Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
+ Lesser General Public License for more details.
- You should have received a copy of the GNU General Public License
+ You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
<refnamediv>
<refname>systemd.swap</refname>
- <refpurpose>systemd swap configuration files</refpurpose>
+ <refpurpose>Swap unit configuration</refpurpose>
</refnamediv>
<refsynopsisdiv>
- <para><filename>systemd.swap</filename></para>
+ <para><filename><replaceable>swap</replaceable>.swap</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>A unit configuration file whose name ends in
- <filename>.swap</filename> encodes information about a
+ <literal>.swap</literal> encodes information about a
swap device or file for memory paging controlled and
supervised by systemd.</para>
specific configuration options are configured in the
[Swap] section.</para>
- <para>Swap units must be named after the devices they
- control. Example: the swap device
- <filename>/dev/sda5</filename> must be configured in a
+ <para>Additional options are listed in
+ <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ which define the execution environment the
+ <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ binary is executed in, and in
+ <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ which define the way the processes are
+ terminated, and in
+ <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ which configure resource control settings for the
+ processes of the service.</para>
+
+ <para>Swap units must be named after the devices
+ or files they control. Example: the swap device
+ <filename noindex='true'>/dev/sda5</filename> must be configured in a
unit file <filename>dev-sda5.swap</filename>. For
details about the escaping logic used to convert a
- file system path to a unit name see
+ file system path to a unit name, see
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+
+ <para>All swap units automatically get the appropriate
+ dependencies on the devices or on the mount points
+ of the files they are activated from.</para>
+
+ <para>Swap units with
+ <varname>DefaultDependencies=</varname> enabled
+ implicitly acquire a conflicting dependency to
+ <filename>umount.target</filename> so that they are
+ deactivated at shutdown.</para>
</refsect1>
<refsect1>
<para>Swap units may either be configured via unit
files, or via <filename>/etc/fstab</filename> (see
<citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
- for details).</para>
+ for details). Swaps listed in
+ <filename>/etc/fstab</filename> will be converted into
+ native units dynamically at boot and when the
+ configuration of the system manager is
+ reloaded. See
+ <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ for details about the conversion.</para>
<para>If a swap device or file is configured in both
- <filename>/etc/fstab</filename> and a unit file the
+ <filename>/etc/fstab</filename> and a unit file, the
configuration in the latter takes precedence.</para>
+
+ <para>Unless the <option>noauto</option> option is set
+ for them all swap units configured in
+ <filename>/etc/fstab</filename> are also added as
+ requirements to <filename>swap.target</filename>, so
+ that they are waited for and activated during
+ boot.</para>
</refsect1>
<refsect1>
<para>Swap files must include a [Swap] section, which
carries information about the swap device it
- supervises. The options specific to the [Swap] section
- of swap units are the following:</para>
+ supervises. A number of options that may be used in
+ this section are shared with other unit types. These
+ options are documented in
+ <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ and
+ <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
+ options specific to the [Swap] section of swap units
+ are the following:</para>
- <variablelist>
+ <variablelist class='unit-directives'>
<varlistentry>
<term><varname>What=</varname></term>
paging. See
<citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry>
for details. If this refers to a
- device node a dependency on the
+ device node, a dependency on the
respective device unit is
automatically created. (See
<citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for more information.) If this refers
- to a file a dependency on the
+ to a file, a dependency on the
respective mount unit is automatically
created. (See
<citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
file. This takes an integer. This
setting is optional.</para></listitem>
</varlistentry>
+
+ <varlistentry>
+ <term><varname>TimeoutSec=</varname></term>
+ <listitem><para>Configures the time to
+ wait for the swapon command to
+ finish. If a command does not exit
+ within the configured time, the swap
+ will be considered failed and be shut
+ down again. All commands still running
+ will be terminated forcibly via
+ <constant>SIGTERM</constant>, and after another delay of
+ this time with <constant>SIGKILL</constant>. (See
+ <option>KillMode=</option> in
+ <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>.)
+ Takes a unit-less value in seconds, or
+ a time span value such as "5min
+ 20s". Pass 0 to disable the timeout
+ logic. Defaults to <varname>TimeoutStartSec=</varname> from the
+ manager configuration file.</para></listitem>
+ </varlistentry>
</variablelist>
+
+ <para>Check
+ <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ and
+ <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ for more settings.</para>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
- <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
</para>
</refsect1>
~ianmdlvl / elogind.git / blobdiff