cpuset/doc/cset.txt

cset(1)
======
Alex Tsariounov <alext@novell.com>
v1.5.3, December 2010

NAME
----
cset - manage cpusets functions in the Linux kernel

SYNOPSIS
--------
[verse]
'cset' [--version | --help | --tohex]
'cset' [help <command> | <command> --help]
'cset' [cset options] <command> [command options] [args]

DESCRIPTION
-----------
NOTE: In general, you need to have root permissions to run cset.  The
tool mounts the cpusets filesystem and manipulates it.  Non-root users
do not have permission for these actions.

Cset is a Python application to make using the cpusets facilities in
the Linux kernel easier. The actual included command is called 'cset'
and it allows manipulation of cpusets on the system and provides
higher level functions such as implementation and control of a basic
cpu shielding setup.

Typical uses of cset include
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Setting up and managing a simple shielded CPU environment::
        The concept of 'shielded' cpus is that a certain number of
        cpus are partitioned off on the system and only processes that
        are of interest are run on these cpus (i.e., inside the shield).
+
For a simple shielded configuration, one typically uses three cpusets:
the root set, a system set and a user set.  'Cset' includes a super
command that implements this strategy and lets you easily manage it.
See 'cset-shield(1)' for more details.

Setting up and managing a complex shielding environment::
	Shielding can be more complex of course where concepts such as
        priority cpusets and intersecting cpuset can be used.  You can
        use 'cset' to help manage this type of shielding as well.  You
        will need to use the 'cset-set(1)' and 'cset-proc(1)'
        subcommands directly to do that.

Managing cpusets on the system::
	The cset subcommand 'cset-set(1)' allows you to create and
        destroy arbitrary cpusets on the system and assign arbitrary
        cpus and memory nodes to them.  The cpusets so created have to
        follow the Linux kernel cpuset rules.  See the 'cset-set(1)'
        subcommand for more details.

Managing processes that run on various system cpusets::
	The cset subcommand 'cset-proc(1)' allows you to manage
        processes running on various cpusets created on the system.
        You can exec new processes in specific cpusets and move tasks
        around existing cpusets.  See the 'cset-proc(1)' subcommand
        for more details.

OPTIONS
-------
The following generic option flags are available.  Additional options
are available per-command, and documented in the command-specific
documentation.

'cset' --version::
	Display version information and exits.

'cset' --help::
	Prints the synopsis and a list of all commands.

'cset' --log <filename>::
	Creates a log file for the current run.  All manner of useful
        information is stored in this file.  This is usually used to
        debug cset when things don't go as planned.

'cset' --machine::
        Makes cset output information for all operations in a format
        that is machine readable (i.e. easy to parse).

'cset' --tohex <CPUSPEC>::
        Converts a CPUSPEC (see 'cset-set(1)' for definition) to a
        hexadecimal number and outputs it.  Useful for setting IRQ
        stub affinity to a cpuset definition.

CSET COMMANDS
-------------
The cset commands are divided into groups, according to the primary
purpose of those commands.  Following is a short description of each
command. A more detailed description is available in individual
command manpages.  Those manpages are named 'cset-<command>(1)'. The
first command, 'help', is especially useful as it prints out a long
summary of what a particular command does.

'cset help command'::
        print out a lengthy summary of how the specified subcommand
        works
'cset command --help'::
        print out an extended synopsis of the specified subcommand

'cset shield'::
	supercommand to set up and manage basic shielding (see
        'cset-shield(1)')
'cset set'::
	create, modify and destroy cpusets (see 'cset-set(1)')
'cset proc'::
	create and manage processes within cpusets (see
        'cset-proc(1)')

PERSISTENT CPUSETS
------------------
To create a persistent cpuset setup, i.e. one that survives a reboot,
you need to create the file '/etc/init.d/cset'.  This distribuition of
cset includes an example cset init.d file found in
'/usr/share/doc/pacakges/cpuset' which is called 'cset.init.d'.  You
will need to alter the file to your specifications and copy it to be
the file '/etc/init.d/cset'.  See the comments in that file for more
details.

FILES
-----
If used, the init.d script '/etc/init.d/cset' starts and stops a
cpuset configuration on boot and poweroff.

Cpuset uses a configuration file if present on the system.  The file
is '/etc/cset.conf' and may contain the following options.

mountpoint = <directory_name>::
	Specify the mountpoint where the cpuset filesystem is to be
        mounted.  By default this is '/cpusets'; however, some people
        prefer to mount this in the more traditional '/dev/cpusets'.

LICENSE
-------
Cpuset is licensed under the GNU GPL V2 only.  

COPYRIGHT
---------
Copyright (c) 2008-2010 Novell Inc.

AUTHOR
------
Written by Alex Tsariounov <\alext@novell.com>

Some substrate code and ideas were taken from the excellent Stacked
GIT (stgit) v0.13 (see \http://gna.org/projects/stgit  and
\http://www.procode.org/stgit).  Stacked GIT is under GPL V2 or later.

SEE ALSO
--------
cset-set(1), cset-proc(1), cset-shield(1)

/usr/share/doc/packages/cpuset/html/tutorial.html

/usr/share/doc/packages/cpuset/cset.init.d

taskset(1), chrt(1)

/usr/src/linux/Documentation/cpusets.txt