IBM Z9, Planning Manual

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definition for the logical partition; not the IFA or zIIP definition. Maximizing reserved
IFAs and zIIPs is still recommended to allow for concurrently adding logical IFAs or
zIIPs to the partition if needed.
WLM managed CPs cannot have dedicated CPs. Though capping of shared CPs is
also disallowed, WLM’s License Manager component may soft-cap logical CPs
when a LPs rolling 4-hour average CPU utilization has reached its defined capacity.
(See “Workload Charging by Soft-Capping to a Defined Capacity” on page 3-46.)
Processor Considerations for Linux-Only LPs
A Linux-Only mode LP can be allocated either general purpose CPs or IFLs. For
optimum cost-effectiveness, IFLs should be used whenever possible. Choose IFL
CPs on the Processor page of the Customize/Delete Activation Profile task. IFLs
can be allocated to a Linux-Only mode LP as either dedicated or shared. Unlike
Coupling Facility mode LPs, Linux-Only LPs cannot be defined with a mix of
dedicated and shared processors or a mix of general purpose and ICF processors.
Utilization of IFLs will be included in the data reported for ICF CPs in RMF Partition
Data reports and other similar reports. There is no way to distinguish on such a
report between data reported for ICF CPs and IFLs.
A Linux-Only LP, whether allocated IFLs or general purpose CPs, will not support
any of the IBM traditional operating systems (such as z/OS, TPF, or z/VSE). Only
Linux, or z/VM Version 5 with only Linux users can run in a Linux-Only mode LP.
Logical partitions defined as Linux-Only that attempt to load a traditional operating
system will be system check-stopped.
Processor Considerations for Coupling Facility LPs
Important Note
Dynamic ICF Expansion and Enhanced Dynamic ICF Expansion across ICFs
is not recommended for coupling facilities that are used for primary production
workload. All processors assigned to the coupling facility partition should be
dedicated to that logical partition if it is used used for primary production
workload.
You can define a coupling facility to use any one of the following combinations of
CP definitions:
v One or more dedicated general purpose CPs
v
One or more shared general purpose CPs
v One or more dedicated ICF CPs
v
One or more shared ICF CPs
v One or more dedicated ICF CPs and one or more shared general purpose CPs
(dynamic ICF expansion definition). Because the coupling facility is not using
more CP resource than it requires on the shared CPs, you should set the
processing weight to a high value without affecting other work during normal
operation.
v
One or more dedicated ICF CPs and one or more shared ICF CPs (enhanced
dynamic ICF expansion definition). Because the coupling facility is not using
more CP resource than it requires on the shared CPs, you should set the
processing weight to a high value without affecting other work during normal
operation.
3-30
PR/SM Planning Guide
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