resource_controls(5) Standards, Environments, and Macros resource_controls(5)NAMEresource_controls - resource controls available through project data‐
base
DESCRIPTION
The resource controls facility is configured through the project data‐
base. See project(4). You can set and modify resource controls through
the following utilities:
o prctl(1)
o projadd(1M)
o projmod(1M)
o rctladm(1M)
In a program, you use setrctl(2) to set resource control values.
In addition to the preceding resource controls, there are resource
pools, accessible through the pooladm(1M) and poolcfg(1M) utilities. In
a program, resource pools can be manipulated through the libpool(3LIB)
library.
The following are the resource controls are available:
process.max-address-space
Maximum amount of address space, as summed over segment sizes, that
is available to this process, expressed as a number of bytes.
process.max-core-size
Maximum size of a core file created by this process, expressed as a
number of bytes.
process.max-cpu-time
Maximum CPU time that is available to this process, expressed as a
number of seconds.
process.max-data-size
Maximum heap memory available to this process, expressed as a num‐
ber of bytes.
process.max-file-descriptor
Maximum file descriptor index available to this process, expressed
as an integer.
process.max-file-size
Maximum file offset available for writing by this process,
expressed as a number of bytes.
process.max-msg-messages
Maximum number of messages on a message queue (value copied from
the resource control at msgget() time), expressed as an integer.
process.max-msg-qbytes
Maximum number of bytes of messages on a message queue (value
copied from the resource control at msgget() time), expressed as a
number of bytes.
process.max-port-events
Maximum allowable number of events per event port, expressed as an
integer.
process.max-sem-nsems
Maximum number of semaphores allowed per semaphore set, expressed
as an integer.
process.max-sem-ops
Maximum number of semaphore operations allowed per semop call
(value copied from the resource control at semget() time).
Expressed as an integer, specifying the number of operations.
process.max-stack-size
Maximum stack memory segment available to this process, expressed
as a number of bytes.
project.cpu-caps
Maximum amount of CPU resources that a project can use. The unit
used is the percentage of a single CPU that can be used by all user
threads in a project. Expressed as an integer. The cap does not
apply to threads running in real-time scheduling class. This
resource control does not support the syslog action.
project.cpu-shares
Number of CPU shares granted to a project for use with the fair
share scheduler (see FSS(7)). The unit used is the number of shares
(an integer). This resource control does not support the syslog
action.
project.max-contracts
Maximum number of contracts allowed in a project, expressed as an
integer.
project.max-crypto-memory
Maximum amount of kernel memory that can be used for crypto opera‐
tions. Allocations in the kernel for buffers and session-related
structures are charged against this resource control.
project.max-locked-memory
Total amount of physical memory locked by device drivers and user
processes (including D/ISM), expressed as a number of bytes.
project.max-lwps
Maximum number of LWPs simultaneously available to a project,
expressed as an integer.
project.max-msg-ids
Maximum number of message queue IDs allowed for a project,
expressed as an integer.
project.max-port-ids
Maximum allowable number of event ports, expressed as an integer.
project.max-sem-ids
Maximum number of semaphore IDs allowed for a project, expressed as
an integer.
project.max-shm-ids
Maximum number of shared memory IDs allowed for a project,
expressed as an integer.
project.max-shm-memory
Total amount of shared memory allowed for a project, expressed as a
number of bytes.
project.max-tasks
Maximum number of tasks allowable in a project, expressed as an
integer.
project.pool
Binds a specified resource pool with a project.
rcap.max-rss
The total amount of physical memory, in bytes, that is available to
processes in a project.
task.max-cpu-time
Maximum CPU time that is available to this task's processes,
expressed as a number of seconds.
task.max-lwps
Maximum number of LWPs simultaneously available to this task's pro‐
cesses, expressed as an integer.
The following zone-wide resource controls are available:
zone.cpu-cap
Sets a limit on the amount of CPU time that can be used by a zone.
The unit used is the percentage of a single CPU that can be used by
all user threads in a zone. Expressed as an integer. When projects
within the capped zone have their own caps, the minimum value takes
precedence. This resource control does not support the syslog
action.
zone.cpu-shares
Sets a limit on the number of fair share scheduler (FSS) CPU shares
for a zone. CPU shares are first allocated to the zone, and then
further subdivided among projects within the zone as specified in
the project.cpu-shares entries. Expressed as an integer. This
resource control does not support the syslog action.
zone.max-locked-memory
Total amount of physical locked memory available to a zone.
zone.max-lwps
Enhances resource isolation by preventing too many LWPs in one zone
from affecting other zones. A zone's total LWPs can be further sub‐
divided among projects within the zone within the zone by using
project.max-lwps entries. Expressed as an integer.
zone.max-msg-ids
Maximum number of message queue IDs allowed for a zone, expressed
as an integer.
zone.max-sem-ids
Maximum number of semaphore IDs allowed for a zone, expressed as an
integer.
zone.max-shm-ids
Maximum number of shared memory IDs allowed for a zone, expressed
as an integer.
zone.max-shm-memory
Total amount of shared memory allowed for a zone, expressed as a
number of bytes.
zone.max-swap
Total amount of swap that can be consumed by user process address
space mappings and tmpfs mounts for this zone.
See zones(5).
Units Used in Resource Controls
Resource controls can be expressed as in units of size (bytes), time
(seconds), or as a count (integer). These units use the strings speci‐
fied below.
Category Res Ctrl Modifier Scale
Type String
-----------------------------------
Size bytes B 1
KB 2^10
MB 2^20
GB 2^30
TB 2^40
PB 2^50
EB 2^60
Time seconds s 1
Ks 10^3
Ms 10^6
Gs 10^9
Ts 10^12
Ps 10^15
Es 10^18
Count integer none 1
K 10^3
M 10^6
G 10^9
T 10^12
P 10^15
Es 10^18
Scaled values can be used with resource controls. The following example
shows a scaled threshold value:
task.max-lwps=(priv,1K,deny)
In the project file, the value 1K is expanded to 1000:
task.max-lwps=(priv,1000,deny)
A second example uses a larger scaled value:
process.max-file-size=(priv,5G,deny)
In the project file, the value 5G is expanded to 5368709120:
process.max-file-size=(priv,5368709120,deny)
The preceding examples use the scaling factors specified in the table
above.
Note that unit modifiers (for example, 5G) are accepted by the
prctl(1), projadd(1M), and projmod(1M) commands. You cannot use unit
modifiers in the project database itself.
Resource Control Values and Privilege Levels
A threshold value on a resource control constitutes a point at which
local actions can be triggered or global actions, such as logging, can
occur.
Each threshold value on a resource control must be associated with a
privilege level. The privilege level must be one of the following three
types:
basic
Can be modified by the owner of the calling process.
privileged
Can be modified by the current process (requiring sys_resource
privilege) or by prctl(1) (requiring proc_owner privilege).
system
Fixed for the duration of the operating system instance.
A resource control is guaranteed to have one system value, which is
defined by the system, or resource provider. The system value repre‐
sents how much of the resource the current implementation of the oper‐
ating system is capable of providing.
Any number of privileged values can be defined, and only one basic
value is allowed. Operations that are performed without specifying a
privilege value are assigned a basic privilege by default.
The privilege level for a resource control value is defined in the
privilege field of the resource control block as RCTL_BASIC, RCTL_PRIV‐
ILEGED, or RCTL_SYSTEM. See setrctl(2) for more information. You can
use the prctl command to modify values that are associated with basic
and privileged levels.
In specifying the privilege level of privileged, you can use the abbre‐
viation priv. For example:
task.max-lwps=(priv,1K,deny)
Global and Local Actions on Resource Control Values
There are two categories of actions on resource control values: global
and local.
Global actions apply to resource control values for every resource con‐
trol on the system. You can use rctladm(1M) to perform the following
actions:
o Display the global state of active system resource controls.
o Set global logging actions.
You can disable or enable the global logging action on resource con‐
trols. You can set the syslog action to a specific degree by assigning
a severity level, syslog=level. The possible settings for level are as
follows:
o debug
o info
o notice
o warning
o err
o crit
o alert
o emerg
By default, there is no global logging of resource control violations.
Local actions are taken on a process that attempts to exceed the con‐
trol value. For each threshold value that is placed on a resource con‐
trol, you can associate one or more actions. There are three types of
local actions: none, deny, and signal=. These three actions are used as
follows:
none
No action is taken on resource requests for an amount that is
greater than the threshold. This action is useful for monitoring
resource usage without affecting the progress of applications. You
can also enable a global message that displays when the resource
control is exceeded, while, at the same time, the process exceeding
the threshhold is not affected.
deny
You can deny resource requests for an amount that is greater than
the threshold. For example, a task.max-lwps resource control with
action deny causes a fork() system call to fail if the new process
would exceed the control value. See the fork(2).
signal=
You can enable a global signal message action when the resource
control is exceeded. A signal is sent to the process when the
threshold value is exceeded. Additional signals are not sent if the
process consumes additional resources. Available signals are listed
below.
Not all of the actions can be applied to every resource control. For
example, a process cannot exceed the number of CPU shares assigned to
the project of which it is a member. Therefore, a deny action is not
allowed on the project.cpu-shares resource control.
Due to implementation restrictions, the global properties of each con‐
trol can restrict the range of available actions that can be set on the
threshold value. (See rctladm(1M).) A list of available signal actions
is presented in the following list. For additional information about
signals, see signal(3HEAD).
The following are the signals available to resource control values:
SIGABRT
Terminate the process.
SIGHUP
Send a hangup signal. Occurs when carrier drops on an open line.
Signal sent to the process group that controls the terminal.
SIGTERM
Terminate the process. Termination signal sent by software.
SIGKILL
Terminate the process and kill the program.
SIGSTOP
Stop the process. Job control signal.
SIGXRES
Resource control limit exceeded. Generated by resource control
facility.
SIGXFSZ
Terminate the process. File size limit exceeded. Available only to
resource controls with the RCTL_GLOBAL_FILE_SIZE property
(process.max-file-size). See rctlblk_set_value(3C).
SIGXCPU
Terminate the process. CPU time limit exceeded. Available only to
resource controls with the RCTL_GLOBAL_CPUTIME property
(process.max-cpu-time). See rctlblk_set_value(3C).
Resource Control Flags and Properties
Each resource control on the system has a certain set of associated
properties. This set of properties is defined as a set of flags, which
are associated with all controlled instances of that resource. Global
flags cannot be modified, but the flags can be retrieved by using
either rctladm(1M) or the setrctl(2) system call.
Local flags define the default behavior and configuration for a spe‐
cific threshold value of that resource control on a specific process or
process collective. The local flags for one threshold value do not
affect the behavior of other defined threshold values for the same
resource control. However, the global flags affect the behavior for
every value associated with a particular control. Local flags can be
modified, within the constraints supplied by their corresponding global
flags, by the prctl command or the setrctl system call. See setrctl(2).
For the complete list of local flags, global flags, and their defini‐
tions, see rctlblk_set_value(3C).
To determine system behavior when a threshold value for a particular
resource control is reached, use rctladm to display the global flags
for the resource control . For example, to display the values for
process.max-cpu-time, enter:
$ rctladm process.max-cpu-time
process.max-cpu-time syslog=off [ lowerable no-deny cpu-time inf seconds ]
The global flags indicate the following:
lowerable
Superuser privileges are not required to lower the privileged val‐
ues for this control.
no-deny
Even when threshold values are exceeded, access to the resource is
never denied.
cpu-time
SIGXCPU is available to be sent when threshold values of this
resource are reached.
seconds
The time value for the resource control.
Use the prctl command to display local values and actions for the
resource control. For example:
$ prctl -n process.max-cpu-time $$
process 353939: -ksh
NAME PRIVILEGE VALUE FLAG ACTION RECIPIENT
process.max-cpu-time
privileged 18.4Es inf signal=XCPU -
system 18.4Es inf none
The max (RCTL_LOCAL_MAXIMAL) flag is set for both threshold values, and
the inf (RCTL_GLOBAL_INFINITE) flag is defined for this resource con‐
trol. An inf value has an infinite quantity. The value is never
enforced. Hence, as configured, both threshold quantities represent
infinite values that are never exceeded.
Resource Control Enforcement
More than one resource control can exist on a resource. A resource con‐
trol can exist at each containment level in the process model. If
resource controls are active on the same resource at different con‐
tainer levels, the smallest container's control is enforced first.
Thus, action is taken on process.max-cpu-time before task.max-cpu-time
if both controls are encountered simultaneously.
ATTRIBUTES
See attributes(5) for a description of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Committed │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOprctl(1), pooladm(1M), poolcfg(1M), projadd(1M), projmod(1M), rct‐
ladm(1M), setrctl(2), rctlblk_set_value(3C), libpool(3LIB), project(4),
attributes(5), FSS(7)
System Administration Guide: Virtualization Using the OpenSolaris
Operating System
SunOS 5.11 2 Jul 2007 resource_controls(5)
