Comment 3 for bug 1653880

Reviewed: https://review.openstack.org/416400
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=9a022e7d7b85b7c21cf26698fe59c818c4577194
Submitter: Jenkins
Branch: master

commit 9a022e7d7b85b7c21cf26698fe59c818c4577194
Author: Kevin Benton <email address hidden>
Date: Tue Jan 3 18:10:36 2017 -0800

    Reduce IP link show calls for SR-IOV scan loop

    The device scanning logic was calling 'ip link show' for every
    vf_index on the system, which was taking an excessive amount of
    time an CPU cycles on very dense SR-IOV servers (>64 interfaces).
    This was being executed every 2 seconds so it would cause the
    agent to take a large percentage of the CPU time.

    This patch adjusts the logic to use two 'ip link show' commands for
    checking all of the operations in a single get_assigned_devices_info
    call.

    Closes-Bug: #1653880
    Change-Id: I361caaf7f70580ee8c7b48a4a9c9477bdefd8b4b