Comment 116 for bug 1578989

Reviewed: https://review.openstack.org/630999
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=648ab82a4bf07845b97c5cb62347fbde86cdc9d2
Submitter: Zuul
Branch: master

commit 648ab82a4bf07845b97c5cb62347fbde86cdc9d2
Author: Bence Romsics <email address hidden>
Date: Wed Dec 19 13:44:37 2018 +0100

    New agent attribute: resources_synced

    Agents supporting the guaranteed minimum bandwidth feature need to share
    their resource view with neutron-server and in turn with Placement too.
    The resource information is synchronized to neutron-server via the
    periodic agent heartbeat therefore transient synchronization errors are
    fixed by the next heartbeat. But synchronization to Placement is not
    done periodically, but on a (mostly) on demand basis. Therefore to fix
    transient errors of the synchronization to Placement we must remember
    the success/failure of the last synchronization attempt.

    This change implements the extension 'agent-resources-synced' and
    therefore extends the agent db model and object with a new attribute:
    'resources_synced'. This attribute in only meant to be updated
    internally. But it can be read via the API for debugging purposes.

    APIImpact: The agent resource has a new attribute: resources_synced.

    Change-Id: I757d659cea63c8172ca3618d1f581d10236f5e71
    Depends-On: https://review.openstack.org/626210
    Partial-Bug: #1578989
    See-Also: https://review.openstack.org/502306 (nova spec)
    See-Also: https://review.openstack.org/508149 (neutron spec)