14:~# cat /etc/init/nova-api.conf

http://paste.openstack.org/show/73168/

restart nova services and run ostf omne more time - mysql go away
2014-03-11T16:37:39.409592+00:00 debug: 2014-03-11 16:37:36.545 16906 DEBUG routes.middleware [-] Route path: '/{project_id}/flavors/:(id)', defaults: {'action': u'show', 'controller': <nova.api.openstack.wsgi.Resource object at 0x311d190>} __call__ /usr/lib/python2.7/dist-packages/routes/middleware.py:102
2014-03-11T16:37:39.409592+00:00 debug: 2014-03-11 16:37:36.546 16906 DEBUG routes.middleware [-] Match dict: {'action': u'show', 'controller': <nova.api.openstack.wsgi.Resource object at 0x311d190>, 'project_id': u'97b7d83d8c4d4af29193cdfd9568fd9b', 'id': u'7867'} __call__ /usr/lib/python2.7/dist-packages/routes/middleware.py:103
2014-03-11T16:37:39.409592+00:00 debug: 2014-03-11 16:37:36.548 16906 DEBUG nova.api.openstack.wsgi [req-db385363-e90d-477f-b22b-a7429d9c544d a8565eac62a84d5787d3e9b9e6d1aa4a 97b7d83d8c4d4af29193cdfd9568fd9b] No Content-Type provided in request get_body /usr/lib/python2.7/dist-packages/nova/api/openstack/wsgi.py:835
2014-03-11T16:37:39.409592+00:00 debug: 2014-03-11 16:37:36.548 16906 DEBUG nova.api.openstack.wsgi [req-db385363-e90d-477f-b22b-a7429d9c544d a8565eac62a84d5787d3e9b9e6d1aa4a 97b7d83d8c4d4af29193cdfd9568fd9b] Calling method <bound method Controller.show of <nova.api.openstack.compute.flavors.Controller object at 0x311d110>> _process_stack /usr/lib/python2.7/dist-packages/nova/api/openstack/wsgi.py:962
2014-03-11T16:37:39.409592+00:00 debug: 2014-03-11 16:37:36.555 16906 WARNING nova.openstack.common.db.sqlalchemy.session [req-db385363-e90d-477f-b22b-a7429d9c544d a8565eac62a84d5787d3e9b9e6d1aa4a 97b7d83d8c4d4af29193cdfd9568fd9b] Got mysql server has gone away: (2006, 'MySQL server has gone away')

also in we run netstat - there is a lot of next rows:
tcp 0 0 10.108.1.2:8774 10.108.1.2:54348 ESTABLISHED 16906/python

Reproduced 2 times from 2 attempts
in logs controller nodes are 14 for second deployment and 11 for first attemp