man: split systemd.conf(5) into multiple sections

No changes in wording, let's just make a very long man page a bit more
digestable by adding sections, and then reordering settings to fit into
them.

1 files changed, 244 insertions, 217 deletions

diff --git a/man/systemd-system.conf.xml b/man/systemd-system.conf.xml
index 7c0ba8cb8b..580da9d75f 100644
--- a/man/systemd-system.conf.xml
+++ b/man/systemd-system.conf.xml
@@ -64,11 +64,9 @@
   <refsect1>
     <title>Options</title>
 
-    <para>All options are configured in the
-    [Manager] section:</para>
+    <para>All options are configured in the [Manager] section:</para>
 
     <variablelist class='config-directives'>
-
       <varlistentry>
         <term><varname>LogColor=</varname></term>
         <term><varname>LogLevel=</varname></term>
@@ -106,6 +104,65 @@
       </varlistentry>
 
       <varlistentry>
+        <term><varname>StatusUnitFormat=</varname></term>
+
+        <listitem><para>Takes <option>name</option>, <option>description</option> or
+        <option>combined</option> as the value. If <option>name</option>, the system manager will use unit
+        names in status messages (e.g. <literal>systemd-journald.service</literal>), instead of the longer
+        and more informative descriptions set with <varname>Description=</varname> (e.g. <literal>Journal
+        Logging Service</literal>). If <option>combined</option>, the system manager will use both unit names
+        and descriptions in status messages (e.g. <literal>systemd-journald.service - Journal Logging
+        Service</literal>).</para>
+
+        <para>See
+        <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
+        details about unit names and <varname>Description=</varname>.</para>
+
+        <xi:include href="version-info.xml" xpointer="v243"/></listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>DefaultTimerAccuracySec=</varname></term>
+
+        <listitem><para>Sets the default accuracy of timer units. This
+        controls the global default for the
+        <varname>AccuracySec=</varname> setting of timer units, see
+        <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        for details. <varname>AccuracySec=</varname> set in individual
+        units override the global default for the specific unit.
+        Defaults to 1min. Note that the accuracy of timer units is
+        also affected by the configured timer slack for PID 1, see
+        <varname>TimerSlackNSec=</varname> above.</para>
+
+        <xi:include href="version-info.xml" xpointer="v212"/></listitem>
+      </varlistentry>
+    </variablelist>
+  </refsect1>
+
+  <refsect1>
+    <title>Resource Management</title>
+
+    <variablelist class='config-directives'>
+      <varlistentry>
+        <term><varname>TimerSlackNSec=</varname></term>
+
+        <listitem><para>Sets the timer slack in nanoseconds for PID 1,
+        which is inherited by all executed processes, unless
+        overridden individually, for example with the
+        <varname>TimerSlackNSec=</varname> setting in service units
+        (for details see
+        <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
+        The timer slack controls the accuracy of wake-ups triggered by
+        system timers. See
+        <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+        for more information. Note that in contrast to most other time
+        span definitions this parameter takes an integer value in
+        nano-seconds if no unit is specified. The usual time units are
+        understood too.</para>
+
+        <xi:include href="version-info.xml" xpointer="v198"/></listitem>
+      </varlistentry>
+      <varlistentry>
         <term><varname>CPUAffinity=</varname></term>
 
         <listitem><para>Configures the CPU affinity for the service manager as well as the default CPU
@@ -144,6 +201,142 @@
       </varlistentry>
 
       <varlistentry>
+        <term><varname>DefaultCPUAccounting=</varname></term>
+        <term><varname>DefaultMemoryAccounting=</varname></term>
+        <term><varname>DefaultTasksAccounting=</varname></term>
+        <term><varname>DefaultIOAccounting=</varname></term>
+        <term><varname>DefaultIPAccounting=</varname></term>
+
+        <listitem>
+        <para>Configure the default resource accounting settings, as configured per-unit by
+        <varname>CPUAccounting=</varname>, <varname>MemoryAccounting=</varname>,
+        <varname>TasksAccounting=</varname>, <varname>IOAccounting=</varname> and
+        <varname>IPAccounting=</varname>. See
+        <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        for details on the per-unit settings.</para>
+
+        <para><varname>DefaultCPUAccounting=</varname> defaults to yes when running on kernel ≥4.15, and no on older versions.
+        <varname>DefaultMemoryAccounting=</varname> defaults to &MEMORY_ACCOUNTING_DEFAULT;.
+        <varname>DefaultTasksAccounting=</varname> defaults to yes.
+        The other settings default to no.</para>
+
+        <xi:include href="version-info.xml" xpointer="v211"/>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>DefaultTasksMax=</varname></term>
+
+        <listitem><para>Configure the default value for the per-unit <varname>TasksMax=</varname> setting. See
+        <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        for details. This setting applies to all unit types that support resource control settings, with the exception
+        of slice units. Defaults to 15% of the minimum of <varname>kernel.pid_max=</varname>, <varname>kernel.threads-max=</varname>
+        and root cgroup <varname>pids.max</varname>.
+        Kernel has a default value for <varname>kernel.pid_max=</varname> and an algorithm of counting in case of more than 32 cores.
+        For example, with the default <varname>kernel.pid_max=</varname>, <varname>DefaultTasksMax=</varname> defaults to 4915,
+        but might be greater in other systems or smaller in OS containers.</para>
+
+        <xi:include href="version-info.xml" xpointer="v228"/></listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>DefaultLimitCPU=</varname></term>
+        <term><varname>DefaultLimitFSIZE=</varname></term>
+        <term><varname>DefaultLimitDATA=</varname></term>
+        <term><varname>DefaultLimitSTACK=</varname></term>
+        <term><varname>DefaultLimitCORE=</varname></term>
+        <term><varname>DefaultLimitRSS=</varname></term>
+        <term><varname>DefaultLimitNOFILE=</varname></term>
+        <term><varname>DefaultLimitAS=</varname></term>
+        <term><varname>DefaultLimitNPROC=</varname></term>
+        <term><varname>DefaultLimitMEMLOCK=</varname></term>
+        <term><varname>DefaultLimitLOCKS=</varname></term>
+        <term><varname>DefaultLimitSIGPENDING=</varname></term>
+        <term><varname>DefaultLimitMSGQUEUE=</varname></term>
+        <term><varname>DefaultLimitNICE=</varname></term>
+        <term><varname>DefaultLimitRTPRIO=</varname></term>
+        <term><varname>DefaultLimitRTTIME=</varname></term>
+
+        <listitem><para>These settings control various default resource limits for processes executed by
+        units. See
+        <citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry> for
+        details. These settings may be overridden in individual units using the corresponding
+        <varname>LimitXXX=</varname> directives and they accept the same parameter syntax,
+        see <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        for details. Note that these resource limits are only defaults
+        for units, they are not applied to the service manager process (i.e. PID 1) itself.</para>
+
+        <para>Most of these settings are unset, which means the resource limits are inherited from the kernel or, if
+        invoked in a container, from the container manager. However, the following have defaults:</para>
+        <itemizedlist>
+          <listitem><para><varname>DefaultLimitNOFILE=</varname> defaults to 1024:&HIGH_RLIMIT_NOFILE;.
+          </para></listitem>
+
+          <listitem><para><varname>DefaultLimitMEMLOCK=</varname> defaults to 8M.</para></listitem>
+
+          <listitem><para><varname>DefaultLimitCORE=</varname> does not have a default but it is worth mentioning that
+          <varname>RLIMIT_CORE</varname> is set to <literal>infinity</literal> by PID 1 which is inherited by its
+          children.</para></listitem>
+        </itemizedlist>
+
+        <para>Note that the service manager internally in PID 1 bumps <varname>RLIMIT_NOFILE</varname> and
+        <varname>RLIMIT_MEMLOCK</varname> to higher values, however the limit is reverted to the mentioned
+        defaults for all child processes forked off.</para>
+
+        <xi:include href="version-info.xml" xpointer="v198"/>
+      </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>DefaultOOMPolicy=</varname></term>
+
+        <listitem><para>Configure the default policy for reacting to processes being killed by the Linux
+        Out-Of-Memory (OOM) killer or <command>systemd-oomd</command>. This may be used to pick a global default for the per-unit
+        <varname>OOMPolicy=</varname> setting. See
+        <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        for details. Note that this default is not used for services that have <varname>Delegate=</varname>
+        turned on.</para>
+
+        <xi:include href="version-info.xml" xpointer="v243"/></listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>DefaultOOMScoreAdjust=</varname></term>
+
+        <listitem><para>Configures the default OOM score adjustments of processes run by the service
+        manager. This defaults to unset (meaning the forked off processes inherit the service manager's OOM
+        score adjustment value), except if the service manager is run for an unprivileged user, in which case
+        this defaults to the service manager's OOM adjustment value plus 100 (this makes service processes
+        slightly more likely to be killed under memory pressure than the manager itself). This may be used to
+        pick a global default for the per-unit <varname>OOMScoreAdjust=</varname> setting. See
+        <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
+        details. Note that this setting has no effect on the OOM score adjustment value of the service
+        manager process itself, it retains the original value set during its invocation.</para>
+
+        <xi:include href="version-info.xml" xpointer="v250"/></listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><varname>DefaultMemoryPressureWatch=</varname></term>
+        <term><varname>DefaultMemoryPressureThresholdSec=</varname></term>
+
+        <listitem><para>Configures the default settings for the per-unit
+        <varname>MemoryPressureWatch=</varname> and <varname>MemoryPressureThresholdSec=</varname>
+        settings. See
+        <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        for details. Defaults to <literal>auto</literal> and <literal>200ms</literal>, respectively. This
+        also sets the memory pressure monitoring threshold for the service manager itself.</para>
+
+        <xi:include href="version-info.xml" xpointer="v254"/></listitem>
+      </varlistentry>
+    </variablelist>
+  </refsect1>
+
+  <refsect1>
+    <title>Hardware Watchdog</title>
+
+    <variablelist class='config-directives'>
+      <varlistentry>
         <term><varname>RuntimeWatchdogSec=</varname></term>
         <term><varname>RebootWatchdogSec=</varname></term>
         <term><varname>KExecWatchdogSec=</varname></term>
@@ -252,7 +445,13 @@
 
         <xi:include href="version-info.xml" xpointer="v236"/></listitem>
       </varlistentry>
+    </variablelist>
+  </refsect1>
 
+  <refsect1>
+    <title>Security</title>
+
+    <variablelist class='config-directives'>
       <varlistentry>
         <term><varname>CapabilityBoundingSet=</varname></term>
 
@@ -339,59 +538,25 @@
       </varlistentry>
 
       <varlistentry>
-        <term><varname>TimerSlackNSec=</varname></term>
-
-        <listitem><para>Sets the timer slack in nanoseconds for PID 1,
-        which is inherited by all executed processes, unless
-        overridden individually, for example with the
-        <varname>TimerSlackNSec=</varname> setting in service units
-        (for details see
-        <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
-        The timer slack controls the accuracy of wake-ups triggered by
-        system timers. See
-        <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
-        for more information. Note that in contrast to most other time
-        span definitions this parameter takes an integer value in
-        nano-seconds if no unit is specified. The usual time units are
-        understood too.</para>
-
-        <xi:include href="version-info.xml" xpointer="v198"/></listitem>
-      </varlistentry>
-
-      <varlistentry>
-        <term><varname>StatusUnitFormat=</varname></term>
+        <term><varname>DefaultSmackProcessLabel=</varname></term>
 
-        <listitem><para>Takes <option>name</option>, <option>description</option> or
-        <option>combined</option> as the value. If <option>name</option>, the system manager will use unit
-        names in status messages (e.g. <literal>systemd-journald.service</literal>), instead of the longer
-        and more informative descriptions set with <varname>Description=</varname> (e.g. <literal>Journal
-        Logging Service</literal>). If <option>combined</option>, the system manager will use both unit names
-        and descriptions in status messages (e.g. <literal>systemd-journald.service - Journal Logging
-        Service</literal>).</para>
+        <listitem><para>Takes a <option>SMACK64</option> security label as the argument. The process executed
+        by a unit will be started under this label if <varname>SmackProcessLabel=</varname> is not set in the
+        unit. See <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+        for the details.</para>
 
-        <para>See
-        <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
-        details about unit names and <varname>Description=</varname>.</para>
+        <para>If the value is <literal>/</literal>, only labels specified with <varname>SmackProcessLabel=</varname>
+        are assigned and the compile-time default is ignored.</para>
 
-        <xi:include href="version-info.xml" xpointer="v243"/></listitem>
+        <xi:include href="version-info.xml" xpointer="v252"/></listitem>
       </varlistentry>
+    </variablelist>
+  </refsect1>
 
-      <varlistentry>
-        <term><varname>DefaultTimerAccuracySec=</varname></term>
-
-        <listitem><para>Sets the default accuracy of timer units. This
-        controls the global default for the
-        <varname>AccuracySec=</varname> setting of timer units, see
-        <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        for details. <varname>AccuracySec=</varname> set in individual
-        units override the global default for the specific unit.
-        Defaults to 1min. Note that the accuracy of timer units is
-        also affected by the configured timer slack for PID 1, see
-        <varname>TimerSlackNSec=</varname> above.</para>
-
-        <xi:include href="version-info.xml" xpointer="v212"/></listitem>
-      </varlistentry>
+  <refsect1>
+    <title>Timeouts and Rate Limits</title>
 
+    <variablelist class='config-directives'>
       <varlistentry>
         <term><varname>DefaultTimeoutStartSec=</varname></term>
         <term><varname>DefaultTimeoutStopSec=</varname></term>
@@ -448,28 +613,25 @@
       </varlistentry>
 
       <varlistentry>
-        <term><varname>DefaultEnvironment=</varname></term>
-
-        <listitem><para>Configures environment variables passed to all executed processes. Takes a
-        space-separated list of variable assignments. See <citerefentry
-        project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry> for
-        details about environment variables.</para>
-
-        <para>Simple <literal>%</literal>-specifier expansion is supported, see below for a list of supported
-        specifiers.</para>
-
-        <para>Example:
-
-        <programlisting>DefaultEnvironment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6"</programlisting>
+        <term><varname>ReloadLimitIntervalSec=</varname></term>
+        <term><varname>ReloadLimitBurst=</varname></term>
 
-        Sets three variables
-        <literal>VAR1</literal>,
-        <literal>VAR2</literal>,
-        <literal>VAR3</literal>.</para>
+        <listitem><para>Rate limiting for daemon-reload and (since v256) daemon-reexec requests. The setting
+        applies to both operations, but the rate limits are tracked separately. Defaults to unset, and any
+        number of operations can be requested at any time. <varname>ReloadLimitIntervalSec=</varname> takes
+        a value in seconds to configure the rate limit window, and <varname>ReloadLimitBurst=</varname>
+        takes a positive integer to configure the maximum allowed number of operations within the configured
+        time window.</para>
 
-        <xi:include href="version-info.xml" xpointer="v205"/></listitem>
+        <xi:include href="version-info.xml" xpointer="v253"/></listitem>
       </varlistentry>
+    </variablelist>
+  </refsect1>
 
+  <refsect1>
+    <title>Environment</title>
+
+    <variablelist class='config-directives'>
       <varlistentry>
         <term><varname>ManagerEnvironment=</varname></term>
 
@@ -493,161 +655,26 @@
       </varlistentry>
 
       <varlistentry>
-        <term><varname>DefaultCPUAccounting=</varname></term>
-        <term><varname>DefaultMemoryAccounting=</varname></term>
-        <term><varname>DefaultTasksAccounting=</varname></term>
-        <term><varname>DefaultIOAccounting=</varname></term>
-        <term><varname>DefaultIPAccounting=</varname></term>
-
-        <listitem>
-        <para>Configure the default resource accounting settings, as configured per-unit by
-        <varname>CPUAccounting=</varname>, <varname>MemoryAccounting=</varname>,
-        <varname>TasksAccounting=</varname>, <varname>IOAccounting=</varname> and
-        <varname>IPAccounting=</varname>. See
-        <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        for details on the per-unit settings.</para>
-
-        <para><varname>DefaultCPUAccounting=</varname> defaults to yes when running on kernel ≥4.15, and no on older versions.
-        <varname>DefaultMemoryAccounting=</varname> defaults to &MEMORY_ACCOUNTING_DEFAULT;.
-        <varname>DefaultTasksAccounting=</varname> defaults to yes.
-        The other settings default to no.</para>
-
-        <xi:include href="version-info.xml" xpointer="v211"/>
-        </listitem>
-      </varlistentry>
-
-      <varlistentry>
-        <term><varname>DefaultTasksMax=</varname></term>
-
-        <listitem><para>Configure the default value for the per-unit <varname>TasksMax=</varname> setting. See
-        <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        for details. This setting applies to all unit types that support resource control settings, with the exception
-        of slice units. Defaults to 15% of the minimum of <varname>kernel.pid_max=</varname>, <varname>kernel.threads-max=</varname>
-        and root cgroup <varname>pids.max</varname>.
-        Kernel has a default value for <varname>kernel.pid_max=</varname> and an algorithm of counting in case of more than 32 cores.
-        For example, with the default <varname>kernel.pid_max=</varname>, <varname>DefaultTasksMax=</varname> defaults to 4915,
-        but might be greater in other systems or smaller in OS containers.</para>
-
-        <xi:include href="version-info.xml" xpointer="v228"/></listitem>
-      </varlistentry>
-
-      <varlistentry>
-        <term><varname>DefaultLimitCPU=</varname></term>
-        <term><varname>DefaultLimitFSIZE=</varname></term>
-        <term><varname>DefaultLimitDATA=</varname></term>
-        <term><varname>DefaultLimitSTACK=</varname></term>
-        <term><varname>DefaultLimitCORE=</varname></term>
-        <term><varname>DefaultLimitRSS=</varname></term>
-        <term><varname>DefaultLimitNOFILE=</varname></term>
-        <term><varname>DefaultLimitAS=</varname></term>
-        <term><varname>DefaultLimitNPROC=</varname></term>
-        <term><varname>DefaultLimitMEMLOCK=</varname></term>
-        <term><varname>DefaultLimitLOCKS=</varname></term>
-        <term><varname>DefaultLimitSIGPENDING=</varname></term>
-        <term><varname>DefaultLimitMSGQUEUE=</varname></term>
-        <term><varname>DefaultLimitNICE=</varname></term>
-        <term><varname>DefaultLimitRTPRIO=</varname></term>
-        <term><varname>DefaultLimitRTTIME=</varname></term>
-
-        <listitem><para>These settings control various default resource limits for processes executed by
-        units. See
-        <citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry> for
-        details. These settings may be overridden in individual units using the corresponding
-        <varname>LimitXXX=</varname> directives and they accept the same parameter syntax,
-        see <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        for details. Note that these resource limits are only defaults
-        for units, they are not applied to the service manager process (i.e. PID 1) itself.</para>
-
-        <para>Most of these settings are unset, which means the resource limits are inherited from the kernel or, if
-        invoked in a container, from the container manager. However, the following have defaults:</para>
-        <itemizedlist>
-          <listitem><para><varname>DefaultLimitNOFILE=</varname> defaults to 1024:&HIGH_RLIMIT_NOFILE;.
-          </para></listitem>
-
-          <listitem><para><varname>DefaultLimitMEMLOCK=</varname> defaults to 8M.</para></listitem>
-
-          <listitem><para><varname>DefaultLimitCORE=</varname> does not have a default but it is worth mentioning that
-          <varname>RLIMIT_CORE</varname> is set to <literal>infinity</literal> by PID 1 which is inherited by its
-          children.</para></listitem>
-        </itemizedlist>
-
-        <para>Note that the service manager internally in PID 1 bumps <varname>RLIMIT_NOFILE</varname> and
-        <varname>RLIMIT_MEMLOCK</varname> to higher values, however the limit is reverted to the mentioned
-        defaults for all child processes forked off.</para>
-
-        <xi:include href="version-info.xml" xpointer="v198"/>
-      </listitem>
-      </varlistentry>
-
-      <varlistentry>
-        <term><varname>DefaultOOMPolicy=</varname></term>
-
-        <listitem><para>Configure the default policy for reacting to processes being killed by the Linux
-        Out-Of-Memory (OOM) killer or <command>systemd-oomd</command>. This may be used to pick a global default for the per-unit
-        <varname>OOMPolicy=</varname> setting. See
-        <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        for details. Note that this default is not used for services that have <varname>Delegate=</varname>
-        turned on.</para>
-
-        <xi:include href="version-info.xml" xpointer="v243"/></listitem>
-      </varlistentry>
-
-      <varlistentry>
-        <term><varname>DefaultOOMScoreAdjust=</varname></term>
-
-        <listitem><para>Configures the default OOM score adjustments of processes run by the service
-        manager. This defaults to unset (meaning the forked off processes inherit the service manager's OOM
-        score adjustment value), except if the service manager is run for an unprivileged user, in which case
-        this defaults to the service manager's OOM adjustment value plus 100 (this makes service processes
-        slightly more likely to be killed under memory pressure than the manager itself). This may be used to
-        pick a global default for the per-unit <varname>OOMScoreAdjust=</varname> setting. See
-        <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
-        details. Note that this setting has no effect on the OOM score adjustment value of the service
-        manager process itself, it retains the original value set during its invocation.</para>
-
-        <xi:include href="version-info.xml" xpointer="v250"/></listitem>
-      </varlistentry>
-
-      <varlistentry>
-        <term><varname>DefaultSmackProcessLabel=</varname></term>
-
-        <listitem><para>Takes a <option>SMACK64</option> security label as the argument. The process executed
-        by a unit will be started under this label if <varname>SmackProcessLabel=</varname> is not set in the
-        unit. See <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        for the details.</para>
-
-        <para>If the value is <literal>/</literal>, only labels specified with <varname>SmackProcessLabel=</varname>
-        are assigned and the compile-time default is ignored.</para>
-
-        <xi:include href="version-info.xml" xpointer="v252"/></listitem>
-      </varlistentry>
+        <term><varname>DefaultEnvironment=</varname></term>
 
-      <varlistentry>
-        <term><varname>ReloadLimitIntervalSec=</varname></term>
-        <term><varname>ReloadLimitBurst=</varname></term>
+        <listitem><para>Configures environment variables passed to all executed processes. Takes a
+        space-separated list of variable assignments. See <citerefentry
+        project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry> for
+        details about environment variables.</para>
 
-        <listitem><para>Rate limiting for daemon-reload and (since v256) daemon-reexec requests. The setting
-        applies to both operations, but the rate limits are tracked separately. Defaults to unset, and any
-        number of operations can be requested at any time. <varname>ReloadLimitIntervalSec=</varname> takes
-        a value in seconds to configure the rate limit window, and <varname>ReloadLimitBurst=</varname>
-        takes a positive integer to configure the maximum allowed number of operations within the configured
-        time window.</para>
+        <para>Simple <literal>%</literal>-specifier expansion is supported, see below for a list of supported
+        specifiers.</para>
 
-        <xi:include href="version-info.xml" xpointer="v253"/></listitem>
-      </varlistentry>
+        <para>Example:
 
-      <varlistentry>
-        <term><varname>DefaultMemoryPressureWatch=</varname></term>
-        <term><varname>DefaultMemoryPressureThresholdSec=</varname></term>
+        <programlisting>DefaultEnvironment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6"</programlisting>
 
-        <listitem><para>Configures the default settings for the per-unit
-        <varname>MemoryPressureWatch=</varname> and <varname>MemoryPressureThresholdSec=</varname>
-        settings. See
-        <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-        for details. Defaults to <literal>auto</literal> and <literal>200ms</literal>, respectively. This
-        also sets the memory pressure monitoring threshold for the service manager itself.</para>
+        Sets three variables
+        <literal>VAR1</literal>,
+        <literal>VAR2</literal>,
+        <literal>VAR3</literal>.</para>
 
-        <xi:include href="version-info.xml" xpointer="v254"/></listitem>
+        <xi:include href="version-info.xml" xpointer="v205"/></listitem>
       </varlistentry>
     </variablelist>
   </refsect1>