CPU utilization requires rethinking when zIIP and zAAP engines are involved. Google is your friend: cpu utilization ziip
returns about 4,980 hits and some of them, even on the first page of results, talk about the impact of the new engines on CPU measurement. But basically, measuring CPU utilization becomes more complicated since work can be zIIP-eligible, zIIP-qualified, GP (general processor), and overflow (zIIP-qualified work that ran on the GP because the zIIP engine couldn't get it done).
You would be wise to look at CMG's web site (http://www.cmg.org
) as well since I'm sure they have had some interesting discussions on measurement of CPU with the new engines.