# Suspending to Disk with hibernate-script

Related articles

- Suspending to RAM with hibernate-script
- pm-utils
- Laptop

"Hibernating" or suspending to disk writes all the running processes to the disk (typically to the swap partition), then completely powers down the machine. This resembles suspending to RAM, but while a machine suspended to RAM still requires a small charge from a battery or power source, a hibernated machine does not and can remain hibernated indefinitely. This advantage comes at the cost of additional time needed to hibernate and to resume, since disks (especially HDD swap partitions) write and read slower than RAM.

This guide focuses on hibernate-script (see the pm-utils page for the alternative), a frontend used with the uswsusp ("userspace suspension") and TuxOnIce (formerly known as suspend2) hibernate backends. Uswsusp generally works without requiring a patched kernel but should be used with initrd/initramfs. Tuxonice requires a modified kernel, but works without initrd/initramfs and also allows suspending to a swap file if a user does not have, or does not want to use, a swap partition.

## Installation

You can install hibernate-script from the AUR.

## Backend setup

There is a dedicated pages which covers the installing and configuring of these backend:

- Tuxonice method: Tuxonice
- Uswsusp method: Uswsusp

### Direct Run

you can suspend to disk with the method with the following command.

Using uswsusp:

    # hibernate -F /etc/hibernate/ususpend-disk.conf

Using TuxOnIce:

    # hibernate -F /etc/hibernate/tuxonice.conf

### Setting the suspend method

Preferred suspend/hibernation method of hibernate-script can be set in the file `/etc/hibernate/hibernate.conf`. If you list several methods, the first one will be used. Note that hibernate can also be used with Suspend to RAM or vanilla uswsusp).

For Uswsusp use:

    TryMethod ususpend-disk.conf

For TuxOnIce use:

    TryMethod tuxonice.conf

## Hibernate tricks with the hibernate.script

This is a brief overview of the hibernate script. If you want to tweak it further, examine the `common.conf` and `suspend2.conf` files further and read the excellent and exhaustive man pages for hibernate and `hibernate.conf`.

### Editing /etc/hibernate/common.conf

The options in this file are used with any hibernation method (actually, the file is sourced by the configuration files of each method) and also by Suspend to RAM when accomplished with the hibernate-script. This file is complex and well commented. The man page `hibernate.conf` describes adequately all the options. Here, we can only stress the most commonly useful parts.

Uncomment the lines for any filesystems that have the potential to change while your computer is suspended (for example shared partitions with windows like vfat or ntfs ones). They will be remounted upon resume. Otherwise you would risk corrupting the filesystems.

    ### filesystems
    # Unmount /nfsshare /windows /mnt/sambaserver
    # UnmountFSTypes smbfs nfs
    # UnmountGraceTime 1
    # Mount /windows

If you do not explicitly restore the volume levels, ALSA may have the sound channels muted after resuming. If this happens, look for:

    ### services

in `/etc/hibernate/common.conf` and change the line just below to:

    RestartServices alsa

The alsa service will be stopped before suspension and restarted after resuming: the sound channels and volumes will be as before. You may want to restart other problematic services here.

A common issue is that some drivers do not support suspension, that is they do not work properly after a suspension cycle or even they prevent the system from suspending or resuming properly. In these cases (which should be reported - at least for modules in the vanilla kernel - to the suspend-devel@lists.sourceforge.net mailing list, so that they can be fixed upstream) you can unload the module before suspension and reload it after resuming: the hibernate-script can automatize this routine with the LoadModules and UnloadModules options. Actually, the hibernate-script already unloads some problematic modules, listed in `/etc/hibernate/blacklisted-modules`, so you can also add the modules in that file.

To re-connect to networks after rebooting, you may want to add:

    OnSuspend 25 netcfg2 -a
    OnResume 20 netcfg-auto-wireless <your-network-interface>

This will disconnect from all networks, then should automatically choose the correct one. If you use another way to connect to a network (such as netcfg2 <profile-name> then of-course, put that there instead.

One 'gotcha' to watch out for is the priority level you put on your user-commands, this won't work:

    OnSuspend 5 netcfg -a

You'll need to set the priority as 05 instead. Its normally best to use something within the range of 20-50 for your user scripts.

If you need/want to eject all PcCards before suspending and reinsert them after resuming, change the EjectCards setting in `common.conf`:

    ### pcmcia
    EjectCards yes

This is necessary on some laptops, if the pccards stop working after resume.

Finally, the most problematic aspect is constituted by the video card: its status needs often to be restored after resuming. In other cases, it is necessary to switch from X to the console. The following options in `/etc/hibernate/common.conf` will probably fix these issues (whose symptom could be a frozen machine or only a black display after resuming):

    ### vbetool
    #EnableVbetool yes
    #RestoreVbeStateFrom /var/lib/vbetool/vbestate
    #VbetoolPost yes
    # RestoreVCSAData yes

    ### xhacks
    #SwitchToTextMode yes
    #UseDummyXServer yes
    #DummyXServerConfig xorg-dummy.conf

You can uncomment one or many of them in order to see if the problem is solved. In order to use the first block of options, you need to install the vbetool package from the extra repository. Each of the option is documented in man `hibernate.conf`. Please note that it is very important to try all the different combinations of these options before than anything else, becaause the problems with the display are the most common source of troubles in a suspension cycle.

### NVIDIA specific settings

If you have an NVIDIA graphics card and use a driver version >177, you need to add the following line to `/etc/hibernate/tuxonice.conf`:

    ProcSetting extra_pages_allowance 7500

A value lower than 7500 might also work on certain systems, though 7500 should be a working default. Setting this option should allow you to hibernate and resume without any additional X hacks. You will also need to comment out the nvidia module in `/etc/hibernate/blacklisted-modules` for this to work.

The suggested value for extra_pages_allowance for driver versions <177 is 0:

    ProcSetting extra_pages_allowance 0

This setting has also been reported to help with the binary ATI driver.

If you have an AGP Nvidia card and are using the binary driver, you might also have to add the following line to your `/etc/X11/xorg.conf`:

    Option "NvAGP" "1"

### Suspending with fglrx

Following addition to `/etc/hibernate/suspend2.conf` is required:

    # For fglrx
    ProcSetting extra_pages_allowance 20000

### Dropping disk caches

  From: drop_caches introduction

As a way to speed up suspending, you can free the memory used for disk caches so there will be less to write to the disk. Just add something like this to the `common.conf`:

    OnSuspend 00 sync; echo 3 > /proc/sys/vm/drop_caches

### Specific settings for TuxOnIce

Specific settings for TuxOnIce are in `/etc/hibernate/tuxonice.conf`. Make sure that the following lines are uncommented and appropriately configured:

    UseTuxOnIce   yes
    Compressor    lzo

There are a number of additional settings and tweaks which you can set in `/etc/hibernate/tuxonice.conf` and `/etc/hibernate/common.conf`, more information about these can be found on the TuxOnIce website and on the Suspend to Disk page of this wiki.

You can abort a suspend cycle if you press the escape key. If you press a capital R, you will force the system to reboot after hibernation.

If all goes well, you should be able to resume using the same GRUB menu selection. If you make that option the default for GRUB, you will always default to resuming if a resume image is available. It is recommended that you test the suspend/hibernate from a text console first and then once you have confirmed that it works try it from within X.

Warning: Never use a different kernel to resume than you used to suspend! If pacman updates your kernel, do not suspend before you have rebooted properly.

You can make this practice safer adding the hibernate-cleanup daemon to your DAEMONS array in `/etc/rc.conf`. This script will make sure that any stale image is deleted from your swap partition at boot time. This should make your system safe also in the case that you have chosen the mistaken kernel at the GRUB prompt. The hibernate-cleanup service is included in the hibernate-script package.

## Combining suspend to disk with suspend to RAM

If your motherboard or laptop supports Suspend to RAM, you can combine it with suspend2. This will result in the following behavior:

- When you call hibernate, your system will suspend to disk and after that suspend to RAM instead of powering down.
- When you turn your system back on, it will resume directly from RAM (which only takes a few seconds)
- If your battery fails in the meantime (and the image in your memory is therefore lost), you will be able to resumes from disk.

This can be done both with uswsusp and with tuxonice.

With uswsusp, you should use s2both. You can also call s2both from the hibernate script (with all its richness of options), resorting to the `ususpend-both.conf` method. Please note that s2both works only if s2ram (see Suspend to RAM) works in your system. There is no way to force it to work if your laptop model is not whitelisted in s2ram. See Suspend to RAM for instructions about how to whitelist your laptop in the local copy of s2ram and how to report that your laptop suspend to ram properly so that it is whitelisted in the next uswsusp release.

To do it with tuxonice, edit `/etc/hibernate/suspend2.conf`:

    ## Powerdown method - 3 for suspend-to-RAM, 4 for ACPI S4 sleep, 5 for poweroff
    PowerdownMethod 3

For this to work, your computer must be able to use suspend to RAM also without s2ram.

## Take action based on events

Tuning hibernate-script for context sensitive modal operation. You need to have acpid installed.

### After pressing power button

Edit the following file `/etc/acpi/events/power`

    # This is called when the user presses the power button
    event=button/power (PWR.||PBTN)
    # To Hibernate uncomment the following line
    #action=hibernate
    # To Suspend uncomment the following line
    #action=suspend

### After closing lid

Edit the following file `/etc/acpi/events/lid`

    # This is called when the user closes the lid
    event=button/lid
    # To Hibernate uncomment the following line
    #action=hibernate
    # To Suspend uncomment the following line
    #action=suspend

You can also install lidsleep which includes the file altered to use pm-utils and suspend to RAM.

Alternatively you can edit `/etc/acpi/actions/lm_lid.sh` this is the file that is executed when the lid state is changed

Example:

    #!/bin/bash
    # lid button pressed/released event handler
    #laptop mode helps minimized hdd activity
    test -x /usr/sbin/laptop_mode && /usr/sbin/laptop_mode auto
    # get the -xauth variable so we can access the display
    XAUTH="$( ps -C X f | sed -n 's/.*-auth \(.*\)/\1/p' )"
    if [[ -z $XAUTH ]]; then
      # if XAUTH is blank try another way to get it
      XAUTH="$( ps -C xinit f | sed -n 's/.*-auth \(.*\)serverauth.*/\1Xauthority/p' )"
    fi
    #Find out if the lid is open or closed
    if grep -q open /proc/acpi/button/lid/LID/state; then
      # the screen is on, forces it to be on
      ACTION="on"
      XAUTHORITY=$XAUTH /usr/bin/xset -display :0.0 dpms force $ACTION
    else
      # screen is off, forces off
      ACTION="off"
      XAUTHORITY=$XAUTH /usr/bin/xset -display :0.0 dpms force $ACTION
      # script waits for 10 minutes
      sleep 10m
      # checks to make sure screen is still closed
      if grep -q closed /proc/acpi/button/lid/LID/state; then
        # if it is, then it suspends to disk
        s2disk
      else
        # or it turns it back on
        XAUTHORITY=$XAUTH /usr/bin/xset -display :0.0 dpms force on
      fi
    fi

The script turns the monitor off or on. But if the screen is left shut for 10 minutes, it will suspend to the disk automatically. `man sleep` for more info on the sleep command.

Category:

- Power management