Comment 12 for bug 1414218

Reviewed: https://review.openstack.org/176679
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=59b9735af1b4004c5877c5f87ccae114c63f06e0
Submitter: Jenkins
Branch: stable/juno

commit 59b9735af1b4004c5877c5f87ccae114c63f06e0
Author: Ihar Hrachyshka <email address hidden>
Date: Mon Apr 20 17:06:38 2015 +0200

    tests: confirm that _output_hosts_file does not log too often

    I3ad7864eeb2f959549ed356a1e34fa18804395cc didn't include any regression unit
    tests to validate that the method won't ever log too often again,
    reintroducing performance drop in later patches. It didn't play well
    with stable backports of the fix, where context was lost when doing the
    backport, that left the bug unfixed in stable/juno even though the patch
    was merged there [1].

    The patch adds an explicit note in the code that suggests not to add new
    log messages inside the loop to avoid regression, and a unit test was
    added to capture it.

    Once the test is merged in master, it will be proposed for stable/juno
    inclusion, with additional changes that would fix the regression again.

    Conflicts:
     neutron/agent/linux/dhcp.py
     neutron/tests/unit/test_linux_dhcp.py

    Local changes:
    - remove LOG.debug messages that sneaked into the for loop with a
      backport.

    Related-Bug: #1414218
    Change-Id: I5d43021932d6a994638c348eda277dd8337cf041
    (cherry picked from commit 3b74095a935f6d2027e6bf04cc4aa21f8a1b46f2)