Using HP-UX Workload Manager: A quick reference

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NOTE
PRM must be installed on your system for WLM to be able to
manage workgroups based on PSETs.
To place an application in a workload group based on a pSet:
1. Define the workload group based on a pSet, and assign a workload to it.
In your WLM configuration file, define your workload group in a prm structure using the groups
keyword. Assign a workload (application) to the group using the apps keyword. Use the
gmincpu statement to set the minimum CPU usage.
The following example shows the sales group as a pSet that is assigned two cores through a
gmincpu statement. (When using gmincpu for a group based on a pSet, 100 represents a
single core; thus, 200 represents two cores.) The application sales_monitor is assigned to the
group:
prm {
groups = sales : PSET;
apps = sales : /opt/sales/bin/sales_monitor;
gmincpu = sales : 200;
}
NOTE
When WLM is managing pSets, do not change pSet settings by
using the psrset command. Only use WLM to control pSets.
2. Activate the configuration:
# /opt/wlm/bin/wlmd -a config.wlm
where config.wlm. is the name of your configuration file
Providing CPU resources for a given time period
For workloads that are only needed for a certain time, whether it is once a day, week, or any other
period, WLM provides the condition keyword. This keyword is placed in an slo structure and
enables the SLO when the condition statement is true.
By default, when the SLO is not enabled, its workload group gets its gmincpu value. If this value is
not set, the workload group gets the minimum allocation possible. For FSS groups, this default is 1%
of the total CPU resources in the default pSet. (The default pSet, also referred to as pSet 0, is created
at system initialization, at which time it consists of all of your system’s processors. After initialization,
the default pSet consists of all the processors that were not assigned to other pSet groups.) If the
extended_shares tunable is set to 1, the minimum allocation is 0.2% (with incremental allocations
of 0.1%). For more information on the extended_shares tunable, see the wlmconf(4) manpage.
Setting the transient_groups keyword to 1 also changes the minimum allocation behavior.
The following figure shows the allocation for a workload group that is disabled initiallly, at which time
it is allocated 5 shares. When the SLO is enabled, the allocation increases to 50 shares.