AccountsService is unusable with large numbers of users and groups in Red Hat Enterprise Linux 7

Issue

• We've been trying to get gdm to work in our environment and have discovered that RH7 now requires the use of AccountsService to do so.
• We have 58000 entries in /etc/passwd and over 1200 in /etc/group.
• The account-daemon, gnome-shell, and gnome-initial-setup process are all consuming large amounts of CPU and memory as they try to load all of those entries.
• It appears that they're trying to iterate over all of the home directories looking for .face files.