Technical data

Processor Sets (Psets) on nPartitions
Introduction to Psets
HP System Partitions Guide: Administration for nPartitions, rev 5.1 425
Pset Binding and
Inheritance
Child threads and processes inherit the Pset bindings of their parents.
So, for example, when a process creates child processes, the children are
are launched into the same Pset as the parent.
By using the Pset programming interface you can have more control over
the Pset locations where threads and processes are spawned and run.
Using PRM on
nPartitions with
Psets
The HP Process Resource Manager product enables you to create and
manage Psets through its graphical interface.
PRM provides the ability to maintain Pset configurations across system
reboots. It also has the ability to assign (isolate) memory to Psets, thus
giving Psets memory isolation as well as processor resource isolation.
PRM software refers to Psets that it tracks using PRM IDs or names,
rather than using Pset IDs. PRM may modify Psets and cause them to be
renumbered while managing Psets. Thus, if you use the psrset -i
command while PRM has configured Psets, you may notice this
renumbering of Pset IDs.
Note that if you have used PRM to assign specific processor IDs to Psets
in the system, all specified processor IDs must be present for PRM to be
able to load and establish the Pset configurations. Otherwise, when
specified processors are not present, PRM cannot create the Psets.
You can help avoid this potential problem by not specifying processor IDs
and instead specifying the number of processors for PRM to configure in
each Pset.
This processor availability issue can prevent PRM from loading Pset
configurations when iCOD software in an nPartition has deactivated one
or more of the specified processors.
PRM also may be prevented from loading Pset configurations when any
of the following has occurred in an nPartition: deconfiguring processors
(at the BCH interface), unassigning a cell from an nPartition, or making
one or more of an nPartition’s cells inactive.
For details on managing PRM, see the PRM online help or HP Process
Resource Manager User’s Guide. Also see the psrset (1M) manpage for
details on using the -f option while PRM is managing Psets.
Programming
Interface for Psets
For details on the Pset programming interface, see the following HP-UX
manpages: pset_assign (2), pset_bind (2), pset_create (2), pset_ctl (2),
pset_destroy (2), pset_getattr (2), pset_setattr (2).