Since the inception of the zIIP in 2006 there has been a limit of 1 zIIP : 1 CP on a CEC. Well now starting with the zEC12 and zBC12 that limit is being raised to 2:1 zIIP:CPs. This makes sense as the end of the zAAP processor is on the horizon. Starting with z/OS 1.11 you can run zAAP workload on a zIIP, and APAR OA38829 for z/OS V1.12 and z/OS V1.13 removes the restriction that prevents zAAP-eligible workloads from running on zIIP processors when a zAAP is installed. This allows for capacity planning as well.
- Updates to the zIIP informational site: new limit for zIIP to CP ratio, and future deprecation of zAAP processors