From f535af6bcd51a5c25b6c8a3b8004f38ca84f1adf Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Thu, 16 Jan 2020 19:40:51 +0100 Subject: [PATCH] man: document that WakeSystem= affects clock choice Fixes: #8308 --- man/systemd.timer.xml | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/man/systemd.timer.xml b/man/systemd.timer.xml index fca11b2d04c..040b8e28939 100644 --- a/man/systemd.timer.xml +++ b/man/systemd.timer.xml @@ -163,7 +163,10 @@ timers defined in the other directives. These are monotonic timers, independent of wall-clock time and timezones. If the computer is - temporarily suspended, the monotonic clock pauses, too. + temporarily suspended, the monotonic clock generally pauses, too. Note that if + WakeSystem= is used, a different monotonic clock is selected that continues to + advance while the system is suspended and thus can be used as the trigger to resume the + system. If the empty string is assigned to any of these options, the list of timers is reset (both monotonic timers and OnCalendar= timers, see below), and all prior assignments @@ -316,7 +319,16 @@ false. Note that this functionality requires privileges and is thus generally only available in the - system service manager. + system service manager. + + Note that behaviour of monotonic clock timers (as configured with + OnActiveSec=, OnBootSec=, OnStartupSec=, + OnUnitActiveSec=, OnUnitInactiveSec=, see above) is altered + depending on this option. If false, a monotonic clock is used that is paused during system suspend + (CLOCK_MONOTONIC), if true a different monotonic clock is used that continues + advancing during system suspend (CLOCK_BOOTTIME), see + clock_getres2 for + details. -- 2.39.2