systemd-hibernate-resume@.service, systemd-hibernate-resume - Resume from hibernation

       systemd-hibernate-resume@.service initiates the resume from hibernation. It is instantiated with the
       device to resume from as the template argument.

       systemd-hibernate-resume only supports the in-kernel hibernation implementation, known as swsusp[1].
       Internally, it works by writing the major:minor of specified device node to /sys/power/resume.

       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 case, the boot is ordinarily
       continued.

       systemd-hibernate-resume@.service, systemd-hibernate-resume - Resume from hibernation

        1. swsusp
           https://www.kernel.org/doc/Documentation/power/swsusp.txt

systemd 249                                                                 SYSTEMD-HIBERNATE-RESUME@.SERVICE(8)

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

       systemd-hibernate-resume@.service

       /lib/systemd/systemd-hibernate-resume