systemd-hibernate-resume.service - Man Page

systemd-hibernate-resume​.service

systemd-hibernate-clear​.service

/usr/lib/systemd/systemd-hibernate-resume

systemd-hibernate-resume​.service initiates the resume from hibernation​.

systemd-hibernate-resume only supports the in-kernel hibernation implementation, see Swap suspend​^[1]​. Internally, it works by writing the major:minor of selected device node to /sys/power/resume, along with the offset in memory pages (/sys/power/resume_offset) if supported​.

The resume device node is either passed directly through arguments, or automatically acquired from kernel command line options and/or HibernateLocation EFI variable​. The latter will normally be cleared by systemd-hibernate-resume​.service on resumption​. If a stale variable is detected, it would be cleared by systemd-hibernate-clear​.service​.

Failing to initiate a resume is not an error condition​. It may mean that there was no resume image (e​. g​. if the system has been simply powered off and not hibernated)​. In such cases, the boot is ordinarily continued​.

systemd(1), systemd-hibernate-resume-generator(8)

1.

Swap suspend
https://docs.kernel.org/power/swsusp.html