Comment 2 for bug 1554105

Reviewed: https://review.openstack.org/295348
Committed: https://git.openstack.org/cgit/openstack/solar/commit/?id=e2cfa869d808c9c52d8b75bf63e05078f16feeeb
Submitter: Jenkins
Branch: master

commit e2cfa869d808c9c52d8b75bf63e05078f16feeeb
Author: Dmitry Shulyak <email address hidden>
Date: Mon Mar 21 17:08:31 2016 +0200

    Implement traversal based on number of childs

    By using childs weights for scheduling we can unlock
    concurrent and decrease total time of execution.

    As an example consider next variant:
    Tasks A and B can't run concurrently because of node-limit.
    Tasks A and C have logical dependency, and thus not concurrent.
    Tasks B and C will be executed on different nodes, and doesnt
    have any logical dependency.
    As A and B doesnt have parents we may schedule any of this task
    and logically execution will be correct, but in case if we will choose
    B total time of execution will be - B + A + C, BUT
    if we will select A - total time of execution may be reduced,
    and will take in total - A + max(B, C).

    Change-Id: I52a6c20e8c3d729ed20da822f45cbad90e51f2df
    Closes-Bug: 1554105