There are variations of zIIP Boost, depending on how the CPC is configured, as well as the priced System Recovery Boost upgrade record offering that will allow you to take additional advantage of zIIP Boost.
The most basic type of zIIP Boost is when you have defined Initial zIIPs, and no Reserved zIIPs that are backed by real processors. In this case, the zIIP blurring will happen for the duration of the boost on your defined, entitled zIIPs and at the end of the boost period. Normally, non-zIIP eligible work will stop running on zIIPs.
zIIP Boost with Reserved zIIPs
This is the case when you have some zIIPs that are defined as reserved, and some number of those can be backed by physical zIIPs. Those reserved zIIPs that can be backed by physical zIIPs will be brought online by the system at the beginning of the boost period, and then taken offline when the boost period is over.
System Recovery Boost upgrade record
This is a new priced feature for the z15 that requires you to have purchased an annual subscription for the Boost feature for your CPC that will allow you to bring up to 20 additional physical zIIPs online to the CPC for the duration of the capacity record activation, limited by the number of unused “dark core” processors you have in your CPC.
Use the links below to learn more: