hashmap: add OrderedHashmap as a distinct type

[elogind.git] / man / systemd.timer.xml

diff --git a/man/systemd.timer.xml b/man/systemd.timer.xml
index 9b6b486bf43f353dac6f52af7a0ec111a55f7c57..55b458557f357634ae7f27591cbd8cddf7001e30 100644 (file)
--- a/man/systemd.timer.xml
+++ b/man/systemd.timer.xml
@@ -9,16 +9,16 @@
   Copyright 2010 Lennart Poettering
 
   systemd is free software; you can redistribute it and/or modify it
   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
   (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/>.
 -->
 
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 -->
 


@@ -44,18 +44,18 @@
 
         <refnamediv>
                 <refname>systemd.timer</refname>
 
         <refnamediv>
                 <refname>systemd.timer</refname>

-                <refpurpose>systemd timer configuration files</refpurpose>
+                <refpurpose>Timer unit configuration</refpurpose>

         </refnamediv>
 
         <refsynopsisdiv>
         </refnamediv>
 
         <refsynopsisdiv>

-                <para><filename>systemd.timer</filename></para>
+                <para><filename><replaceable>timer</replaceable>.timer</filename></para>

         </refsynopsisdiv>
 
         <refsect1>
                 <title>Description</title>
 
                 <para>A unit configuration file whose name ends in
         </refsynopsisdiv>
 
         <refsect1>
                 <title>Description</title>
 
                 <para>A unit configuration file whose name ends in

-                <filename>.timer</filename> encodes information about
+                <literal>.timer</literal> encodes information about

                 a timer controlled and supervised by systemd, for
                 timer-based activation.</para>
 
                 a timer controlled and supervised by systemd, for
                 timer-based activation.</para>
 


@@ -78,15 +78,20 @@
                 <varname>Unit=</varname> (see below).</para>
 
                 <para>Unless <varname>DefaultDependencies=</varname>
                 <varname>Unit=</varname> (see below).</para>
 
                 <para>Unless <varname>DefaultDependencies=</varname>

-                is set to <option>false</option>, timer units will
+                is set to <option>false</option>, all timer units will

                 implicitly have dependencies of type
                 <varname>Conflicts=</varname> and
                 <varname>Before=</varname> on
                 implicitly have dependencies of type
                 <varname>Conflicts=</varname> and
                 <varname>Before=</varname> on

-                <filename>shutdown.target</filename>. These ensure
-                that timer units are stopped cleanly prior to system
-                shutdown. Only timer units involved with early boot or
-                late system shutdown should disable this
-                option.</para>
+                <filename>shutdown.target</filename> to ensure that
+                they are stopped cleanly prior to system shutdown.
+                Timer units with at least one
+                <varname>OnCalendar=</varname> directive will have an
+                additional <varname>After=</varname> dependency on
+                <filename>timer-sync.target</filename> to avoid
+                being started before the system clock has been
+                correctly set. Only timer units involved with early
+                boot or late system shutdown should disable the
+                <varname>DefaultDependencies=</varname> option.</para>

         </refsect1>
 
         <refsect1>
         </refsect1>
 
         <refsect1>


@@ -97,7 +102,7 @@
                 defines. The options specific to the [Timer] section
                 of timer units are the following:</para>
 
                 defines. The options specific to the [Timer] section
                 of timer units are the following:</para>
 

-                <variablelist>
+                <variablelist class='unit-directives'>

                         <varlistentry>
                                 <term><varname>OnActiveSec=</varname></term>
                                 <term><varname>OnBootSec=</varname></term>
                         <varlistentry>
                                 <term><varname>OnActiveSec=</varname></term>
                                 <term><varname>OnBootSec=</varname></term>


@@ -105,7 +110,7 @@
                                 <term><varname>OnUnitActiveSec=</varname></term>
                                 <term><varname>OnUnitInactiveSec=</varname></term>
 
                                 <term><varname>OnUnitActiveSec=</varname></term>
                                 <term><varname>OnUnitInactiveSec=</varname></term>
 

-                                <listitem><para>Defines timers
+                                <listitem><para>Defines monotonic timers

                                 relative to different starting points:
                                 <varname>OnActiveSec=</varname> defines a
                                 timer relative to the moment the timer
                                 relative to different starting points:
                                 <varname>OnActiveSec=</varname> defines a
                                 timer relative to the moment the timer


@@ -115,7 +120,7 @@
                                 machine was booted
                                 up. <varname>OnStartupSec=</varname>
                                 defines a timer relative to when
                                 machine was booted
                                 up. <varname>OnStartupSec=</varname>
                                 defines a timer relative to when

-                                systemd was
+                                systemd was first

                                 started. <varname>OnUnitActiveSec=</varname>
                                 defines a timer relative to when the
                                 unit the timer is activating was last
                                 started. <varname>OnUnitActiveSec=</varname>
                                 defines a timer relative to when the
                                 unit the timer is activating was last


@@ -128,7 +133,7 @@
                                 combined of the same and of different
                                 types. For example, by combining
                                 <varname>OnBootSec=</varname> and
                                 combined of the same and of different
                                 types. For example, by combining
                                 <varname>OnBootSec=</varname> and

-                                <varname>OnUnitActiveSec=</varname> it is
+                                <varname>OnUnitActiveSec=</varname>, it is

                                 possible to define a timer that
                                 elapses in regular intervals and
                                 activates a specific service each
                                 possible to define a timer that
                                 elapses in regular intervals and
                                 activates a specific service each


@@ -139,9 +144,9 @@
                                 seconds. Example: "OnBootSec=50" means
                                 50s after boot-up. The argument may
                                 also include time units. Example:
                                 seconds. Example: "OnBootSec=50" means
                                 50s after boot-up. The argument may
                                 also include time units. Example:

-                                "OnBootSec=5h 30min" means 5 hours and 30
-                                minutes after boot-up. For details
-                                about the syntax of time spans see
+                                "OnBootSec=5h 30min" means 5 hours and
+                                30 minutes after boot-up. For details
+                                about the syntax of time spans, see

                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
 
                                 <para>If a timer configured with
                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
 
                                 <para>If a timer configured with


@@ -152,13 +157,86 @@
                                 elapse and the configured unit is
                                 started. This is not the case for
                                 timers defined in the other
                                 elapse and the configured unit is
                                 started. This is not the case for
                                 timers defined in the other

-                                directives.</para></listitem>
+                                directives.</para>

 
                                 <para>These are monotonic timers,
                                 independent of wall-clock time and timezones. If the
                                 computer is temporarily suspended, the
                                 monotonic clock stops too.</para>
 
 
                                 <para>These are monotonic timers,
                                 independent of wall-clock time and timezones. If the
                                 computer is temporarily suspended, the
                                 monotonic clock stops too.</para>
 

+                                <para>If the empty string is assigned
+                                to any of these options, the list of
+                                timers is reset, and all prior
+                                assignments will have no
+                                effect.</para>
+
+                                <para>Note that timers do not
+                                necessarily expire at the precise
+                                time configured with these settings,
+                                as they are subject to the
+                                <varname>AccuracySec=</varname>
+                                setting below.</para></listitem>
+
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><varname>OnCalendar=</varname></term>
+
+                                <listitem><para>Defines realtime
+                                (i.e. wallclock) timers with calendar
+                                event expressions. See
+                                <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+                                for more information on the syntax of
+                                calendar event expressions. Otherwise,
+                                the semantics are similar to
+                                <varname>OnActiveSec=</varname> and
+                                related settings.</para>
+
+                                <para>Note that timers do not
+                                necessarily expire at the precise
+                                time configured with this setting,
+                                as it is subject to the
+                                <varname>AccuracySec=</varname>
+                                setting below.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><varname>AccuracySec=</varname></term>
+
+                                <listitem><para>Specify the accuracy
+                                the timer shall elapse with. Defaults
+                                to 1min. The timer is scheduled to
+                                elapse within a time window starting
+                                with the time specified in
+                                <varname>OnCalendar=</varname>,
+                                <varname>OnActiveSec=</varname>,
+                                <varname>OnBootSec=</varname>,
+                                <varname>OnStartupSec=</varname>,
+                                <varname>OnUnitActiveSec=</varname> or
+                                <varname>OnUnitInactiveSec=</varname>
+                                and ending the time configured with
+                                <varname>AccuracySec=</varname>
+                                later. Within this time window, the
+                                expiry time will be placed at a
+                                host-specific, randomized but stable
+                                position that is synchronized between
+                                all local timer units. This is done in
+                                order to distribute the wake-up time
+                                in networked installations, as well as
+                                optimizing power consumption to
+                                suppress unnecessary CPU wake-ups. To
+                                get best accuracy, set this option to
+                                1us. Note that the timer is still
+                                subject to the timer slack configured
+                                via
+                                <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>'s
+                                <varname>TimerSlackNSec=</varname>
+                                setting. See
+                                <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+                                for details. To optimize power
+                                consumption, make sure to set this
+                                value as high as possible and as low
+                                as necessary.</para></listitem>

                         </varlistentry>
                         <varlistentry>
                                 <term><varname>Unit=</varname></term>
                         </varlistentry>
                         <varlistentry>
                                 <term><varname>Unit=</varname></term>


@@ -166,7 +244,7 @@
                                 <listitem><para>The unit to activate
                                 when this timer elapses. The argument is a
                                 unit name, whose suffix is not
                                 <listitem><para>The unit to activate
                                 when this timer elapses. The argument is a
                                 unit name, whose suffix is not

-                                <filename>.timer</filename>. If not
+                                <literal>.timer</literal>. If not

                                 specified, this value defaults to a
                                 service that has the same name as the
                                 timer unit, except for the
                                 specified, this value defaults to a
                                 service that has the same name as the
                                 timer unit, except for the


@@ -176,6 +254,43 @@
                                 are named identically, except for the
                                 suffix.</para></listitem>
                         </varlistentry>
                                 are named identically, except for the
                                 suffix.</para></listitem>
                         </varlistentry>

+
+
+                        <varlistentry>
+                                <term><varname>Persistent=</varname></term>
+
+                                <listitem><para>Takes a boolean
+                                argument. If true, the time when the
+                                service unit was last triggered is
+                                stored on disk. When the timer is
+                                activated, the service unit is
+                                triggered immediately if it would have
+                                been triggered at least once during
+                                the time when the timer was inactive.
+                                This is useful to catch up on missed
+                                runs of the service when the machine
+                                was off. Note that this setting only
+                                has an effect on timers configured
+                                with <varname>OnCalendar=</varname>.
+                                </para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><varname>WakeSystem=</varname></term>
+
+                                <listitem><para>Takes a boolean
+                                argument. If true, an elapsing timer
+                                will cause the system to resume from
+                                suspend, should it be suspended and if
+                                the system supports this. Note that
+                                this option will only make sure the
+                                system resumes on the appropriate
+                                times, it will not take care of
+                                suspending it again after any work
+                                that is to be done is
+                                finished. Defaults to
+                                <varname>false</varname>.</para></listitem>
+                        </varlistentry>

                 </variablelist>
         </refsect1>
 
                 </variablelist>
         </refsect1>
 


@@ -183,9 +298,13 @@
                   <title>See Also</title>
                   <para>
                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                   <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.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

-                          <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                          <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>

                   </para>
         </refsect1>
 
                   </para>
         </refsect1>