systemd Developer Zbigniew Jędrzejewski-Szmek zbyszek@in.waw.pl systemd-sleep.conf 5 systemd-sleep.conf sleep.conf.d Suspend and hibernation configuration file /etc/systemd/sleep.conf /etc/systemd/sleep.conf.d/*.conf /run/systemd/sleep.conf.d/*.conf /usr/lib/systemd/sleep.conf.d/*.conf 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 the system is initially suspended (the state is stored in RAM). If not interrupted within the delay specified by HibernateDelaySec=, the system will be woken using an RTC alarm and hibernated (the state is then stored on disk). Settings in these files determine what strings will be written to /sys/power/disk and /sys/power/state by systemd-sleep8 when systemd1 attempts to suspend or hibernate the machine. The following options can be configured in the [Sleep] section of /etc/systemd/sleep.conf or a sleep.conf.d file: SuspendMode= HibernateMode= HybridSleepMode= The string to be written to /sys/power/disk by, respectively, systemd-suspend.service8, systemd-hibernate.service8, systemd-hybrid-sleep.service8, or systemd-suspend-then-hibernate.service8. 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. SuspendState= HibernateState= HybridSleepState= The string to be written to /sys/power/state by, respectively, systemd-suspend.service8, systemd-hibernate.service8, systemd-hybrid-sleep.service8, or systemd-suspend-then-hibernate.service8. 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. HibernateDelaySec= The amount of time in seconds that will pass before the system is automatically put into hibernate when using systemd-suspend-then-hibernate.service8. Example: to exploit the freeze mode added in Linux 3.9, one can use systemctl suspend with [Sleep] SuspendState=freeze systemd-sleep8, systemd-suspend.service8, systemd-hibernate.service8, systemd-hybrid-sleep.service8, systemd-suspend-then-hibernate.service8, systemd1, systemd.directives7