High delay in create_network

As it turned out it happens when trying to aquire lock (dragonflow code).

Take a look at the example:

stack@ubuntu200:/opt/stack/logs$ grep req-39b7765e-8606-4259-9ca9-b31e3be89691 q-svc.log | grep "Try to get lock for object"
2016-12-13 11:25:28.774 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 3512258685.
2016-12-13 11:25:30.793 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 3156869888.
2016-12-13 11:25:34.797 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 7173602260.
2016-12-13 11:25:42.807 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 4270305405.
2016-12-13 11:25:52.816 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 2411185474.
2016-12-13 11:26:02.825 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 1907166269.
2016-12-13 11:26:12.867 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 4109395117.
2016-12-13 11:26:22.895 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 3077718418.
2016-12-13 11:26:32.903 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 1294497020.
2016-12-13 11:26:43.090 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 1200496550.
2016-12-13 11:26:53.242 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 1358217871.
2016-12-13 11:27:03.265 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 9795887159.
2016-12-13 11:27:13.269 26433 INFO dragonflow.db.neutron.lockedobjects_db [req-39b7765e-8606-4259-9ca9-b31e3be89691 c_rally_6dff3601_cgAPsIVX -] Try to get lock for object 360e7d0657df4519a53a2a5be32c1aba in session 6886244371.
2016-12...

Fix proposed to branch: master
Review: https://review.openstack.org/410160

Traceback (most recent call last):
  File "/opt/stack/new/rally/rally/task/runner.py", line 73, in _run_scenario_once
    getattr(scenario_inst, method_name)(**scenario_kwargs)
  File "/opt/stack/new/rally/rally/plugins/openstack/scenarios/neutron/network.py", line 131, in run
    network = self._get_or_create_network(network_create_args)
  File "/opt/stack/new/rally/rally/common/logging.py", line 266, in wrapper
    result = f(*args, **kwargs)
  File "/opt/stack/new/rally/rally/plugins/openstack/scenarios/neutron/utils.py", line 270, in _get_or_create_network
    return self._create_network(network_create_args or {})
  File "/opt/stack/new/rally/rally/task/atomic.py", line 84, in func_atomic_actions
    f = func(self, *args, **kwargs)
  File "/opt/stack/new/rally/rally/plugins/openstack/scenarios/neutron/utils.py", line 64, in _create_network
    {"network": network_create_args})
  File "/usr/local/lib/python2.7/dist-packages/neutronclient/v2_0/client.py", line 772, in create_network
    return self.post(self.networks_path, body=body)
  File "/usr/local/lib/python2.7/dist-packages/neutronclient/v2_0/client.py", line 365, in post
    headers=headers, params=params)
  File "/usr/local/lib/python2.7/dist-packages/neutronclient/v2_0/client.py", line 288, in do_request
    resp, replybody = self.httpclient.do_request(action, method, body=body)
  File "/usr/local/lib/python2.7/dist-packages/neutronclient/client.py", line 311, in do_request
    return self.request(url, method, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/neutronclient/client.py", line 299, in request
    resp = super(SessionClient, self).request(*args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/keystoneauth1/adapter.py", line 141, in request
    return self.session.request(url, method, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/positional/__init__.py", line 101, in inner
    return wrapped(*args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/keystoneauth1/session.py", line 592, in request
    resp = send(**kwargs)
  File "/usr/local/lib/python2.7/dist-packages/keystoneauth1/session.py", line 633, in _send_request
    raise exceptions.ConnectTimeout(msg)
ConnectTimeout: Request to http://158.69.75.235:9696/v2.0/networks.json timed out

Reviewed: https://review.openstack.org/410160
Committed: https://git.openstack.org/cgit/openstack/dragonflow/commit/?id=f6f3f2d08dcc618fcf0779168e64b5bcc1d33125
Submitter: Jenkins
Branch: master

commit f6f3f2d08dcc618fcf0779168e64b5bcc1d33125
Author: yuli <email address hidden>
Date: Tue Dec 13 12:44:05 2016 +0200

    Fix lock timeout issue

    Closes-bug: #1649548

    Change-Id: Ic99263996b5f0e425e85f262d900d1ea45d5a2db