Description of problem:

periodic-tripleo-ci-rhel-8-standalone-full-tempest-api-rhos-16.2 is failing on neutron tempest tests.

Version-Release number of selected component (if applicable):
16.2

How reproducible:

Frequently in 16.2 Integration line

Additional info:

Tempest failure:-
~~~
Captured traceback:
~~~~~~~~~~~~~~~~~~~
    b'Traceback (most recent call last):'
    b'  File "/usr/lib/python3.6/site-packages/tempest/api/network/test_networks.py", line 474, in test_bulk_create_delete_network'
    b'    body = self.networks_client.create_bulk_networks(networks=network_list)'
    b'  File "/usr/lib/python3.6/site-packages/tempest/lib/services/network/networks_client.py", line 72, in create_bulk_networks'
    b'    return self.create_resource(uri, kwargs)'
    b'  File "/usr/lib/python3.6/site-packages/tempest/lib/services/network/base.py", line 62, in create_resource'
    b'    resp, body = self.post(req_uri, req_post_data)'
    b'  File "/usr/lib/python3.6/site-packages/tempest/lib/common/rest_client.py", line 300, in post'
    b"    return self.request('POST', url, extra_headers, headers, body, chunked)"
    b'  File "/usr/lib/python3.6/site-packages/tempest/lib/common/rest_client.py", line 704, in request'
    b'    self._error_checker(resp, resp_body)'
    b'  File "/usr/lib/python3.6/site-packages/tempest/lib/common/rest_client.py", line 881, in _error_checker'
    b'    message=message)'
    b'tempest.lib.exceptions.ServerFault: Got server fault'
    b'Details: The server has either erred or is incapable of performing the requested operation.<br /><br />'
    b''
    b''
    b''
    b''

Captured pythonlogging:
~~~~~~~~~~~~~~~~~~~~~~~
    b'2021-09-13 20:20:01,253 197183 INFO     [tempest.lib.common.rest_client] Request (BulkNetworkOpsTest:test_bulk_create_delete_network): 500 POST http://192.168.24.1:9696/v2.0/networks 5.819s'
    b"2021-09-13 20:20:01,254 197183 DEBUG    [tempest.lib.common.rest_client] Request - Headers: {'Content-Type': 'application/json', 'Accept': 'application/json', 'X-Auth-Token': '<omitted>'}"
    b'        Body: {"networks": [{"name": "tempest-network--484652455"}, {"name": "tempest-network--1692691788"}]}'
    b"    Response - Headers: {'content-length': '186', 'content-type': 'application/json', 'x-openstack-request-id': 'req-22573951-41af-458b-96bb-795f486bc8ea', 'date': 'Mon, 13 Sep 2021 20:20:01 GMT', 'connection': 'close', 'status': '500', 'content-location': 'http://192.168.24.1:9696/v2.0/networks'}"
    b'        Body: b\'{"message": "The server has either erred or is incapable of performing the requested operation.<br /><br />\\\\n\\\\n\\\\n", "code": "500 Internal Server Error", "title": "Internal Server Error"}\''
    b''
~~~


Neutron server.log
~~~
2021-09-13 20:20:01.230 ERROR /var/log/containers/neutron/server.log: 16 ERROR oslo_middleware.catch_errors sqlalchemy.exc.InvalidRequestError: This Session's transaction has been rolled back due to a previous exception during flush. To begin a new transaction with this Session, first issue Session.rollback(). Original exception was: (pymysql.err.OperationalError) (1213, 'Deadlock found when trying to get lock; try restarting transaction')
~~~