]>
Commit | Line | Data |
---|---|---|
1 | <?xml version='1.0'?> <!--*-nxml-*--> | |
2 | <?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?> | |
3 | <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" | |
4 | "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> | |
5 | ||
6 | <!-- | |
7 | This file is part of systemd. | |
8 | ||
9 | Copyright 2010 Lennart Poettering | |
10 | ||
11 | systemd is free software; you can redistribute it and/or modify it | |
12 | under the terms of the GNU Lesser General Public License as published by | |
13 | the Free Software Foundation; either version 2.1 of the License, or | |
14 | (at your option) any later version. | |
15 | ||
16 | systemd is distributed in the hope that it will be useful, but | |
17 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
18 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
19 | Lesser General Public License for more details. | |
20 | ||
21 | You should have received a copy of the GNU Lesser General Public License | |
22 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
23 | --> | |
24 | ||
25 | <refentry id="systemd.swap"> | |
26 | <refentryinfo> | |
27 | <title>systemd.swap</title> | |
28 | <productname>systemd</productname> | |
29 | ||
30 | <authorgroup> | |
31 | <author> | |
32 | <contrib>Developer</contrib> | |
33 | <firstname>Lennart</firstname> | |
34 | <surname>Poettering</surname> | |
35 | <email>lennart@poettering.net</email> | |
36 | </author> | |
37 | </authorgroup> | |
38 | </refentryinfo> | |
39 | ||
40 | <refmeta> | |
41 | <refentrytitle>systemd.swap</refentrytitle> | |
42 | <manvolnum>5</manvolnum> | |
43 | </refmeta> | |
44 | ||
45 | <refnamediv> | |
46 | <refname>systemd.swap</refname> | |
47 | <refpurpose>Swap unit configuration</refpurpose> | |
48 | </refnamediv> | |
49 | ||
50 | <refsynopsisdiv> | |
51 | <para><filename><replaceable>swap</replaceable>.swap</filename></para> | |
52 | </refsynopsisdiv> | |
53 | ||
54 | <refsect1> | |
55 | <title>Description</title> | |
56 | ||
57 | <para>A unit configuration file whose name ends in | |
58 | <literal>.swap</literal> encodes information about a | |
59 | swap device or file for memory paging controlled and | |
60 | supervised by systemd.</para> | |
61 | ||
62 | <para>This man page lists the configuration options | |
63 | specific to this unit type. See | |
64 | <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
65 | for the common options of all unit configuration | |
66 | files. The common configuration items are configured | |
67 | in the generic [Unit] and [Install] sections. The swap | |
68 | specific configuration options are configured in the | |
69 | [Swap] section.</para> | |
70 | ||
71 | <para>Additional options are listed in | |
72 | <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
73 | which define the execution environment the | |
74 | <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry> | |
75 | binary is executed in, and in | |
76 | <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
77 | which define the way the processes are | |
78 | terminated, and in | |
79 | <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
80 | which configure resource control settings for the | |
81 | processes of the service.</para> | |
82 | ||
83 | <para>Swap units must be named after the devices | |
84 | or files they control. Example: the swap device | |
85 | <filename noindex='true'>/dev/sda5</filename> must be configured in a | |
86 | unit file <filename>dev-sda5.swap</filename>. For | |
87 | details about the escaping logic used to convert a | |
88 | file system path to a unit name, see | |
89 | <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para> | |
90 | ||
91 | <para>All swap units automatically get the appropriate | |
92 | dependencies on the devices or on the mount points | |
93 | of the files they are activated from.</para> | |
94 | ||
95 | <para>Swap units with | |
96 | <varname>DefaultDependencies=</varname> enabled | |
97 | implicitly acquire a conflicting dependency to | |
98 | <filename>umount.target</filename> so that they are | |
99 | deactivated at shutdown.</para> | |
100 | </refsect1> | |
101 | ||
102 | <refsect1> | |
103 | <title><filename>fstab</filename></title> | |
104 | ||
105 | <para>Swap units may either be configured via unit | |
106 | files, or via <filename>/etc/fstab</filename> (see | |
107 | <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
108 | for details). Swaps listed in | |
109 | <filename>/etc/fstab</filename> will be converted into | |
110 | native units dynamically at boot and when the | |
111 | configuration of the system manager is | |
112 | reloaded. See | |
113 | <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry> | |
114 | for details about the conversion.</para> | |
115 | ||
116 | <para>If a swap device or file is configured in both | |
117 | <filename>/etc/fstab</filename> and a unit file, the | |
118 | configuration in the latter takes precedence.</para> | |
119 | ||
120 | <para>Unless the <option>noauto</option> option is set | |
121 | for them all swap units configured in | |
122 | <filename>/etc/fstab</filename> are also added as | |
123 | requirements to <filename>swap.target</filename>, so | |
124 | that they are waited for and activated during | |
125 | boot.</para> | |
126 | </refsect1> | |
127 | ||
128 | <refsect1> | |
129 | <title>Options</title> | |
130 | ||
131 | <para>Swap files must include a [Swap] section, which | |
132 | carries information about the swap device it | |
133 | supervises. A number of options that may be used in | |
134 | this section are shared with other unit types. These | |
135 | options are documented in | |
136 | <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
137 | and | |
138 | <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The | |
139 | options specific to the [Swap] section of swap units | |
140 | are the following:</para> | |
141 | ||
142 | <variablelist class='unit-directives'> | |
143 | ||
144 | <varlistentry> | |
145 | <term><varname>What=</varname></term> | |
146 | <listitem><para>Takes an absolute path | |
147 | of a device node or file to use for | |
148 | paging. See | |
149 | <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry> | |
150 | for details. If this refers to a | |
151 | device node, a dependency on the | |
152 | respective device unit is | |
153 | automatically created. (See | |
154 | <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
155 | for more information.) If this refers | |
156 | to a file, a dependency on the | |
157 | respective mount unit is automatically | |
158 | created. (See | |
159 | <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
160 | for more information.) This option is | |
161 | mandatory.</para></listitem> | |
162 | </varlistentry> | |
163 | ||
164 | <varlistentry> | |
165 | <term><varname>Priority=</varname></term> | |
166 | ||
167 | <listitem><para>Swap priority to use | |
168 | when activating the swap device or | |
169 | file. This takes an integer. This | |
170 | setting is optional.</para></listitem> | |
171 | </varlistentry> | |
172 | ||
173 | <varlistentry> | |
174 | <term><varname>TimeoutSec=</varname></term> | |
175 | <listitem><para>Configures the time to | |
176 | wait for the swapon command to | |
177 | finish. If a command does not exit | |
178 | within the configured time, the swap | |
179 | will be considered failed and be shut | |
180 | down again. All commands still running | |
181 | will be terminated forcibly via | |
182 | <constant>SIGTERM</constant>, and after another delay of | |
183 | this time with <constant>SIGKILL</constant>. (See | |
184 | <option>KillMode=</option> in | |
185 | <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>.) | |
186 | Takes a unit-less value in seconds, or | |
187 | a time span value such as "5min | |
188 | 20s". Pass <literal>0</literal> to disable the timeout | |
189 | logic. Defaults to <varname>DefaultTimeoutStartSec=</varname> from the | |
190 | manager configuration file | |
191 | (see <citerefentry><refentrytitle>systemd-systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>). | |
192 | </para></listitem> | |
193 | </varlistentry> | |
194 | </variablelist> | |
195 | ||
196 | <para>Check | |
197 | <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
198 | and | |
199 | <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
200 | for more settings.</para> | |
201 | </refsect1> | |
202 | ||
203 | <refsect1> | |
204 | <title>See Also</title> | |
205 | <para> | |
206 | <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, | |
207 | <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, | |
208 | <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
209 | <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
210 | <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
211 | <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
212 | <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
213 | <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
214 | <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry>, | |
215 | <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>, | |
216 | <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry> | |
217 | </para> | |
218 | </refsect1> | |
219 | ||
220 | </refentry> |