Template:Article summary text Template:Article summary heading Template:I18n entry Template:Article summary heading Template:Article summary wiki Template:Article summary wiki Template:Article summary wiki Template:Article summary end This article describes how to suspend a computer to disk. This means that all the running processes are saved to the hard drive and the power is completely shut down. The article discusses the two main methods to accomplish this task, that is userspace suspension (uswsusp) and tuxonice (formerly known as suspend2). See the ususpend website and the tuxonice website for complete documentation. There is a third method: using the kernelspace functionalities of the vanilla kernel. However, this method is the least developed, the slowest and the less reliable. On the contrary, tuxonice and ususpend are competing in features and stability. The only method to decide which method is better for you is to try both of them. From a general point of view, we can say that uswsusp does not force you to patch, configure and compile a kernel, while tuxonice does. However, tuxonice can be used without an initrd/initramfs, while using ususpend without an initrd/initramfs is discouraged; moreover, tuxonice allows you to suspend on a regular file if you have not a swap partition, while uswsusp give this possibility only if you run an experimental and unstable mm kernel.
It is important to distinguish the core method of suspension to disk from the userspace application which you use to hibernate your machine to disk. A userspace application is required because the large majority of the laptops require some quirks in order to accomplish a proficient, successful hibernation cycle: unloading modules, restarting services, unmount windows partitions and usb keys, and so on.
There are two widely used userspace applications for this purpose: pm-utils and hibernate-script. You can find pm-utils in [extra] and hibernate-script in AUR. However, since in this guide we need to describe two different, competing core methods, we will focus on the hibernate-script. The script, developed by the tuxonice development team, can be used nonetheless also to hibernate your machine with the ususpend method, and even to suspend the machine to ram (actually it is an excellent tool also for this task, but we are not going to discuss this aspect in this document, see Suspend to RAM).
If you prefer to use pm-utils, refer to the specific wiki article. pm-utils is a serious competitor of the hibernate-script. Nonetheless, the hibernate-script is still much more configurable and documented, so this guide still assumes that you are using it (although it is very easy to translate each info for pm-utils).
The discussion will be articulated in four parts. First of all, we will discuss the userspace method, secondly the tuxonice one, thirdly we will see how to use the power of the hibernate-script in order to circumvent some problems which could impair your ability to accomplish successful suspend/resume cycles. These last tips can be used with both methods. On the contrary, the first two parts will include instructions to use the hibernate-script in order to accomplish the basic operations with the two methods. In the fourth and last part, we will see how to combine suspension to disk and Suspend to RAM.
- 1 Installation
- 2 Uswsusp method
- 3 Tuxonice method
- 4 Hibernate tricks with the hibernate.script
- 5 Combining suspend to disk with suspend to RAM
- 6 Take action based on events
The userspace method lets you resort to some advanced suspension abilities included in vanilla kernels > 2.6.17. You need two userspace tools, called s2disk and resume, which do what their names say. They are both included in the AUR package uswsusp-git (which includes also s2ram, see Suspend to RAM ).
On the contrary, you need to edit the s2disk configuration file, called /etc/suspend.conf. It is essential that you modify the resume device parameter:
resume device = /dev/sda3
It needs to point to your swap partition: in this case, the third partition of a primary pata-sata drive. It is also a good thing to enable compression, because this speeds up greatly your suspension/resume routine.
Note that it is important that this configuration file be edited *before* recreating the initramfs (done below). Presently, the initramfs build process reads this configuration file, and embeds the current resume parameter. If not changed from the default '<path_to_resume_device_file>', this causes problems such as seeing, on bootup:
# Could not stat the resume device file '<path_to_resume_device_file>' # Please type in the full path name to try again or press ENTER to boot the system.
If you have experiencing this problem, simply edit the file as appropriate, and then rebuild the initramfs.
Another line that you may want to add to the configuration file is:
shutdown method = shutdown
This explicitly configures the system to shutdown instead of reboot.
Recreate the intramfs
Now you need to recreate an initramfs with the new hook. So edit the /etc/mkinitcpio.conf file. In the HOOKS list add the uresume hook (it is different from the resume hook, which is on the contrary required by the tuxonice method). You should put it immediately before the filesystem hook. When the hook is executed the device file for the swap partition (which you have defined in /etc/suspend.conf) needs to exist (the standard udev hook will take care of this). Now proceed to regenerate your initramfs:
# mkinitcpio -p kernel26
You need to adjust this command according to the kernel you plan to use and the name of the initramfs in the grub configuration. Anyway you should not need to modify anything in the grub configuration.
Suspend to file support
uswsusp also supports suspending to a swapfile (and perhaps a dedicated hibernation file). The procedure is identical to using a swap partition with these exceptions:
In addition to specifying the resume device on the kernel command line, a resume_offset parameter must also be set. This same parameter must be included in /etc/suspend.conf as resume offset
The offset parameter can be obtained by running the command
# swap-offset FILENAME.
Support for splash screens
The uswsusp-git package does not provide support for splash screens: for Fbsplash there is the uswsusp-fbsplash package and for Splashy the uswsusp-splashy-git package in the AUR. For splash see the HOWTO and README in the source tarball for details if you want to modify the PKGBUILD yourself.
Setting the suspend method
If you use hibernate-script, your preferred suspend/hibernation method 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 swsusp).
For Uswsusp use:
Or just try to do it like:
# echo "SLEEP_MODULE=uswsusp">>/etc/pm/config.d/module
Now you could try to suspend directly calling s2disk from the command line:
However, this is highly likely to fail, because some services could need to be stopped, some modules unloaded, etc. Thus it is probably necessary to resort to a userspace tool which calls internally s2disk, like Pm-utils since version 1.1 (which is now in core) or hibernate-script. See below about details for defining the ususpend-disk method as default in /etc/hibernate/hibernate.conf. For the moment being, remember that you can define specific options in /etc/hibernate/ususpend-disk.conf and, after having configured also /etc/hibernate/common.conf, you can suspend to disk with the uswsusp method with the following command:
# hibernate -F /etc/hibernate/ususpend-disk.conf
Support for encryption
- generate a key with the suspend-keygen utility included in the package;
- write the name of the key in /etc/suspend.conf;
- uncomment or add the following line in /etc/suspend.conf
encrypt = y RSA key file = <path_to_keyfile>
- build a new initramfs with the uresume hook just before the filesystem one.
There is a dedicated Tuxonice page which covers the basics of installing and configuring Tuxonice.
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.
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 don't explicitly restore the volume levels, ALSA may have the sound channels muted after resuming. If this happens, look for:
/etc/hibernate/common.conf and change the line just below to:
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 firstname.lastname@example.org 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 unload 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/common.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. The downside is the risk of crashing your system. but I have had no trouble with it so far, while reducing the size of the suspended image by half. Just add something like this to the common.conf:
OnSuspend 00 sync; echo 3 > /proc/sys/vm/drop_caches
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
Edit the following file
# 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
# 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
Alternatively you can edit
/etc/acpi/actions/lm_lid.sh this is the file that is executed when the lid state is changed
#!/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
This script is derived from The Gentoo Wiki. 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.
Interacting with HAL
With new versions of HAL and policykit (>= 0.5.11-7, 0.9-7), the following is enough to make sure hal-triggered hibernates (e.g. from gnome-power-manager or xfce-power-manager) use hibernate-script. Make sure policykit is installed, add your username to the "power" group, then edit the following lines in
/usr/lib/hal/scripts/linux/hal-system-power-hibernate-linux in the place where pm-hibernate is called, so it looks like this:
# We only support pm-utils...not anymore! if [ -x "/usr/sbin/hibernate" ] ; then # Suspend2 tools installed /usr/sbin/hibernate --force RET=$? elif [ -x /usr/sbin/pm-hibernate ] ; then /usr/sbin/pm-hibernate $QUIRKS RET=$? else unsupported fi
Now restart HAL
/etc/rc.d/hal restart and give it a shot.
The previous method, which may be outdated, is to create script /usr/lib/hal/scripts/hal-system-power-hibernate-own :
#!/bin/sh ## /usr/lib/hal/scripts/hal-system-power-hibernate-own . hal-functions hal_check_priv org.freedesktop.hal.power-management.hibernate ## suspend command # replace this with command you want to use # hibernate s2disk
Give right permissions with command
chmod 655 /usr/lib/hal/scripts/hal-system-power-hibernate-own
Next you have to replace old command with new. Create file /etc/hal/fdi/policy/09-power-mgmt-policy.fdi
<?xml version="1.0" encoding="UTF-8"?> <deviceinfo version="0.2"> <device> <match key="info.udi" string="/org/freedesktop/Hal/devices/computer"> <merge key="org.freedesktop.Hal.Device.SystemPowerManagement.method_execpaths" type="strlist">hal-system-power-suspend</merge> <append key="org.freedesktop.Hal.Device.SystemPowerManagement.method_execpaths" type="strlist">hal-system-power-suspend-hybrid</append> <append key="org.freedesktop.Hal.Device.SystemPowerManagement.method_execpaths" type="strlist">hal-system-power-hibernate-own</append> <append key="org.freedesktop.Hal.Device.SystemPowerManagement.method_execpaths" type="strlist">hal-system-power-shutdown</append> <append key="org.freedesktop.Hal.Device.SystemPowerManagement.method_execpaths" type="strlist">hal-system-power-reboot</append> <append key="org.freedesktop.Hal.Device.SystemPowerManagement.method_execpaths" type="strlist">hal-system-power-set-power-save</append> </match> </device> </deviceinfo>
Finally restart HAL