Multiple CBU records may be active at the same time. CBU resources can be activated, deactivated, or the activation level changed concurrently (from an LPAR perspective). I assume you're using shared processors only and z/OS. Usually, from z/OS you may need to configure additional logical processors online to utilize more logicals from a given LPAR, or (recommended) configure logicals offline before physically deactivating resources, if the new number of physical processors in the shared processor pool would be less than the number of logicals online to any single partition. You cannot extend the CBU resources *from a given record* beyond the grace period. The Capacity on Demand user's Guide for your hardware model is a good resource, e.g., regarding the grace period handling. In general, there should be no reason for IPLing z/OS unless you had disabled DYNCPADD in your LOADxx, or you would be running out of the limit and you need to utilize more logical processors. z/OS subsystems are usually well prepared to deal with model changes.
Horst Sinram - STSM, z/OS Workload and Capacity Management ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
