Concurrent Memory Upgrade

An IBM z16 includes a function to dynamically increase the amount of configured storage. Concurrent Memory Upgrade allows for a memory upgrade without changing hardware or experiencing an outage, provided there is enough spare memory existing on the memory cards. An IML is not required to use the previously unavailable storage. It is immediately available for allocation to logical partitions as central storage. The new storage can be allocated to either newly activated logical partitions or to already active logical partitions by using dynamic storage reconfiguration (see Dynamic storage reconfiguration). In planning for a concurrent memory upgrade, logical partition activation profiles should be defined with storage (central) specifications that include a reserved as well as an initial storage amount. Following the completion of the concurrent memory upgrade operation, issue the z/OS® command CF STOR(E=1),ONLINE to bring the new memory online to already active LPs for which a reserved central storage amount was specified. For z/VM®, following the completion of the concurrent memory upgrade operation, issue the z/VM SET STORAGE command, to bring the new memory online to already active LPs for which a reserved central storage amount was specified. See the "Host Storage Planning and Administration" chapter in z/VM CP Planning and Administration, SC24-6271.