Comment 2 for bug 1790679

Reviewed: https://review.openstack.org/599737
Committed: https://git.openstack.org/cgit/openstack/stx-config/commit/?id=86d60c3c298d5737acff61f3a104731c00ac7fb2
Submitter: Zuul
Branch: master

commit 86d60c3c298d5737acff61f3a104731c00ac7fb2
Author: Tee Ngo <email address hidden>
Date: Tue Sep 4 14:06:26 2018 -0400

    Limit number of notification workers to 10 max

    The current setting of ceilometer notification workers can result in
    an excessive number in multi-node system with high core controllers.
    It should be limited to 10 max to avoid unnecessary system resources
    consumption and to improve vcpu scaling responsiveness. The degraded
    vcpu scaling performance is caused by time taken to rebuild the
    transformer caches in all workers following a swact/service restart
    as well as the increased cpu sample age in these caches.

    Tests conducted: sanity, nightly sanity and 25 iterations of vcpu
    scaling tests in multi-node system with 32-core controllers.

    Closes-Bug: #1790679

    Change-Id: I47b7f14a75846fd9765e9a2ea2fb3ca3a6cad01a
    Signed-off-by: Tee Ngo <email address hidden>