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diff --git a/man/systemd.timer.xml b/man/systemd.timer.xml deleted file mode 100644 index 4fe140e4bc..0000000000 --- a/man/systemd.timer.xml +++ /dev/null @@ -1,313 +0,0 @@ -<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*--> -<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" - "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> - -<!-- - This file is part of systemd. - - Copyright 2010 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. ---> - -<refentry id="systemd.timer"> - <refentryinfo> - <title>systemd.timer</title> - <productname>systemd</productname> - - <authorgroup> - <author> - <contrib>Developer</contrib> - <firstname>Lennart</firstname> - <surname>Poettering</surname> - <email>lennart@poettering.net</email> - </author> - </authorgroup> - </refentryinfo> - - <refmeta> - <refentrytitle>systemd.timer</refentrytitle> - <manvolnum>5</manvolnum> - </refmeta> - - <refnamediv> - <refname>systemd.timer</refname> - <refpurpose>Timer unit configuration</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <para><filename><replaceable>timer</replaceable>.timer</filename></para> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para>A unit configuration file whose name ends in - <literal>.timer</literal> encodes information about a timer - controlled and supervised by systemd, for timer-based - activation.</para> - - <para>This man page lists the configuration options specific to - this unit type. See - <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry> - for the common options of all unit configuration files. The common - configuration items are configured in the generic [Unit] and - [Install] sections. The timer specific configuration options are - configured in the [Timer] section.</para> - - <para>For each timer file, a matching unit file must exist, - describing the unit to activate when the timer elapses. By - default, a service by the same name as the timer (except for the - suffix) is activated. Example: a timer file - <filename>foo.timer</filename> activates a matching service - <filename>foo.service</filename>. The unit to activate may be - controlled by <varname>Unit=</varname> (see below).</para> - - <para>Note that in case the unit to activate is already active at the time the timer elapses it is not restarted, - but simply left running. There is no concept of spawning new service instances in this case. Due to this, services - with <varname>RemainAfterExit=</varname> set (which stay around continuously even after the service's main process - exited) are usually not suitable for activation via repetitive timers, as they will only be activated once, and - then stay around forever.</para> - </refsect1> - - <refsect1> - <title>Automatic Dependencies</title> - - <para>Timer units automatically gain a <varname>Before=</varname> - dependency on the service they are supposed to activate.</para> - - <para>Unless <varname>DefaultDependencies=</varname> in the <literal>[Unit]</literal> section is set to - <option>false</option>, all timer units will implicitly have dependencies of type <varname>Requires=</varname> and - <varname>After=</varname> on <filename>sysinit.target</filename>, a dependency of type <varname>Before=</varname> - on <filename>timers.target</filename>, as well as <varname>Conflicts=</varname> and <varname>Before=</varname> on - <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> - <title>Options</title> - - <para>Timer files must include a [Timer] section, which carries - information about the timer it defines. The options specific to - the [Timer] section of timer units are the following:</para> - - <variablelist class='unit-directives'> - <varlistentry> - <term><varname>OnActiveSec=</varname></term> - <term><varname>OnBootSec=</varname></term> - <term><varname>OnStartupSec=</varname></term> - <term><varname>OnUnitActiveSec=</varname></term> - <term><varname>OnUnitInactiveSec=</varname></term> - - <listitem><para>Defines monotonic timers relative to different - starting points: <varname>OnActiveSec=</varname> defines a - timer relative to the moment the timer itself is activated. - <varname>OnBootSec=</varname> defines a timer relative to when - the machine was booted up. <varname>OnStartupSec=</varname> - defines a timer relative to when systemd was first started. - <varname>OnUnitActiveSec=</varname> defines a timer relative - to when the unit the timer is activating was last activated. - <varname>OnUnitInactiveSec=</varname> defines a timer relative - to when the unit the timer is activating was last - deactivated.</para> - - <para>Multiple directives may be combined of the same and of - different types. For example, by combining - <varname>OnBootSec=</varname> and - <varname>OnUnitActiveSec=</varname>, it is possible to define - a timer that elapses in regular intervals and activates a - specific service each time.</para> - - <para>The arguments to the directives are time spans - configured in 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 - <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> - - <para>If a timer configured with <varname>OnBootSec=</varname> - or <varname>OnStartupSec=</varname> is already in the past - when the timer unit is activated, it will immediately elapse - and the configured unit is started. This is not the case for - timers defined in the other 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>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 optimize 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>RandomizedDelaySec=</varname></term> - - <listitem><para>Delay the timer by a randomly selected, evenly - distributed amount of time between 0 and the specified time - value. Defaults to 0, indicating that no randomized delay - shall be applied. Each timer unit will determine this delay - randomly each time it is started, and the delay will simply be - added on top of the next determined elapsing time. This is - useful to stretch dispatching of similarly configured timer - events over a certain amount time, to avoid that they all fire - at the same time, possibly resulting in resource - congestion. Note the relation to - <varname>AccuracySec=</varname> above: the latter allows the - service manager to coalesce timer events within a specified - time range in order to minimize wakeups, the former does the - opposite: it stretches timer events over a time range, to make - it unlikely that they fire simultaneously. If - <varname>RandomizedDelaySec=</varname> and - <varname>AccuracySec=</varname> are used in conjunction, first - the randomized delay is added, and then the result is - possibly further shifted to coalesce it with other timer - events happening on the system. As mentioned above - <varname>AccuracySec=</varname> defaults to 1min and - <varname>RandomizedDelaySec=</varname> to 0, thus encouraging - coalescing of timer events. In order to optimally stretch - timer events over a certain range of time, make sure to set - <varname>RandomizedDelaySec=</varname> to a higher value, and - <varname>AccuracySec=1us</varname>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>Unit=</varname></term> - - <listitem><para>The unit to activate when this timer elapses. - The argument is a unit name, whose suffix is 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 suffix. (See above.) It is recommended - that the unit name that is activated and the unit name of the - timer unit 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>. Defaults - to <varname>false</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> - - <varlistentry> - <term><varname>RemainAfterElapse=</varname></term> - - <listitem><para>Takes a boolean argument. If true, an elapsed - timer will stay loaded, and its state remains queriable. If - false, an elapsed timer unit that cannot elapse anymore is - unloaded. Turning this off is particularly useful for - transient timer units that shall disappear after they first - elapse. Note that this setting has an effect on repeatedly - starting a timer unit that only elapses once: if - <varname>RemainAfterElapse=</varname> is on, it will not be - started again, and is guaranteed to elapse only once. However, - if <varname>RemainAfterElapse=</varname> is off, it might be - started again if it is already elapsed, and thus be triggered - multiple times. Defaults to - <varname>yes</varname>.</para></listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>See Also</title> - <para> - <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.unit</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> - -</refentry> |