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diff --git a/man/systemd.timer.xml b/man/systemd.timer.xml
index e08e20021..55b458557 100644
--- a/man/systemd.timer.xml
+++ b/man/systemd.timer.xml
@@ -48,14 +48,14 @@
- systemd.timer
+ timer.timerDescriptionA 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=
@@ -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
@@ -141,7 +146,7 @@
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
+ about the syntax of time spans, see
systemd.unit5.
If a timer configured with
@@ -157,7 +162,20 @@
These are monotonic timers,
independent of wall-clock time and timezones. If the
computer is temporarily suspended, the
- monotonic clock stops too.
+ 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.
@@ -165,21 +183,68 @@
OnCalendar=Defines realtime
- (i.e. wallclock) timers via calendar
+ (i.e. wallclock) timers with calendar
event expressions. See
systemd.time7
for more information on the syntax of
- calendar event
- expressions.
+ 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=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
@@ -189,6 +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.
+
@@ -196,11 +298,13 @@