</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>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
- (resp. files) they control. Example: the swap device
- <filename>/dev/sda5</filename> must be configured in a
+ 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 (resp. on the mount points
- of the files) they are activated from.</para>
+ 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
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>
+ <para>When reading <filename>/etc/fstab</filename> a
+ few special options are understood by systemd which
+ influence how dependencies are created for swap
+ units.</para>
+
+ <variablelist class='fstab-options'>
+ <varlistentry>
+ <term><option>noauto</option></term>
+ <term><option>auto</option></term>
+
+ <listitem><para>With <option>noauto</option> the
+ swap unit will not be added as a dependency for
+ <filename>swap.target</filename>. This means that
+ it will not be activated automatically during
+ boot, unless it is pulled in by some other
+ unit. Option <option>auto</option> has the
+ opposite meaning and is the default.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>nofail</option></term>
+ <term><option>fail</option></term>
+
+ <listitem><para>With <option>nofail</option> the
+ swap unit will be only wanted, not required by
+ <filename>swap.target</filename>. This means that
+ the boot will continue even if this swap device is
+ not activated successfully. Option
+ <option>fail</option> has the opposite meaning and
+ is the default.</para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
</refsect1>
<refsect1>
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>. The
+ <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>
setting is optional.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>Options=</varname></term>
+
+ <listitem><para>May contain an option
+ string for the swap device. This may
+ be used for controlling discard
+ options among other functionality, if
+ the swap backing device supports the
+ discard or trim operation. (See
+ <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+ for more information.)
+ </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
+ within the configured time, the swap
will be considered failed and be shut
down again. All commands still running
will be terminated forcibly via
- SIGTERM, and after another delay of
- this time with SIGKILL. (See
- <option>KillMode=</option> below.)
+ <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
- 90s.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><varname>KillMode=</varname></term>
- <listitem><para>Specifies how
- processes of this swap shall be
- killed. One of
- <option>control-group</option>,
- <option>process</option>,
- <option>none</option>.</para>
-
- <para>This option is mostly equivalent
- to the <option>KillMode=</option>
- option of service files. See
- <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
- for details.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><varname>KillSignal=</varname></term>
- <listitem><para>Specifies which signal
- to use when killing a process of this
- swap. Defaults to SIGTERM.
- </para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><varname>SendSIGKILL=</varname></term>
- <listitem><para>Specifies whether to
- send SIGKILL to remaining processes
- after a timeout, if the normal
- shutdown procedure left processes of
- the swap around. Takes a boolean
- value. Defaults to "yes".
+ 20s". Pass <literal>0</literal> to disable the timeout
+ logic. Defaults to <varname>DefaultTimeoutStartSec=</varname> from the
+ manager configuration file
+ (see <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
</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>1</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</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>systemd-fstab-generator</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