When the user presses Ctrl-Alt-Del more than 7x within 2s an immediate reboot is triggered. This useful if shutdown hung and is unable to complete, to expedite the operation. Note that this kind of reboot will still unmount all file systems, and hence should not result in fsck being run on next reboot.

Если в вашем опенспейсе кто-то усердно ебашит по клавиатуре, знайте - у него не эпилептический припадок, а попросту завис компьютер с systemd.