Choosing a Policy Type

How do you decide which policy type to use? The table below answers this question for several common use cases. The section following the table helps you decide between using an OwnBorrow policy or a utilization policy.

Table 1-1 Choosing a policy type

If...	Use the following type of policy...
You want gWLM to allocate a constant amount of CPU to a workload	Fixed
IT acts as a service provider to business units	OwnBorrow This policy type allows you to set an owned amount of resources, while also giving you control over how workloads borrow and lend resources. gWLM provides a “topborrowers” report and a “resourceaudit” report to help you manage your data center using this model. For more information, refer to the gwlmreport(1M) manpage.
You have static vpars but you want to move to a model where CPUs migrate among vpars	OwnBorrow For each vpar, set its number of owned CPUs to its static number of CPUs. The vpar gets those owned CPUs whenever needed.
You have npars but you want to move to a model where CPUs migrate among npars	OwnBorrow Install the HP Instant Capacity product on each npar. (This software allows gWLM to simulate CPU movement among the npars.) For each npar, set its number of owned CPUs to the number of CPUs you want the npar to have whenever needed.
You want to tap into a pool of resources taking or giving CPU resources as needed—with no guaranteed access to resources beyond a minimum request	Utilization

Choosing Between an OwnBorrow Policy and a Utilization Policy

OwnBorrow policies allocate a certain amount of CPU resources to your workload. This amount is based on the owned CPU resources specified in the policy. The workload can lend unneeded resources to other workloads—and get those resources back when they are needed again.

With utilization policies, gWLM allocates CPU resources to the workload based on the minimum CPU value specified in the policy. These resources cannot be shared with other workloads.

Combining the Different Policy Types

Each workload in an SRD must have a policy. Starting with gWLM A.02.00.00.x, you can use any combination of the policy types within an SRD.

If you are managing systems with earlier gWLM releases, you must follow the policy combinations allowed with those releases. With gWLM versions prior to A.02.00.00.x, combinations of policies within a single SRD were limited to the combinations shown in the following table.

Table 1-2 gWLM A.01.x: Compatible combinations of policy types

Policy type	Fixed	Utilization	OwnBorrow	Custom
Fixed	Yes	Yes	Yes	Yes
Utilization	Yes	Yes	—	Yes
OwnBorrow	Yes	—	Yes	—
Custom	Yes	Yes	—	Yes

Choosing a Policy Type

Technical documentation

» Table of Contents

Choosing Between an OwnBorrow Policy and a Utilization Policy

Combining the Different Policy Types