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

NAME | SYNOPSIS | DESCRIPTION | CONFIGURATION DIRECTORIES AND PRECEDENCE | OPTIONS | EXAMPLE: FREEZE | SEE ALSO | NOTES | 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
           /run/systemd/sleep.conf
           /usr/lib/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.

           Added in version 203.

       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.

           Added in version 203.

       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.

           Added in version 203.

       suspend-then-hibernate
           A low power state where the system is initially suspended
           (the state is stored in RAM). When the battery level is too
           low (less than 5%) or a certain timespan has passed,
           whichever happens first, the system is automatically woken up
           and then hibernated. This establishes a balance between speed
           and safety.

           If the system has no battery, it would be hibernated after
           HibernateDelaySec= has passed. If not set, then defaults to
           "2h".

           If the system has battery and HibernateDelaySec= is not set,
           low-battery alarms (ACPI _BTP) are tried first for detecting
           battery percentage and wake up the system for hibernation. If
           not available, or HibernateDelaySec= is set, the system would
           regularly wake up to check the time and detect the battery
           percentage/discharging rate. The rate is used to schedule the
           next detection. If that is also not available,
           SuspendEstimationSec= is used as last resort.

           Added in version 239.

       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. The main configuration file is loaded from one of
       the listed directories in order of priority, only the first file
       found is used: /etc/systemd/, /run/systemd/,
       /usr/local/lib/systemd/ [1], /usr/lib/systemd/. The vendor
       version of the file contains commented out entries showing the
       defaults as a guide to the administrator. Local overrides can
       also be created by creating drop-ins, as described below. The
       main configuration file can also be edited for this purpose (or a
       copy in /etc/ if it's shipped under /usr/), however 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. This also defines a
       concept of drop-in priorities to allow OS vendors to ship
       drop-ins within a specific range lower than the range used by
       users. This should lower the risk of package drop-ins overriding
       accidentally drop-ins defined by users. It is recommended to use
       the range 10-40 for drop-ins in /usr/ and the range 60-90 for
       drop-ins in /etc/ and /run/, to make sure that local and
       transient drop-ins take priority over drop-ins shipped by the OS
       vendor.

       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=, AllowHybridSleep=,
       AllowSuspendThenHibernate=
           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.

           Added in version 240.

       SuspendState=
           The string to be written to /sys/power/state by
           systemd-suspend.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
           none of the writes succeed, the operation will be aborted.

           The allowed set of values is determined by the kernel and is
           shown in the file itself (use cat /sys/power/state to
           display). See Basic sysfs Interfaces for System Suspend and
           Hibernation[2] for more details.

           systemd-suspend-then-hibernate.service(8) uses this value
           when suspending.

           Added in version 203.

       HibernateMode=
           The string to be written to /sys/power/disk by
           systemd-hibernate.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
           none of the writes succeed, the operation will be aborted.

           The allowed set of values is determined by the kernel and is
           shown in the file itself (use cat /sys/power/disk to
           display). See the kernel documentation page Basic sysfs
           Interfaces for System Suspend and Hibernation[2] for more
           details.

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

           Added in version 203.

       MemorySleepMode=
           The string to be written to /sys/power/mem_sleep when
           SuspendState=mem or hybrid-sleep is used. 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 none of the writes succeed, the operation
           will be aborted. Defaults to empty, i.e. the kernel default
           or kernel command line option mem_sleep_default= is
           respected.

           The allowed set of values is determined by the kernel and is
           shown in the file itself (use cat /sys/power/mem_sleep to
           display). See the kernel documentation page Basic sysfs
           Interfaces for System Suspend and Hibernation[2] for more
           details.

           Added in version 256.

       HibernateDelaySec=
           The amount of time the system spends in suspend mode before
           the system is automatically put into hibernate mode. Only
           used by systemd-suspend-then-hibernate.service(8). Refer to
           suspend-then-hibernate for details on how this option
           interacts with other options/system battery state.

           Added in version 239.

       SuspendEstimationSec=
           The RTC alarm will wake the system after the specified
           timespan to measure the system battery capacity level and
           estimate battery discharging rate. Only used by
           systemd-suspend-then-hibernate.service(8). Refer to
           suspend-then-hibernate for details on how this option
           interacts with other options/system battery state.

           Added in version 253.

EXAMPLE: FREEZE         top

       Example: to exploit the β€œfreeze” 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)

NOTES         top

        1. πŸ’£πŸ’₯🧨πŸ’₯πŸ’₯πŸ’£ Please note that those configuration files must
           be available at all times. If /usr/local/ is a separate
           partition, it may not be available during early boot, and
           must not be used for configuration.

        2. Basic sysfs Interfaces for System Suspend and Hibernation
           https://docs.kernel.org/admin-guide/pm/sleep-states.html#basic-sysfs-interfaces-for-system-suspend-and-hibernation

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 2024-06-14.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2024-06-13.)  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 257~devel                                  SYSTEMD-SLEEP.CONF(5)

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