IBM z13s Technical Manual page 151

the dynamic addition of these resources. In z/OS, this support is available since Version 1
Release 10 (z/OS V1.10).
Adding a crypto feature to a logical partition
You can plan the addition of Crypto Express5S features to an LPAR on the crypto page in the
image profile by defining the Cryptographic Candidate List, and the Usage and Control
Domain indexes, in the partition profile. By using the "Change LPAR Cryptographic Controls"
task, you can add crypto adapters dynamically to an LPAR without an outage of the LPAR.
Also, dynamic deletion or moving of these features does not require pre-planning. Support is
provided in z/OS, z/VM, z/VSE, and Linux on z Systems.
LPAR dynamic PU reassignment
The system configuration is enhanced to optimize the PU-to-CPC drawer assignment of
physical processors dynamically. The initial assignment of client-usable physical processors
to physical CPC drawers can change dynamically to better suit the actual LPAR
configurations that are in use. For more information, see 3.5.9, "Processor unit assignment"
on page 110. Swapping of specialty engines and general processors with each other, with
spare PUs, or with both, can occur as the system attempts to change LPAR configurations
into physical configurations that span the least number of CPC drawers.
LPAR dynamic PU reassignment can swap client processors of different types between CPC
drawers. For example, reassignment can swap an IFL on CPC drawer 0 with a CP on CPC
drawer 1. Swaps can also occur between PU chips within a CPC drawer or a node, and can
include spare PUs. The goals are to pack the LPAR on fewer CPC drawers and also on fewer
PU chips, based on the z13s CPC drawers' topology. The effect of this process is evident in
dedicated and shared LPARs that use HiperDispatch.
LPAR dynamic PU reassignment is transparent to operating systems.
LPAR group capacity limit
The group capacity limit feature allows the definition of a group of LPARs on a z13s system,
and limits the combined capacity usage by those LPARs. This process allows the system to
manage the group so that the group capacity limits in MSUs per hour are not exceeded. To
take advantage of this feature, you must be running z/OS V1.10 or later in the all LPARs in the
group.
PR/SM and WLM work together to enforce the capacity that is defined for the group and the
capacity that is optionally defined for each individual LPAR.
LPAR absolute capping
Absolute capping is a new logical partition control that was made available with zEC12 and is
supported on z13s servers. With this support, PR/SM and the HMC are enhanced to support
a new option to limit the amount of physical processor capacity that is consumed by an
individual LPAR when a PU is defined as a general-purpose processor (CP), zIIP, or an IFL
processor that is shared across a set of LPARs.
Unlike traditional LPAR capping, absolute capping is designed to provide a physical capacity
limit that is enforced as an absolute (versus relative) value that is not affected by changes to
the virtual or physical configuration of the system.
Absolute capping provides an optional maximum capacity setting for logical partitions that is
specified in terms of the absolute processor capacity (for example, 5.00 CPs or 2.75 IFLs).
This setting is specified independently by processor type (namely CPs, zIIPs, and IFLs) and
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Chapter 3. Central processor complex system design