OVSLibTestCase.test_db_find_column_type_list is not isolated

[Henry Gessau]

Spotted in a functional test log:

neutron.tests.functional.agent.test_ovs_lib.OVSLibTestCase.test_db_find_column_type_list(vsctl)
-----------------------------------------------------------------------------------------------

Captured traceback:
~~~~~~~~~~~~~~~~~~~
    Traceback (most recent call last):
      File "neutron/tests/functional/agent/test_ovs_lib.py", line 395, in test_db_find_column_type_list
        self.assertEqual(tags_present, len_0_list)
      File "/opt/stack/new/neutron/.tox/dsvm-functional/local/lib/python2.7/site-packages/testtools/testcase.py", line 411, in assertEqual
        self.assertThat(observed, matcher, message)
      File "/opt/stack/new/neutron/.tox/dsvm-functional/local/lib/python2.7/site-packages/testtools/testcase.py", line 498, in assertThat
        raise mismatch_error
    testtools.matchers._impl.MismatchError: [{u'tag': 42}, {u'tag': 1}] != [{u'tag': 42}, {u'tag': 1}, {u'tag': 1567}]

Note the extra {'tag': 1567}.

[Dariusz Smigiel (smigiel-dariusz)]

Started failing recently:
http://logstash.openstack.org/#dashboard/file/logstash.json?query=message%3A%5C%22testtools.matchers._impl.MismatchError%3A%20%5B%7Bu'tag'%5C%22%20AND%20project%3A%5C%22openstack%2Fneutron%5C%22%20AND%20build_name%3A%5C%22gate-neutron-dsvm-functional%5C%22

[Armando Migliaccio (armando-migliaccio)]

Any update?

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/345296

[Boden R (boden)]

Based on the logstash query I'm using [1] we have 6 hits in the past 30 days.

The current fix out for review doesn't seem address the issue here.

[1] http://logstash.openstack.org/#dashboard/file/logstash.json?query=message%3A%5C%22AssertionError%3A%20Sequences%20differ%5C%22%20AND%20project%3A%5C%22openstack%2Fneutron%5C%22%20AND%20build_name%3A%5C%22gate-neutron-dsvm-functional%5C%22

[Henry Gessau (gessau)]

I should explain my terminology. By "not isolated" I mean that some other test case seems to adding a port with a tag while this test is running. I don't know ovsdb details, but the ovsdb.db_find() does not seem to be restricted to the port created for the test case, so I guess it will find tags for all ports.

[Boden R (boden)]

Henry: yep we're on the same page.

Please have a look at the updated patch; I'm hoping it addresses the root cause.

Also I spoke to the "old" bug owner and they are fine with me taking this over.

[Boden R (boden)]

Also, for the record: not sure why this is 'low' as there have been some intermittent gate failures recently.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/345296
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=319bc525b408c6df1905e9597da28c2d1ce3020c
Submitter: Jenkins
Branch: master

commit 319bc525b408c6df1905e9597da28c2d1ce3020c
Author: Boden R <email address hidden>
Date: Thu Jul 21 15:07:41 2016 +0530

    isolate test_db_find_column_type_list

    As per the recent gate failures (see bug), it appears
    OVSLibTestCase.test_db_find_column_type_list is not isolated
    and thus its usage of ovsdb's db_list() and db_find() occasionally
    obtain different results.

    This patch adds the db_list() and db_find() operations within the
    test case to run in a transaction so that we get a single snapshot
    of the db results.

    In addition this patch undoes the changes from patch set 1 as the
    initial changes do not appear to address the issue at hand.

    Change-Id: I312076edb6e11f21347831843758894e11d6f56c
    Closes-Bug: #1592546

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 9.0.0.0b3 development milestone.