Comment 7 for bug 1718979

Reviewed: https://review.openstack.org/517341
Committed: https://git.openstack.org/cgit/openstack/openstack-ansible-lxc_hosts/commit/?id=be93ac8d3f1ba7f1e786c835436b4839cfbc0932
Submitter: Zuul
Branch: stable/pike

commit be93ac8d3f1ba7f1e786c835436b4839cfbc0932
Author: Kevin Carter <email address hidden>
Date: Mon Oct 30 20:54:12 2017 -0500

    Combined backport to fix issues and enhance efficiency

    The LXC host role can be tuned up for better overall efficiency.

    Highlights:
    * Move async wait to a later position for role performance. The
      async wait we're doing can be moved elsewhere in the role so
      that we're able to do more in parallel. This change simply moves
      the async wait to a postition just before its required.
    * Move container creation tasks into their own sub-files which are
      accessed using dynamic routing.
    * Several syntatic items were cleaned up.
    * All of the basic cache cleanup has been moved to handlers.

    These changes further optimise the lxc_host role so that it's using more
    of the built in modules and making better use of handlers.

    Moving the dnsmasq process to a unit file gives operators the ability to
    restart the dnsmasq process if there's an issue with the service. It
    also ensures the service stays running as systemd will take better care
    of the service by isolating it within a specific cgroup, ensuring good
    reporting and memory management, and providing the ability to recover
    from failures in an automated way.

    Closes-Bug: #1718979
    Closes-Bug: #1518485
    (cherry picked from commit 076493d01485822b1efbc962478150278ecbf566)
    (cherry picked from commit 53a6cce9ed08dc5005a42f064a3b8811d65f9d70)

    Change-Id: If7dfbae19429cb033d7fd7e33f1423627f091534