Moving this bug to POST for triage into Satellite 6 since the upstream issue http://projects.theforeman.org/issues/16893 has been resolved.
Tested with 70+ hosts on Sat6.3 snap 13, no significant delay experienced
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. > > For information on the advisory, and where to find the updated files, follow the link below. > > If the solution does not work for you, open a new bug report. > > https://access.redhat.com/errata/RHSA-2018:0336