X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd.timer.xml;h=55b458557f357634ae7f27591cbd8cddf7001e30;hp=9b6b486bf43f353dac6f52af7a0ec111a55f7c57;hb=5ba43716f345e205eba33156c0171fb657f4451f;hpb=ad678a066b4ba5d8914dd7d5a4093572841205cf diff --git a/man/systemd.timer.xml b/man/systemd.timer.xml index 9b6b486bf..55b458557 100644 --- 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 - 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 . --> @@ -44,18 +44,18 @@ systemd.timer - systemd timer configuration files + Timer unit configuration - systemd.timer + timer.timer Description A unit configuration file whose name ends in - .timer encodes information about + .timer encodes information about a timer controlled and supervised by systemd, for timer-based activation. @@ -78,15 +78,20 @@ Unit= (see below). Unless DefaultDependencies= - is set to , timer units will + is set to , all timer units will implicitly have dependencies of type Conflicts= and Before= on - shutdown.target. 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. + shutdown.target to ensure that + they are stopped cleanly prior to system shutdown. + Timer units with at least one + OnCalendar= directive will have an + additional After= dependency on + timer-sync.target 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 + DefaultDependencies= option. @@ -97,7 +102,7 @@ defines. The options specific to the [Timer] section of timer units are the following: - + OnActiveSec= OnBootSec= @@ -105,7 +110,7 @@ OnUnitActiveSec= OnUnitInactiveSec= - Defines timers + Defines monotonic timers relative to different starting points: OnActiveSec= defines a timer relative to the moment the timer @@ -115,7 +120,7 @@ machine was booted up. OnStartupSec= defines a timer relative to when - systemd was + systemd was first started. OnUnitActiveSec= 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 OnBootSec= and - OnUnitActiveSec= it is + OnUnitActiveSec=, it is 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: - "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 systemd.unit5. 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 - directives. + directives. These are monotonic timers, independent of wall-clock time and timezones. If the computer is temporarily suspended, the monotonic clock stops too. + 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. + + Note that timers do not + necessarily expire at the precise + time configured with these settings, + as they are subject to the + AccuracySec= + setting below. + + + + + OnCalendar= + + Defines realtime + (i.e. wallclock) timers with calendar + event expressions. See + systemd.time7 + for more information on the syntax of + calendar event expressions. Otherwise, + the semantics are similar to + OnActiveSec= and + related settings. + + Note that timers do not + necessarily expire at the precise + time configured with this setting, + as it is subject to the + AccuracySec= + setting below. + + + + AccuracySec= + + 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 + OnCalendar=, + OnActiveSec=, + OnBootSec=, + OnStartupSec=, + OnUnitActiveSec= or + OnUnitInactiveSec= + and ending the time configured with + AccuracySec= + 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 + systemd-system.conf5's + TimerSlackNSec= + setting. See + prctl2 + for details. To optimize power + consumption, make sure to set this + value as high as possible and as low + as necessary. Unit= @@ -166,7 +244,7 @@ The unit to activate when this timer elapses. The argument is a unit name, whose suffix is not - .timer. If not + .timer. If not 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. + + + + Persistent= + + 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 OnCalendar=. + + + + + WakeSystem= + + 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 + false. + @@ -183,9 +298,13 @@ See Also systemd1, - systemctl8, + systemctl1, systemd.unit5, - systemd.service5 + systemd.service5, + systemd.time7, + systemd.directives7, + systemd-system.conf5, + prctl2