LIBPOOL(3LIB) Interface Libraries LIBPOOL(3LIB)


libpool - pool configuration manipulation library


cc [ flag... ] file... -lpool [ library... ]
#include <pool.h>


The functions in this library define the interface for reading and
writing resource pools configuration files, as well as that for
committing an existing configuration to becoming the running OS
configuration (with respect to partitioning subsystems). The <pool.h>
header provides type and function declarations for all library services.

The resource pools facility brings together process-bindable resources
into a common abstraction called a pool. Processor sets and other
entities can be configured, grouped, and labelled in a persistent fashion
such that workload components can be associated with a subset of a
system's total resources. The libpool library provides a C language API
for accessing this functionality, while pooladm(8), poolbind(8), and
poolcfg(8) make this facility available through command invocations from
a shell. Each of those manual pages describes aspects of the pools
facility; this page describes the properties available to the various
entities managed within the pools facility. These entities include the
system, pools, and the pset resources for processor sets.

When the pools facility is enabled on a system, the behavior of the
following functions is modified.

System Call Error Value
pset_assign(pset !=PS_QUERY) ENOTSUP
pset_bind(pset !=PS_QUERY) ENOTSUP
pset_create() ENOTSUP
pset_destroy() ENOTSUP
pset_setattr() ENOTSUP

Each active entity within the resource pools framework can have an
arbitrary collection of named, typed properties associated with it.
Properties supported by the pools framework are listed, with
descriptions, under each entity below. In general, resource properties
can be one of five types: boolean (bool), signed (int64) and unsigned
(uint64) integers, floating point (double), and string values.

All entities and resources support a string property for commenting
purposes; this property is available for use by management applications
to record descriptions and other administrator oriented data. The comment
field is not used by the default pools commands, except when a
configuration is initiated by the poolcfg utility, in which case an
informative message is placed in the system.comment property for that


Property name Type Description
system.allocate-method string Allocation method to use when
this configuration is
system.bind-default bool If specified pool not found,
bind to pool with 'pool.default'
property set to true
system.comment string User description of system string User name for the configuration
system.version int64 libpool version required to
manipulate this configuration
system.poold.log-level string poold logging level
system.poold.log-location string poold logging location
system.poold.history-file string poold decision history location
system.poold.monitor-interval uint64 poold monitoring sample interval
system.poold.objectives string poold objectives for a system.

The system.allocate-method, system.bind-default, system.comment,, system.poold.log-level, system.poold.log-location,
system.poold.history-file, system.poold.monitor-interval, and
system.poold.objectives properties are writable; the system.version
property is not.

The system.allocate-method property accepts only two values, "importance
based" and "surplus to default". The default value for this property is
"importance based". The property is optional and if it is not present the
library will allocate resources as though it were present and had the
default value. These strings are defined in <pool.h> as POA_IMPORTANCE

If "importance based" allocation is defined, then during a commit the
library will allocate resources to pools using an algorithm that observes
minimum and maximum constraints for resources but favors those resources
with greater importance.

If "surplus to default" is defined, then during a commit the library will
allocate minimum resources to all resource sets apart from default which
will receive any surplus.

The system.bind-default property defaults to true. This property
interacts with the project.pool resource control to specify the binding
behavior for processes associated with a project. If project.pool is not
specified, then this property has no effect. If project.pool is specified
and the specified pool exists, this property has no effect. If the
specified pool does not exist, perhaps because of a reconfiguration, then
this property controls the binding behavior for the project member. If
system.bind-default is true, then the project member is bound to the
default pool (identified as the pool for which pool.default is true);
otherwise the project member is refused access to the system. Care should
be taken with the pools configuration if this property is set to false,
so as to avoid denying users access to the system.

The various poold properties are used to configure the operation of

The system.poold.log-level property is used to specify the level of
detail provided in log messages. Valid values are: ALERT, CRIT, ERR,

ALERT provides the least level of detail, DEBUG the greatest. See
syslog(3C) for more information about the meaning of these debug levels.
If this property is not specified, the default value NOTICE is used.

The system.poold.log-location property is used to specify the location of
the logfiles generated by poold. The special value of "syslog" indicates
that logged messages should be written to syslog(). If this property is
not specified, the default location /var/log/pool is used.

The system.poold.history-file specifies the location of the decision
history file which is used by poold to improve the quality of its
decision making over time. If this property is not specified, the default
location /var/adm/pool is used.

The system.poold.monitor-interval property specifies the monitoring
interval (in milliseconds) to be used by poold when sampling utilization
statistics. If this property is not specified, the default value of 15
seconds is used.

The system.poold.objectives property specifies any system wide
objectives. An objectives property has the following syntax:

objectives = objective [; objective]*
objective = [n:] keyword [op] [value]

All objectives are prefixed with an optional importance. The importance
acts as a multiplier for the objective and thus increases the
significance of its contribution to the objective function evaluation. If
no importance is specified, the default value is 1.

The "wt-load" objective is the only objective to which a system element
can be set. This objective favors configurations that match resource
allocations to resource utilization. A resource set that uses more
resources will be given more resources when this objective is active. An
administrator should use this objective when he is relatively satisfied
with the constraints established using the minimum and maximum properties
and would like the DRP to manipulate resources freely within those


Property name Type Description bool Mark this pool as active, if true.
pool.comment string User description of pool.
pool.default bool Mark this pool as the default
pool, if true; see
system.bind-default property.
pool.importance int64 Relative importance of this pool;
for possible resource dispute
resolution. string User name for pool; used by
setproject(3PROJECT) as value for
'project.pool' project attribute
in project(5) database.
pool.scheduler string Scheduler class to which consumers
of this pool will be bound. This
property is optional and if not
specified, the scheduler bindings
for consumers of this pool are not
pool.sys_id int64 System-assigned pool ID.
pool.temporary bool Mark this pool as a temporary
resource; if true, this pool can
exist only in the dynamic
configuration and cannot be
committed to a configuration file.

The pool.default, pool.sys_id, and pool.temporary properties are not
writable; all other listed properties are writable.

If pool.scheduler is specified, it must be set to the name of a valid
scheduling class for the system. See the -c option for priocntl(1) for a
list of valid class names.

Processor Sets

Property name Type Description
pset.comment string User description of resource.
pset.default bool Marks default processor set.
pset.load uint64 The load for this processor set.
pset.max uint64 Maximum number of CPUs permitted
in this processor set.
pset.min uint64 Minimum number of CPUs permitted
in this processor set. string User name for resource.
pset.size uint64 Current number of CPUs in this
processor set.
pset.sys_id int64 System-assigned processor set ID.
pset.temporary bool Mark this processor set as a
temporary resource; if true, this
processor set can exist only in
the dynamic configuration and
cannot be committed to a
configuration file.
pset.type string Names resource type; value for
all processor sets is pset.
pset.units string Identifies meaning of
size-related properties; value
for all processor sets is
pset.poold.objectives string Specifies the poold objectives
for a pset.

The pset.comment, pset.max, pset.min,, and
pset.poold.objectives properties are writable; the pset.default,
pset.load, pset.size, pset.sys_id, pset.temporary, pset.type, and
pset.units properties are not.

The pset.load property represents the load on a processor set. The lowest
value for this property is 0. The value of pset.load increases in a
linear fashion with the load on the set, as measured by the number of
jobs in the system run queue.

The pset.poold.objectives property specifies an objective which is
specific to a particular pset. See the system.poold.objectives entry for
the specification of this property's syntax.

There are two types of objectives that can be set on a pset:

This objective influences the impact that locality, as
measured by lgroup data, has upon the chosen
configuration. This objective can take one of three

If set, configurations that maximize resource
locality are favored.

If set, configurations that minimize resource
locality are favored.

This is the default value for this objective. If
set, configuration favorability is uninfluenced
by resource locality.

This objective favors configurations that allocate
resources to partitions that are failing to preserve the
specified utilization objective.

These objectives are specified in terms of an operator and a value. The
operators are

The ``less than'' operator is used to indicate that the specified
value should be treated as a maximum target value.

The ``greater than'' operator is used to indicate that the specified
value should be treated as a minimum target value.

The ``about'' operator is used to indicate that the specified value
should be treated as a target value about which some fluctuation is

Only one objective of each type of operator can be set. For example, if
the ~ operator is set, the < and > operators cannot be set. It is
possible to set a < and a > operator together; the values will be
validated to ensure that they do not overlap.


Property name Type Description
cpu.comment string User description of CPU.
cpu.pinned bool CPU pinned to this processor set.
cpu.status int64 Processor status, on-line,
offline or interrupts disabled.
cpu.sys_id int64 System-assigned processor ID.

The cpu.comment, cpu.pinned, and cpu.status properties are writable.

The cpu.status property can be set only to the following values:

Set the CPU offline.

Set the CPU online.

Disable interrupt processing on the CPU.

These values are defined in <sys/processor.h> as the PS_OFFLINE,
PS_ONLINE, and PS_NOINTR macros.


The shared object provides the public interfaces defined
below. See Intro(3) for additional information on shared object

pool_associate pool_component_info
pool_component_to_elem pool_conf_alloc
pool_conf_close pool_conf_commit
pool_conf_export pool_conf_free
pool_conf_info pool_conf_location
pool_conf_open pool_conf_remove
pool_conf_rollback pool_conf_status
pool_conf_to_elem pool_conf_update
pool_conf_validate pool_create
pool_destroy pool_dissociate
pool_dynamic_location pool_error
pool_get_binding pool_get_owning_resource
pool_get_pool pool_get_property
pool_get_resource pool_get_resource_binding
pool_get_status pool_info
pool_put_property pool_query_components
pool_query_pool_resources pool_query_pools
pool_query_resource_components pool_query_resources
pool_resource_create pool_resource_destroy
pool_resource_info pool_resource_to_elem
pool_resource_transfer pool_resource_type_list
pool_resource_xtransfer pool_rm_property
pool_set_binding pool_set_status
pool_static_location pool_strerror
pool_to_elem pool_value_alloc
pool_value_free pool_value_get_bool
pool_value_get_double pool_value_get_int64
pool_value_get_name pool_value_get_string
pool_value_get_type pool_value_get_uint64
pool_value_set_bool pool_value_set_double
pool_value_set_int64 pool_value_set_name
pool_value_set_string pool_value_set_uint64
pool_version pool_walk_components
pool_walk_pools pool_walk_properties


shared object

64-bit shared object


See attributes(7) for descriptions of the following attributes:

|CSI | Enabled |
|Interface Stability | Unstable |
|MT-Level | Safe |


Intro(3), pool_component_info(3POOL), pool_conf_open(3POOL),
pool_conf_to_elem(3POOL), pool_create(3POOL), pool_error(3POOL),
pool_get_binding(3POOL), pool_get_property(3POOL),
pool_get_resource(3POOL), pool_resource_create(3POOL),
pool_value_alloc(3POOL), pool_walk_pools(3POOL), attributes(7), smf(7)


Functions in libpool can be used to manipulate static configurations even
when the pools facility is not enabled. See pooladm(8) and
pool_set_status(3POOL) for more information about enabling the pools
facility. The pools facility must be enabled, however, to modify the
dynamic configuration.

Since the Resource Pools facility is an smf(7) service, it can also be
enabled and disabled using the standard Service Management Facility (SMF)

August 19, 2019 LIBPOOL(3LIB)