CSET-SET(1) [FIXME: manual] CSET-SET(1)NAMEcset-set - manage sets of cpus
SYNOPSIS
cset [cset options] set [set options] [args]
cset set --help
cset set
cset set --recurse
cset set --list myset
cset set myset
cset set --recurse --list myset
cset set --cpu 2-5 --mem 0 --set newset
cset set --cpu 2-5 newset
cset set --cpu 1,2,5-7 another_set
cset set --destroy newset
cset set --destroy /mygroup_sets/my_set
OPTIONS-h, --help
prints the list of options for this command
-l, --list
list the named cpuset(s); if -a is used, will list members of named
cpuset; if -r is used, will list recursively
-c CPUSPEC, --cpu=CPUSPEC
create or modify cpuset in the specified cpuset with CPUSPEC
specification
-m MEMSPEC, --mem=MEMSPEC
specify which memory nodes to assign to the created or modified
cpuset
-d, --destroy
destroy specified cpuset
-s CPUSET, --set=CPUSET
specify cpuset name to be acted on
-r, --recurse
do recursive listing, for use with --list
-v, --verbose
prints more detailed output, for the set command, using this flag
will not chop listing to fit in 80 columns
--cpu_exclusive
mark this cpuset as owning its CPUs exclusively
--mem_exclusive
mark this cpuset as owning its MEMs exclusively
DESCRIPTION
This command is used to create, modify, and destroy cpusets. Cpusets
form a tree-like structure rooted at the root cpuset which always
includes all system CPUs and all system memory nodes.
A cpuset is an organizational unit that defines a group of CPUs and a
group of memory nodes where a process or thread (i.e. task) is allowed
to run on. For non-NUMA machines, the memory node is always 0 (zero)
and cannot be set to anything else. For NUMA machines, the memory node
can be set to a similar specification as the CPU definition and will
tie those memory nodes to that cpuset. You will usually want the memory
nodes that belong to the CPUs defined to be in the same cpuset.
A cpuset can have exclusive right to the CPUs defined in it. This means
that only this cpuset can own these CPUs. Similarly, a cpuset can have
exclusive right to the memory nodes defined in it. This means that only
this cpuset can own these memory nodes.
Cpusets can be specified by name or by path; however, care should be
taken when specifying by name if the name is not unique. This tool will
generally not let you do destructive things to non-unique cpuset names.
Cpusets are uniquely specified by path. The path starts at where the
cpusets filesystem is mounted so you generally do not have to know
where that is. For example, so specify a cpuset that is called "two"
which is a subset of "one" which in turn is a subset of the root
cpuset, use the path "/one/two" regardless of where the cpusets
filesystem is mounted.
When specifying CPUs, a so-called CPUSPEC is used. The CPUSPEC will
accept a comma-separated list of CPUs and inclusive range
specifications. For example, --cpu=1,3,5-7 will assign CPU1, CPU3,
CPU5, CPU6, and CPU7 to the specified cpuset.
Note that cpusets follow certain rules. For example, children can only
include CPUs that the parents already have. If you do not follow those
rules, the kernel cpuset subsystem will not let you create that cpuset.
For example, if you create a cpuset that contains CPU3, and then
attempt to create a child of that cpuset with a CPU other than 3, you
will get an error, and the cpuset will not be active. The error is
somewhat cryptic in that it is usually a "Permission denied" error.
Memory nodes are specified with a MEMSPEC in a similar way to the
CPUSPEC. For example, --mem=1,3-6 will assign MEM1, MEM3, MEM4, MEM5,
and MEM6 to the specified cpuset.
Note that if you attempt to create or modify a cpuset with a memory
node specification that is not valid, you may get a cryptic error
message, "No space left on device", and the modification will not be
allowed.
When you destroy a cpuset, then the tasks running in that set are moved
to the parent of that cpuset. If this is not what you want, then
manually move those tasks to the cpuset of your choice with the cset
proc command (see cset proc --help for more information).
EXAMPLES
Create a cpuset with the default memory specification
# cset set --cpu=2,4,6-8 --set=new_set
This command creates a cpuset called "new_set" located off the root
cpuset which holds CPUS 2,4,6,7,8 and node 0 (interleaved) memory. Note
that --set is optional, and you can just specify the name for the new
cpuset after all arguments.
Create a cpuset that specifies both CPUs and memory nodes
# cset set --cpu=3 --mem=3 /rad/set_one
Note that this command uses the full path method to specify the name of
the new cpuset "/rad/set_one". It also names the new cpuset implicitly
(i.e. no --set option, although you can use that if you want to). If
the "set_one" name is unique, you can subsequently refer to is just by
that. Memory node 3 is assigned to this cpuset as well as CPU 3.
The above commands will create the new cpusets, or if they already
exist, they will modify them to the new specifications.
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>.
SEE ALSOcset(1), cset-proc(1), cset-shield(1)
/usr/share/doc/packages/cpuset/html/tutorial.html
taskset(1), chrt(1)
/usr/src/linux/Documentation/cpusets.txt
[FIXME: source] 02/11/2010 CSET-SET(1)