minimise the number of broadcast when coordinating pipeline

[gordon chung]

when coordinated agents are enabled, a datapoint is broadcasted to all pipelines where it is then filtered. this logic can be changed to broadcast only to queues of applicable pipelines to minimise load on MQ.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/167826

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/167826
Committed: https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=1d3c452b37fe6f31f0f09ddf45408ad7e211768f
Submitter: Jenkins
Branch: master

commit 1d3c452b37fe6f31f0f09ddf45408ad7e211768f
Author: gordon chung <email address hidden>
Date: Wed Mar 25 18:45:34 2015 -0400

    broadcast data to relevant queues only

    system resources are required to broadcast messages to queues. currently,
    when requeuing data for pipeline coordination, we broadcast to all
    queues. this patch adds a check to broadcast only to relevant
    pipelines.

    Change-Id: If4cee643537fe136fdcf66acc35e2671dbd2ac74
    Closes-Bug: #1436489