Debugging Central This page is part of the debugging series — pages with debugging details for a variety of Ubuntu packages. For issues regarding suspend to disk i. Linux provides an ACPI subsystem that manages the suspend and resume process. Usually problems occur when resuming, and normally the culprit is a device driver that does not recover from a powered down state. If your computer successfully performs a suspend, then it is quite likely any resume problems are due to another device driver and not the ACPI subsystem. The approach used here needs to make notes on progress during resume and be able to recover them after a manual reboot.
To use suspend, an operating system must first configure wake-up events things like the power button, lid-button, etc. Assuming the "mem" suspend, the kernel does the following: logically ejects all CPUs except boot processor disables devices call suspend functions saving configuration registers enter D3 state consuming 0 or nearly 0 power read ACPI FADT fixed address descriptor table magic values write ACPI registers with magic values BIOS enters "system management mode", directly interacting with the hardware PTS: prepare to sleep GTS: go to sleep may cause BIOS to cut power to various power planes wake-up event occurs BIOS checks for resume vs new boot BIOS runs kernel's wake-up code and re-enters the kernel enable devices enter D0 state working restore configuration registers logically re-inject all CPUs Above the kernel layer, user-space must do work before handing off control to the above kernel procedures. HAL makes calls to this script when reacting to various key presses or power management events. The goal is to move to pmutils in Hardy. CategoryDocumentation UnderstandingSuspend last edited by psusi. Partners Support Community Ubuntu. UnderstandingSuspend last edited by psusi.
Edit the SystemD hibernate service using sudo systemctl edit systemd-hibernate. It's tested against a stock Ubuntu This worked for me, thanks for the writeup! What's missing though is: can the system put itself into hibernation when the battery is low? Can I get a "hibernate"-button in the menu that also has "shut down"?
It only takes a minute to sign up. Connect and share knowledge within a single location that is structured and easy to search. Look at that third column. The shell you want is the one with the T , and that one has a PID first column of