xref: /freebsd/bin/cpuset/cpuset.1 (revision fa9896e082a1046ff4fbc75fcba4d18d1f2efc19)
1.\" Copyright (c) 2008 Christian Brueffer
2.\" Copyright (c) 2008 Jeffrey Roberson
3.\" All rights reserved.
4.\"
5.\" Redistribution and use in source and binary forms, with or without
6.\" modification, are permitted provided that the following conditions
7.\" are met:
8.\" 1. Redistributions of source code must retain the above copyright
9.\"    notice, this list of conditions and the following disclaimer.
10.\" 2. Redistributions in binary form must reproduce the above copyright
11.\"    notice, this list of conditions and the following disclaimer in the
12.\"    documentation and/or other materials provided with the distribution.
13.\"
14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24.\" SUCH DAMAGE.
25.\"
26.Dd July 3, 2018
27.Dt CPUSET 1
28.Os
29.Sh NAME
30.Nm cpuset
31.Nd "configure processor sets"
32.Sh SYNOPSIS
33.Nm
34.Op Fl l Ar cpu-list
35.Op Fl n Ar policy:domain-list
36.Op Fl s Ar setid
37.Ar cmd ...
38.Nm
39.Op Fl l Ar cpu-list
40.Op Fl n Ar policy:domain-list
41.Op Fl s Ar setid
42.Fl p Ar pid
43.Nm
44.Op Fl c
45.Op Fl l Ar cpu-list
46.Op Fl n Ar policy:domain-list
47.Fl C
48.Fl p Ar pid
49.Nm
50.Op Fl c
51.Op Fl l Ar cpu-list
52.Op Fl n Ar policy:domain-list
53.Op Fl j Ar jail | Fl p Ar pid | Fl t Ar tid | Fl s Ar setid | Fl x Ar irq
54.Nm
55.Fl g
56.Op Fl cir
57.Op Fl d Ar domain | Fl j Ar jail | Fl p Ar pid | Fl t Ar tid | Fl s Ar setid | Fl x Ar irq
58.Sh DESCRIPTION
59The
60.Nm
61command can be used to assign processor sets to processes, run commands
62constrained to a given set or list of processors and memory domains, and query
63information about processor binding, memory binding and policy, sets, and
64available processors and memory domains in the system.
65.Pp
66.Nm
67requires a target to modify or query.
68The target may be specified as a command, process id, thread id, a
69cpuset id, an irq, a jail, or a NUMA domain.
70Using
71.Fl g
72the target's set id or mask may be queried.
73Using
74.Fl l
75or
76.Fl s
77the target's CPU mask or set id may be set.
78If no target is specified,
79.Nm
80operates on itself.
81Not all combinations of operations and targets are supported.
82For example,
83you may not set the id of an existing set or query and launch a command
84at the same time.
85.Pp
86There are two sets applicable to each process and one private mask per thread.
87Every process in the system belongs to a cpuset.
88By default processes are started in set 1.
89The mask or id may be queried using
90.Fl c .
91Each thread also has a private mask of CPUs it is allowed to run
92on that must be a subset of the assigned set.
93And finally, there is a root set, numbered 0, that is immutable.
94This last set is the list of all possible CPUs in the system and is
95queried using
96.Fl r .
97.Pp
98Most sets include NUMA memory domain and policy information.
99This can be inspected with
100.Fl g
101and set with
102.Fl n .
103This will specify which NUMA domains are visible to the process and
104affect where anonymous memory and file pages will be stored on first access.
105Files accessed first by other processes may specify conflicting policy.
106.Pp
107When running a command it may join a set specified with
108.Fl s
109otherwise a new set is created.
110In addition, a mask for the command may be specified using
111.Fl l .
112When used in conjunction with
113.Fl c
114the mask modifies the supplied or created set rather than the private mask
115for the thread.
116.Pp
117The options are as follows:
118.Bl -tag -width ".Fl l Ar cpu-list"
119.It Fl C
120Create a new cpuset and assign the target process to that set.
121.It Fl c
122The requested operation should reference the cpuset available via the
123target specifier.
124.It Fl d Ar domain
125Specifies a NUMA domain id as the target of the operation.
126This can only be used to query the cpus visible in each numberd domain.
127.It Fl g
128Causes
129.Nm
130to print either a list of valid CPUs or, using
131.Fl i ,
132the id of the target.
133.It Fl i
134When used with the
135.Fl g
136option print the id rather than the valid mask of the target.
137.It Fl j Ar jail
138Specifies a jail id or name as the target of the operation.
139.It Fl l Ar cpu-list
140Specifies a list of CPUs to apply to a target.
141Specification may include
142numbers separated by '-' for ranges and commas separating individual numbers.
143A special list of
144.Dq all
145may be specified in which case the list includes all CPUs from the root set.
146.It Fl n Ar policy:domain-list
147Specifies a list of domains and allocation policy to apply to a target.
148Ranges may be specified as in
149.Fl l .
150Valid policies include first-touch (ft), round-robin (rr), prefer and
151interleave (il).
152First-touch allocates on the local domain when memory is available.
153Round-robin alternates between every possible domain page at a time.
154The prefer policy accepts only a single domain in the set.
155The parent of the set is consulted if the preferred domain is unavailable.
156Interleave operates like round-robin with an implementation defined stripe
157width.
158See
159.Xr domainset 9
160for more details on policies.
161.It Fl p Ar pid
162Specifies a pid as the target of the operation.
163.It Fl s Ar setid
164Specifies a set id as the target of the operation.
165.It Fl r
166The requested operation should reference the root set available via the
167target specifier.
168.It Fl t Ar tid
169Specifies a thread id as the target of the operation.
170.It Fl x Ar irq
171Specifies an irq as the target of the operation.
172.El
173.Sh EXIT STATUS
174.Ex -std
175.Sh EXAMPLES
176Create a new group with CPUs 0-4 inclusive and run
177.Pa /bin/sh
178on it:
179.Dl cpuset -c -l 0-4 /bin/sh
180.Pp
181Query the mask of CPUs the
182.Aq sh pid
183is allowed to run on:
184.Dl cpuset -g -p <sh pid>
185.Pp
186Restrict
187.Pa /bin/sh
188to run on CPUs 0 and 2 while its group is still allowed to run on
189CPUs 0-4:
190.Dl cpuset -l 0,2 -p <sh pid>
191.Pp
192Modify the cpuset
193.Pa /bin/sh
194belongs to restricting it to CPUs 0 and 2:
195.Dl cpuset -l 0,2 -c -p <sh pid>
196.Pp
197Modify the cpuset all threads are in by default to contain only
198the first 4 CPUs, leaving the rest idle:
199.Dl cpuset -l 0-3 -s 1
200.Pp
201Print the id of the cpuset
202.Pa /bin/sh
203is in:
204.Dl cpuset -g -i -p <sh pid>
205.Pp
206Move the
207.Ar pid
208into the specified cpuset
209.Ar setid
210so it may be managed with other pids in that set:
211.Dl cpuset -s <setid> -p <pid>
212.Pp
213Create a new cpuset that is restricted to CPUs 0 and 2 and move
214.Ar pid
215into the new set:
216.Dl cpuset -C -c -l 0,2 -p <pid>
217.Sh SEE ALSO
218.Xr nproc 1 ,
219.Xr cpuset 2 ,
220.Xr rctl 8
221.Sh HISTORY
222The
223.Nm
224command first appeared in
225.Fx 7.1 .
226.Sh AUTHORS
227.An Jeffrey Roberson Aq Mt jeff@FreeBSD.org
228