HP-UX Workload Manager User's Guide

Configuring WLM
Defining the PRM components (optional)
Chapter 5 163
must install PSET (PROCSETS) software to obtain PSET functionality;
see the HP-UX WLM Release Notes. PSET functionality comes with
HP-UX 11i v2 (B.11.23) and later.
NOTE It is possible to create a WLM configuration that has more PSET-based
workload groups than the underlying system has cores. However, if all
the groups are active at the same time, some groups will necessarily not
have a core assigned and their processes would be placed in OTHERS.
Furthermore, if there are more PSET-based groups than cores and
transient_groups is not set to 1, the allocation of cores to the
PSET-based groups will never change. As a result, the extra groups do
not add any value as they will never get any cores.
Reserved workload groups
The PRM_SYS workload group (ID 0) is the default workload group for
system processes. It is created automatically, but you can specify it in
your configuration. You cannot however reference PRM_SYS outside a prm
structure. Also, PRM_SYS cannot be created as a PSET group.
The OTHERS workload group (ID 1) is the default workload group for all
nonsystem processes. It is also created automatically, but you can
explicitly specify it in your configuration file if you would like to assign
applications, users, Unix groups, or secure compartments to it or have
WLM manage its resources. If specified, this workload group does not
have to be referenced in an slo structure.
OTHERS cannot be created as a PSET group.
Any workload group name starting with an underscore (_) is reserved for
WLM use.
For information on slo structures, see “Defining SLOs” on page 186.
The default PSET (PSET 0) and FSS groups
With PRM-based configurations, WLM uses processor sets (PSETs) for
allocating dedicated CPU resources to designated applications and users.
At system initialization time, the default PSET is created. The default
PSET, when created at system initialization, consists of all of your
system’s processors. Afterward, the default PSET consists of all the
processors that were not assigned to other PSET groups. All FSS groups
reside in the default PSET, where all FSS group CPU allocation occurs.
The system administrator can create additional PSET groups and assign