Expanded Storage Layout - IBM Z9 Planning Manual

Addressable
Figure 3-9. Expanded Storage Layout
Notice that the total amount of expanded storage addressability that can be used
to map expanded storage for LPs is at least twice the amount of installed storage.
Figure 3-10 on page 3-23, Figure 3-11 on page 3-23, Figure 3-12 on page 3-24, and
Figure 3-13 on page 3-25 describe examples of dynamic reconfiguration of
expanded storage. For this example, assume the amount of installed storage is 32
GB. The amount of physical central storage used by hardware system area (HSA)
is 2GB in this example leaving 30 GB of physical storage for allocation to LPs. The
storage granularity is 64 MB so the HSA addressable storage size is 2048 MB. This
leaves 1022 GB of central storage addressability to be allocated to LPs.
LP-A is defined with an initial amount of 14 GB of central storage, an initial amount
of 2 GB of expanded storage and a reserved amount of 2 GB of expanded storage,
and system determined central storage origins. The origin of central storage used to
back online expanded storage is always system determined and in this case is
coincidentally but not necessarily contiguous with the addressability used to back
the logical partition's initial central storage amount. LP-B is defined with an initial
amount of 14 GB of central storage, and a reserved amount of 2 GB of central
storage, with a system determined central storage origin. LP-A and LP-B are
activated and IPLed. At the completion of IPL, LP-B has its reserved central storage
configured online by entering CF STOR(E=1),ONLINE from the z/OS software
console for LP-B. Figure 3-10 on page 3-23 shows the resulting storage layout
following these actions.
3-22
PR/SM Planning Guide
1024 GB
1023 GB
1022 GB
ORIG = none
Storage
1021 GB
1020 GB
ORIG = none
1019 GB
Installed
Storage
0 GB
LP-B (ES1) not populated (offline)
LP-B (ES0)
INIT = 1 GB
LP-A (ES1) not populated (offline)
LP-A (ES0)
INIT = 1 GB
Unused Addressability
LP-B's
addressable
range
RSVD = 1 GB
LP-A's
addressable
RSVD = 1 GB
range
1 GB
available