systemd-sleep.conf(5) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | CONFIGURATION DIRECTORIES AND PRECEDENCE | OPTIONS | EXAMPLE: FREEZE | SEE ALSO | COLOPHON

SYSTEMD-SLEEP.CONF(5)      systemd-sleep.conf      SYSTEMD-SLEEP.CONF(5)

NAME         top

       systemd-sleep.conf, sleep.conf.d - Suspend and hibernation
       configuration file

SYNOPSIS         top

       /etc/systemd/sleep.conf

       /etc/systemd/sleep.conf.d/*.conf

       /run/systemd/sleep.conf.d/*.conf

       /usr/lib/systemd/sleep.conf.d/*.conf

DESCRIPTION         top

       systemd supports four general power-saving modes:

       suspend
           a low-power state where execution of the OS is paused, and
           complete power loss might result in lost data, and which is
           fast to enter and exit. This corresponds to suspend, standby,
           or freeze states as understood by the kernel.

       hibernate
           a low-power state where execution of the OS is paused, and
           complete power loss does not result in lost data, and which
           might be slow to enter and exit. This corresponds to the
           hibernation as understood by the kernel.

       hybrid-sleep
           a low-power state where execution of the OS is paused, which
           might be slow to enter, and on complete power loss does not
           result in lost data but might be slower to exit in that case.
           This mode is called suspend-to-both by the kernel.

       suspend-then-hibernate
           A low power state where initially user.slice unit is freezed.
           If the hardware supports low-battery alarms (ACPI _BTP), then
           the system is first suspended (the state is stored in RAM)
           and then hibernates if the system is woken up by the hardware
           via ACPI low-battery signal. Unit user.slice is thawed when
           system returns from hibernation. If the hardware does not
           support low-battery alarms (ACPI _BTP), then the system is
           suspended based on battery's current percentage capacity. If
           the current battery capacity is higher than 5%, the system
           suspends for interval calculated using battery discharge rate
           per hour or HibernateDelaySec= if former is not available.
           Battery discharge rate per hour is stored in a file which is
           created after initial suspend-resume cycle. The value is
           calculated using battery decreasing charge level over a
           timespan for which system was suspended. For each battery
           connected to the system, there is a unique entry. After RTC
           alarm wakeup from suspend, battery discharge rate per hour is
           again estimated. If the current battery charge level is equal
           to or less than 5%, the system will be hibernated (the state
           is then stored on disk) else the system goes back to suspend
           for the interval calculated using battery discharge rate per
           hour. In case of manual wakeup, if the battery was discharged
           while the system was suspended, the battery discharge rate is
           estimated and stored on the filesystem. In case the system is
           woken up by the hardware via the ACPI low-battery signal,
           then it hibernates.

       Settings in these files determine what strings will be written to
       /sys/power/disk and /sys/power/state by systemd-sleep(8) when
       systemd(1) attempts to suspend or hibernate the machine. See
       systemd.syntax(7) for a general description of the syntax.

CONFIGURATION DIRECTORIES AND PRECEDENCE         top

       The default configuration is set during compilation, so
       configuration is only needed when it is necessary to deviate from
       those defaults. Initially, the main configuration file in
       /etc/systemd/ contains commented out entries showing the defaults
       as a guide to the administrator. Local overrides can be created
       by editing this file or by creating drop-ins, as described below.
       Using drop-ins for local configuration is recommended over
       modifications to the main configuration file.

       In addition to the "main" configuration file, drop-in
       configuration snippets are read from /usr/lib/systemd/*.conf.d/,
       /usr/local/lib/systemd/*.conf.d/, and /etc/systemd/*.conf.d/.
       Those drop-ins have higher precedence and override the main
       configuration file. Files in the *.conf.d/ configuration
       subdirectories are sorted by their filename in lexicographic
       order, regardless of in which of the subdirectories they reside.
       When multiple files specify the same option, for options which
       accept just a single value, the entry in the file sorted last
       takes precedence, and for options which accept a list of values,
       entries are collected as they occur in the sorted files.

       When packages need to customize the configuration, they can
       install drop-ins under /usr/. Files in /etc/ are reserved for the
       local administrator, who may use this logic to override the
       configuration files installed by vendor packages. Drop-ins have
       to be used to override package drop-ins, since the main
       configuration file has lower precedence. It is recommended to
       prefix all filenames in those subdirectories with a two-digit
       number and a dash, to simplify the ordering of the files.

       To disable a configuration file supplied by the vendor, the
       recommended way is to place a symlink to /dev/null in the
       configuration directory in /etc/, with the same filename as the
       vendor configuration file.

OPTIONS         top

       The following options can be configured in the [Sleep] section of
       /etc/systemd/sleep.conf or a sleep.conf.d file:

       AllowSuspend=, AllowHibernation=, AllowSuspendThenHibernate=,
       AllowHybridSleep=
           By default any power-saving mode is advertised if possible
           (i.e. the kernel supports that mode, the necessary resources
           are available). Those switches can be used to disable
           specific modes.

           If AllowHibernation=no or AllowSuspend=no is used, this
           implies AllowSuspendThenHibernate=no and AllowHybridSleep=no,
           since those methods use both suspend and hibernation
           internally.  AllowSuspendThenHibernate=yes and
           AllowHybridSleep=yes can be used to override and enable those
           specific modes.

       SuspendMode=, HibernateMode=, HybridSleepMode=
           The string to be written to /sys/power/disk by, respectively,
           systemd-suspend.service(8), systemd-hibernate.service(8), or
           systemd-hybrid-sleep.service(8). More than one value can be
           specified by separating multiple values with whitespace. They
           will be tried in turn, until one is written without error. If
           neither succeeds, the operation will be aborted.

           systemd-suspend-then-hibernate.service(8) uses the value of
           SuspendMode= when suspending and the value of HibernateMode=
           when hibernating.

       SuspendState=, HibernateState=, HybridSleepState=
           The string to be written to /sys/power/state by,
           respectively, systemd-suspend.service(8),
           systemd-hibernate.service(8), or
           systemd-hybrid-sleep.service(8). More than one value can be
           specified by separating multiple values with whitespace. They
           will be tried in turn, until one is written without error. If
           neither succeeds, the operation will be aborted.

           systemd-suspend-then-hibernate.service(8) uses the value of
           SuspendState= when suspending and the value of
           HibernateState= when hibernating.

       HibernateDelaySec=
           The amount of time the system spends in suspend mode before
           the RTC alarm wakes the system, before the battery discharge
           rate can be estimated and used instead to calculate the
           suspension interval.
           systemd-suspend-then-hibernate.service(8). Defaults to 2h.

EXAMPLE: FREEZE         top

       Example: to exploit the “freeze” mode added in Linux 3.9, one can
       use systemctl suspend with

           [Sleep]
           SuspendState=freeze

SEE ALSO         top

       systemd-sleep(8), systemd-suspend.service(8),
       systemd-hibernate.service(8), systemd-hybrid-sleep.service(8),
       systemd-suspend-then-hibernate.service(8), systemd(1),
       systemd.directives(7)

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have
       a bug report for this manual page, see
       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2022-12-17.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2022-12-16.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

systemd 252                                        SYSTEMD-SLEEP.CONF(5)

Pages that refer to this page: systemd.directives(7)systemd.index(7)systemd.syntax(7)systemd-suspend.service(8)