Different constraints may influence
what capacity a z/OS® system
can consume. There are different ways how to relieve the constrains:
If the overall processing capacity of your zEnterprise server
(CPC) get exhausted, in order to relief the bottleneck additional
physical capacity needs to be activated via the On/Off Capacity on
Demand (On/Off CoD) feature.
An installation may use Variable Workload License Charge (VWLC)
and has configured defined capacity. Defined capacity comes in two
flavors:
a capacity limit for a single logical partition (LPAR). This is
referred to as Defined Capacity by Capacity Provisioning. In other
documentation, this may also be referred to as LPAR defined capacity,
or soft capping.
a capacity limit for a group of logical partitions. Such a capacity
group is a named configuration element that is defined on a Support
Element of a CPC. This is referred to as Group Capacity by Capacity
Provisioning. In other documentation, it may also be referred to as
group defined capacity.
For a workload, Defined Capacity, Group Capacity, or both types
of defined capacity can be in effect. The capacity limit for defined
capacity is measured in million service units (MSU) per hour, our
just MSU for short. When your workload is constrained by defined
capacity, the capacity limit needs to be increased to resolve the
bottleneck.
A system may be constrained by the number of online logical processors,
and more logical processors need to be configured online to resolve
the constraint.
z/OS Capacity Provisioning can help
you identifying and resolving capacity bottlenecks, or constraints,
that may impact important workloads. Because both, the analysis of
configuration and performance data, and eventual actions, as defined
in your Capacity Provisioning policies, are automated, problems may
be addressed more timely than through human action.
For example, you can:
Activate and deactivate capacity
through operator commands.
Activate and deactivate capacity
based on a defined schedule, without considering workload performance.
Have the Provisioning Manager suggest
changes to the capacity of the System z10™ or zEnterprise server based
on the observation of workloads that you define.
Have the Provisioning Manager automatically implement changes
to the capacity of the System z server based on the observation of
workloads that you define.
Table 1. Capacity Provisioning Features
Type of Resource
Capacity Provisioning can
monitor for capacity shortage based on your policy
Capacity Provisioning can
alert you to address capacity shortage based on your policy
Capacity Provisioning can
resolve capacity shortage based on your policy (with or without additional
confirmation)
Commands for manual control
CPC physical general purpose processor capacity
Yes
Yes
Yes
Yes - valid
On/Off CoD record required
CPC zIIP and zAAP processor capacity
Yes
Yes
Yes
Yes - valid
On/Off CoD record required
CPC IFL, ICF, and SAP processor capacity
No
No
No
Yes - valid
On/Off CoD record required
Logical processor capacity
Yes
Yes
No
Via MVS CONFIG
command
Defined Capacity, Group Capacity
Yes
Yes
Yes
Yes
Note:
Capacity Provisioning
supports Group Capacity on IBM zEnterprise z196 servers and later.