RCAPD(8) Maintenance Commands and Procedures RCAPD(8)

NAME

rcapd - resource cap enforcement daemon

SYNOPSIS

rcapd [-d]

DESCRIPTION

The rcapd daemon enforces resource caps on collections of processes.
Per-project and per-zone physical memory caps are supported. For
information about projects, see project(5). For zones information, see
zones(7)


When the resident set size (RSS) of a collection of processes exceeds its
cap, rcapd takes action and reduces the RSS of the collection.


The virtual memory system divides physical memory into segments known as
pages. To read data from a file into memory, the virtual memory system
reads in individual pages. To reduce resource consumption, the daemon can
page out, or relocate, infrequently used pages to an area outside of
physical memory.


In the project file, caps are defined for projects that have positive
values for the following project attribute:

rcap.max-rss
The total amount of physical memory, in bytes, that is
available to the project's member processes


See project(5) for a description of project attributes.


For a system with one or more zones, you can dynamically set the
rcap.max-rss value for a zone with rcapadm(8). To set a persistent cap on
memory usage within a zone, you use zonecfg(8).


You configure rcapd through the use of rcapadm(8). The daemon can be
monitored with rcapstat(1). Configuration changes are incorporated into
rcapd by sending it SIGHUP (see kill(1)), or according to the
configuration interval (see rcapadm(8)).

OPTIONS

The following option is supported:

-d
Enable debug mode. Messages are displayed on the invoking user's
terminal.

EXAMPLES

Example 1: Setting Resident Set Size Cap Attribute

The following line in the /etc/project database sets an RSS cap of
1073741824 bytes for a project named foo.


foo:100::foo,root::rcap.max-rss=10737418240

EXIT STATUS

The following exit values are returned:

0
Successful completion.


1
An error occurred.


2
Invalid command-line options were specified.

FILES

/etc/project
Project database.

ATTRIBUTES

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


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Evolving |
+--------------------+-----------------+

SEE ALSO

rcapstat(1), svcs(1), project(5), attributes(7), smf(7), zones(7),
rcapadm(8), svcadm(8), zonecfg(8)


"Physical Memory Control Using the Resource Capping Daemon" in System
Administration Guide: Solaris Containers-Resource Management, and Solaris
Zones

NOTES

If killed with SIGKILL, rcapd can leave processes in a stopped state. Use
SIGTERM to cause rcapd to terminate properly.


A collection's RSS can exceed its cap for some time before the cap is
enforced, even if sufficient pageable memory is available. This period of
time can be reduced by shortening the RSS sampling interval with rcapadm.


The rcapd service is managed by the service management facility, smf(7),
under the service identifier:

svc:/system/rcap:default


Administrative actions on this service, such as enabling, disabling, or
requesting restart, can be performed using svcadm(8). The service's
status can be queried using the svcs(1) command.

December 19, 2006 RCAPD(8)