Comment 68 for bug 1813703

Reviewed: https://review.openstack.org/649688
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=39afe0a129b6b979d0b56ec59048a4e16bedf7a9
Submitter: Zuul
Branch: stable/queens

commit 39afe0a129b6b979d0b56ec59048a4e16bedf7a9
Author: LIU Yulong <email address hidden>
Date: Fri Apr 12 18:47:24 2019 +0300

    Do not call update_device_list in large sets

    Ovs-agent can process the ports in large sets, then all
    of these ports will have to update DB status or attributes.
    But neutron server is centralized. It may have to do
    something else, or the database processing can be also
    time-consuming. Because of these, it sometimes returns
    the RPC timeout exception to ovs-agent. And a fullsync
    will be triggered in next rpc loop. The restart time is
    becoming longer and longer.

    Adds a default step to update the port to reduce
    the probability of RPC timeout.

    Related-Bug: #1813703
    Related-Bug: #1813704
    Related-Bug: #1813706
    Related-Bug: #1813707

    Conflicts:
     neutron/tests/unit/plugins/ml2/test_rpc.py

    Change-Id: Ie37f4a4869969e235ce16b73cdfcbdc98626823e
    (cherry picked from commit 8408af4f173a0ffde354599e26c49bf9e17e8bef)
    (cherry picked from commit d7d30ea950844f11348fa2827908622e3a8c7dfb)
    (cherry picked from commit 5d705468de1e495639f8b87266ccfc9391ce6135)