IBM z13s, Technical Manual

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IBM z13s Technical Guide
7.3.11 Separate LPAR management of PUs
The z13s uses separate PU pools for each optional PU type. The separate management of
PU types enhances and simplifies capacity planning and management of the configured
LPARs and their associated processor resources. Table 7-14 lists the support requirements
for the separate LPAR management of PU pools.
Table 7-14 Minimum support requirements for separate LPAR management of PUs
7.3.12 Dynamic LPAR memory upgrade
An LPAR can be defined with both an initial and a reserved amount of memory. At activation
time, the initial amount is made available to the partition and the reserved amount can be
added later, partially or totally. Those two memory zones do not have to be contiguous in real
memory, but appear as logically contiguous to the operating system that runs in the LPAR.
z/OS can take advantage of this support and nondisruptively acquire and release memory
from the reserved area. z/VM V6R2 and later can acquire memory nondisruptively, and
immediately make it available to guests. z/VM virtualizes this support to its guests, which can
also increase their memory nondisruptively if supported by the guest operating system.
Releasing memory from z/VM is not supported. Releasing memory from the z/VM guest
depends on the guest’s operating system support.
Linux on z Systems also supports both acquiring and releasing memory nondisruptively. This
feature is enabled for SUSE Linux Enterprise Server 11 and RHEL 6.
Dynamic LPAR memory upgrade is not supported for zACI-mode LPARs.
7.3.13 LPAR physical capacity limit enforcement
On the IBM z13s, PR/SM is enhanced to support an option to limit the amount of physical
processor capacity that is consumed by an individual LPAR when a PU that is defined as a
central processor (CP) or an IFL is shared across a set of LPARs. This enhancement is
designed to provide a physical capacity limit that is enforced as an absolute (versus a relative)
limit. It is not affected by changes to the logical or physical configuration of the system. This
physical capacity limit can be specified in units of CPs or IFLs.
Remember: The IBM zAware virtual appliance runs in a dedicated LPAR, so when it is
activated, it reduces the maximum number of available LPARs by one.
Operating system Support requirements
z/OS z/OS V1R12
z/VM z/VM V6R2
z/VSE z/VSE V5R1
z/TPF z/TPF V1R1
Linux on z Systems SUSE Linux Enterprise Server 12
SUSE Linux Enterprise Server 11
Red Hat RHEL 7
Red Hat RHEL 6