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[[ru:Laptop]]
 
[[ru:Laptop]]
 
[[zh-CN:Laptop]]
 
[[zh-CN:Laptop]]
== Setting Up For Laptops ==
+
This page should contain links to pages needed for configuring a laptop for the best experience. Setting up a laptop is in many ways the same as setting up a desktop. However, there are a few key differences. Arch Linux provides all the tools and programs necessary to take complete control of your laptop. These programs and utilities are highlighted below, with appropriate tips tutorials.
This page should contain links to pages needed for configuring a laptop for the best experience. Setting up a laptop is in many ways the same as setting up a desktop. However, there are a few key differences. When setting up a laptop with Arch Linux, the following points should be taken into consideration:
+
  
* [[#Power Management]] Power Management for laptops refers to optimizing the system to last as long as possible on a single battery charge. This can be accomplished by a variety of tweaks.
+
== Power management ==
** [[#Suspend and Hibernate]] : the operating system can be manually suspended either to memory or to disk, allowing for an (almost) complete shutdown of other hardware.
+
** Hard drive spindown : the system can be configured to automatically turn off the hard disk after a specified interval of inactivity.
+
** Screen shut off : the laptop screen can be configured to automatically turn off after a specified interval of inactivity (not just blanked with a screensaver but completely shut off).
+
** CPU frequency scaling : the processor(s) can be configured to automatically step down to a lower frequency at lower loads.
+
  
* [[#Screen brightness]]. How do I manage screen brightness?
+
{{Note|You should read the main articles [[Power Management]] and [[Power saving]]. Additional laptop-specific features are described below.}}
* Network and wireless setup is described in [[Wireless Setup]].
+
* Media buttons can be configured as described in [[Extra Keyboard Keys]].
+
* [[#Touchpad]] sensitivity, acceleration, button function and scroll borders can be configured for some (Synaptics or Alps) touchpads.
+
* [[#Hard disk shock protection]]
+
  
All of these points are important to take into consideration when getting a laptop set up the way you like. Fortunately, Arch Linux provides all the tools and programs necessary to take complete control of your laptop. These programs and utilities are highlighted below, with appropriate tips tutorials.
 
 
== Power Management ==
 
 
Power management is very important for anyone who wishes to make good use of their battery capacity. The following tools and programs help to increase battery life and keep your laptop cool and quiet.
 
Power management is very important for anyone who wishes to make good use of their battery capacity. The following tools and programs help to increase battery life and keep your laptop cool and quiet.
  
=== Battery State ===
+
=== Battery state ===
 +
 
 +
Reading battery state can be done in multiple ways. Classical method is some daemon periodically polling battery level using ACPI interface. On some systems, battery sends events to [[udev]] whenever it (dis)charges by 1%, this event can be connected to some action using udev rule.
 +
 
 +
==== ACPI ====
 +
 
 +
Battery state can be read using ACPI utilities from the terminal. ACPI command line utilities are provided via the {{Pkg|acpi}} package. See [[ACPI modules]] for more information.
 +
 
 +
* {{AUR|batterymon-clone}} is a simple battery monitor that sits in the system tray.
 +
* {{Pkg|batti}} is a simple battery monitor for the system tray, similar to batterymon-clone. Unlike the former {{ic|batti}} uses UPower, and if that is missing {{ic|DeviceKit.Power}}, for it's power information.
  
 
==== Udev events ====
 
==== Udev events ====
Upon change battery sends events which can be handled by udev. Example of how it could be used is presented below.
 
  
==== Low charge action ====
+
If your battery sends events to [[udev]] whenever it (dis)charges by 1%, you can use this udev rule to automatically suspend the system when battery level is critical, and thus prevent all unsaved work from being lost.
  
By default, system won't do anything if your laptop's battery is going to discharge. In order not to lose all unsaved work this example udev rule could be used:
 
 
{{hc|/etc/udev/rules.d/lowbat.rules|<nowiki>
 
{{hc|/etc/udev/rules.d/lowbat.rules|<nowiki>
## SLEEP IF BATTERY IS LOW
+
# Suspend the system when battery level drops to 2%
 
SUBSYSTEM=="power_supply", ATTR{status}=="Discharging", ATTR{capacity}=="2", RUN+="/usr/bin/systemctl suspend"
 
SUBSYSTEM=="power_supply", ATTR{status}=="Discharging", ATTR{capacity}=="2", RUN+="/usr/bin/systemctl suspend"
 
</nowiki>}}
 
</nowiki>}}
 +
 
Likewise, the rule can be customized to perform other action on different status.
 
Likewise, the rule can be customized to perform other action on different status.
  
==== Utilities ====
+
=====Testing events=====
  
Battery state can be read using ACPI utilities from the terminal. ACPI command line utilities are provided via the {{Pkg|acpi}} package. A simple battery monitor that sits in the system tray is {{AUR|batterymon-clone}} which can be found in the [[Arch User Repository|AUR]].
+
One way to test udev rules is to have them create a file when they are run. For example:
  
{{Tip|More information can be found in the [[ACPI modules]] article.}}
+
{{hc|/etc/udev/rules.d/98-discharging.rules|<nowiki>
 +
SUBSYSTEM=="power_supply", ATTR{status}=="Discharging", RUN+="/usr/bin/touch /home/example/discharging"
 +
</nowiki>}}
  
* {{pkg|batti}} is a simple battery monitor for the system tray, similar to batterymon-clone. Unlike the latter {{ic|batti}} uses UPower, and if that is missing DeviceKit.Power, for it's power information.
+
This creates a file at {{ic|/home/example/discharging}} when the laptop charger is unplugged. You can test whether the rule worked by unplugging your laptop and looking for this file. For more advanced udev rule testing, see [[Udev#Testing rules before loading]].
  
 
=== Suspend and Hibernate ===
 
=== Suspend and Hibernate ===
  
Manually suspending the operating system, either to memory (standby) or to disk (hibernate) sometimes provides the most efficient way to optimize battery life, depending on the usage pattern of the laptop. While there is relatively straightforward support in the linux kernel to support these operations, typically some adjustments have to be made before initiating these operations (typically due to problematic drivers, modules or hardware). The following tools provide wrappers around the kernel interfaces to suspend/resume :
+
Manually suspending the operating system, either to memory (standby) or to disk (hibernate) sometimes provides the most efficient way to optimize battery life, depending on the usage pattern of the laptop.
  
* [[Acpid]]
+
See the main article [[Suspend and Hibernate]].
* [[Pm-utils]]
+
* [[Uswsusp]]
+
  
which are described in more detail in [[Suspend]].
+
==== Hard drive spin down problem ====
  
===Power saving===
 
 
See the main article, [[power saving]].
 
 
==== Automatic tweaks for battery life ====
 
 
As opposed to manually initiated actions like suspend/hibernate, a number of tweaks can be made to prolong the battery life of the laptop under low/idle usage.
 
 
* [[CPU Frequency Scaling]] is a technology used primarily by notebooks which enables the OS to scale the CPU frequency up or down, depending on the current system load and/or power scheme.
 
* [[Laptop Mode Tools]] provides a comprehensive suite of tools to tweak a large number of power saving settings through well documented configuration files.
 
* [[Powertop]] is a handy utility from Intel that displays which hardware/processes are using the most power on your system, and provides instructions on how to stop or remove power-wasting services. Works great for mobile Intel CPUs; provides the current CPU state and suggestions for power saving. Also works on AMD systems, but does not provide as much information about the CPU state.
 
 
The following options are specific to certain laptop types:
 
 
* [[Asus_G1#The_Lapsus_daemon_.26_KDE_applet|Lapsus]] is a set of programs providing easy access to many features of various laptops. It currently supports most features provided by asus-laptop kernel module from ACPI4Asus project, such as additional LEDs, hotkeys, backlight control etc. It also has support for some IBM laptops features provided by IBM ThinkPad ACPI Extras Driver and NVRAM device.
 
* Battery tweaks for Thinkpads can be found in the [[tp_smapi]] article.
 
* [[TLP]] for Thinkpads is a set of scripts, which set many powersaving options according to the current Powersource. [[TLP]] is intended to be used on Thinkpads, but most settings should work on other laptops too.
 
 
====PCI-e ASPM====
 
On some laptops, powertop suggests enabling the {{ic|CONFIG_PCIEASPM}} kernel option. It can be found under "Bus options (PCI etc.)"->"PCI Express ASPM support". This option is marked as experimental in the current kernel (2.6.35) and allows the PCI-e links to enter a power saving state.
 
 
According to [http://www.lesswatts.org/projects/devices-power-management/pcie.php], this option might degrade performance a bit, but on an Acer 3820TG laptop, it can reduce power consumption by about one third or even more.
 
 
More experience with this setting would be appreciated, so please share them [https://bbs.archlinux.org/viewtopic.php?id=107173 here]!
 
 
It seems like the option is going to be enabled by default in kernel 2.6.36; if so, the information here will be obsolete soon. However, if your system should be able to make use of this power management feature but you are receiving messages like like the following (check {{ic|/var/log/everything.log*}}):
 
 
disabling ASPM on pre-1.1 PCI-e device.  You can enable it with 'pcie_aspm=force'
 
 
then add {{ic|pcie_aspm<nowiki>=</nowiki>force}} to your kernel command line.
 
 
==== Granola ====
 
 
{{Out of date|Arch Linux has moved to systemd, so rc.conf is no longer used.}}
 
 
[https://aur.archlinux.org/packages.php?ID=36841 Granola] is a daemon that monitors the cpu usage and uses the cpufreq-userspace module to lessen power usage without any noticeable difference in performance.
 
To use it, first install from the AUR:[https://aur.archlinux.org/packages.php?ID=36841], the default settings will work for most setups.
 
You will need to load the cpufreq_userspace module, as well as the cpufreq scaling governor for your CPU at startup.
 
Edit {{ic|/etc/rc.conf}}:
 
For most generic cpus:
 
 
  MODULES=( ... cpufreq_userspace acpi-cpufreq ... )
 
 
For Intel Atom or Pentium 4 cpus:
 
 
  MODULES=( ... cpufreq_userspace p4_clockmod ... )
 
 
Then add Granola to the DAEMONS array:
 
 
  DAEMONS=( ... granola ... )
 
 
and reboot.
 
 
To test if it worked, run:
 
 
  cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq
 
  #OR
 
  cpufreq-info #if you have cpufreq-utils installed
 
 
and check that the cpu frequency is below maximum.
 
 
====Wireless====
 
When working on your notebook/laptop without wireless access, here is a little script for your system startup that turns off your WLAN-Hardware to keep it from wasting power searching for an Access Point:
 
{{Note| Edit if <code>wlan0</code> is not your WLAN-device}}
 
 
{{bc|<nowiki>#!/bin/bash
 
 
essid="`iwconfig wlan0 | grep ESSID | awk {'print $4'}`"
 
if [ "$essid" == "ESSID:off/any" ] ; then
 
sudo iwconfig wlan0 txpower off
 
fi</nowiki>
 
}}
 
Start the script according to your DE/WM options by {{ic|sleep xx && /path/to/script}} depending on how long it usually takes to connect to your Access Point, 60 seconds are a good default value. It checks if you're connected, turning off the device if not. {{ic|# iwconfig wlan0 txpower on}} brings it back up, as well as a reboot.
 
 
{{Tip|It may also be prudent to prevent your wireless interface from starting at boot if it is not used often (e.g. netcfg-menu as needed).}}
 
 
==== Disk-related tweaks ====
 
Disable file access time: every time you access (read) a file the filesystem writes an access time to the file metadata. You can disable this on individual files by using the chattr command, or you can enable it on an entire disk by setting the ''noatime'' option in your fstab, as follows:
 
 
/dev/sda1          /          ext3          defaults,noatime          1  2
 
 
[http://www.faqs.org/docs/securing/chap6sec73.html Source]
 
 
{{Note|
 
* Disabling {{ic|atime}} causes troubles with [[Mutt|mutt]] and other applications that make use of file timestamps. Consider compromising between performance and compatibility by using mount option {{ic|relatime}} instead, or look into [http://wiki.mutt.org/?MaildirFormat mutt work-around for noatime].
 
* {{ic|relatime}} is used by default as of kernel 2.6.30, so unless you're using an older kernel, there should be no need to edit fstab.
 
}}
 
 
To allow the CD/DVD rom to spin down after a while using [[udisks]]:
 
 
# udisks --inhibit-polling /dev/sr0
 
 
==== More tweaks ====
 
These are some generic suggestions that will work with most laptops.
 
 
Add the following to {{ic|/etc/modprobe.d/modprobe.conf}}:
 
 
options usbcore autosuspend=1
 
 
Add the following to {{ic|/etc/sysctl.conf}}
 
 
vm.dirty_writeback_centisecs=1500
 
vm.laptop_mode=5
 
 
{{Note|''laptop-mode-tools'' automatically rewrites these values based on the values {{Ic|LM_BATT_MAX_LOST_WORK_SECONDS}}, {{Ic|LM_AC_MAX_LOST_WORK_SECONDS}} (both multiplied by 100) resp. {{Ic|LM_SECONDS_BEFORE_SYNC}}, which are set in {{ic|/etc/laptop-mode/laptop-mode.conf}}. However, that only happens if the three "Enable laptop mode" variables in the same file are set accordingly — left to 0, it resets the values to kernel defaults (500 / 0) for the corresponding scenario regardless of {{ic|/etc/sysctl.conf}}.}}
 
 
{{accuracy|reason=This belongs in a udev rule, not rc.local.}}
 
 
Add the following to {{ic|/etc/rc.local}} (and make sure it gets executed at boot time)
 
 
/usr/sbin/iwpriv your_wireless_interface set_power 5
 
 
Source: [http://www.nervous.it/2007/11/linux-dell-xps-m1330/ here]
 
 
==== Hard drive spin down problem ====
 
 
Documented [https://bugs.launchpad.net/ubuntu/+source/acpi-support/+bug/59695 here]
 
Documented [https://bugs.launchpad.net/ubuntu/+source/acpi-support/+bug/59695 here]
  
To prevent your laptop hard drive from spinning down too often (result of too aggressive APM defaults) do the following:
+
To prevent your laptop hard drive from spinning down too often:
 
+
{{hc|/etc/udev/rules.d/75-hdparm.rules|<nowiki>
Add the following to {{ic|/etc/rc.local}}
+
ACTION=="add", KERNEL=="sd[a-z]", ATTR{queue/rotational}=="1", RUN+="/usr/bin/hdparm -B 254 /dev/$kernel"
 
+
hdparm -B 254 /dev/sdX ''where X is your hard drive device''
+
 
+
If you are using [https://wiki.archlinux.org/index.php/Systemd Systemd]:
+
 
+
Add the following to {{ic|/etc/udev/rules.d/75-hdparm.rules}}
+
ACTION=="add", KERNEL=="sd[a-z]", ATTR{queue/rotational}=="1", RUN+="/sbin/hdparm -B 254 /dev/$kernel"
+
 
+
You can also set it to 255 to completely disable spinning down.  You may wish to set a lower value if you move your laptop around as lower values park the heads more often and reduce the chance of damage to your hard disk while it is being moved.  If you do not move your laptop at all when you are using it, then 255 or 254 is probably best.  If you do, then you might want to try a lower value.  A value like 128 might be a good middle-ground.
+
 
+
Add the following to {{ic|/etc/pm/sleep.d/50-hdparm_pm}}
+
+
#!/bin/sh
+
 
+
if [ -n "$1" ] && ([ "$1" = "resume" ] || [ "$1" = "thaw" ]); then
+
hdparm -B 254 /dev/your-hard-drive > /dev/null
+
fi
+
 
+
and run ''chmod +x /etc/pm/sleep.d/50-hdparm_pm'' to make sure it resets after suspend.  Again, you can change the value 254 as you see fit.
+
 
+
Now the APM level should be set for your hard drive.
+
 
+
For some laptops, the option -S to hdparm can also be relevant (sets the spindown time for the drive). Note that all these options can also be configured using the [[Laptop_Mode_Tools | laptop-mode tools]].  This will allow you to set a high value when on AC and a lower value when you are running on battery power.
+
 
+
=== Using a script and an udev rule ===
+
Since systemd users can suspend and hibernate through {{ic|systemctl suspend}} or {{ic|systemctl hibernate}} and handle acpi events with {{ic|/etc/systemd/logind.conf}}, it might be interesting to remove pm-utils and acpid. Now, there's just one thing systemd can't do (at this time of writing): powermanagement, depending on whether the system is running on AC or battery. To fill this gap, one can create a single udev rule that launches a script when the laptop is unplugged and plugged:
+
{{hc|/etc/udev/rules.d/powersave|2=<nowiki>
+
SUBSYSTEM=="power_supply", ATTR{online}=="0", RUN+="/path/to/your/script true"
+
SUBSYSTEM=="power_supply", ATTR{online}=="1", RUN+="/path/to/your/script false"
+
 
</nowiki>}}
 
</nowiki>}}
{{Note|One can use the same script that pm-powersave uses. You just have to make it executable and place it somewhere else (for example, /usr/bin).}}
 
Examples of powersave scripts can be found here: [https://bbs.archlinux.org/viewtopic.php?pid=1046075#p1046075] (or in aur: {{AUR|powerdown}}), here: [https://github.com/Unia/powersave] and there: [https://aur.archlinux.org/packages/powerconf].
 
  
The above udev rule should work as expected, but if your power settings aren't updated after a suspend or hibernate cycle, you should add a script in {{ic|/usr/lib/systemd/system-sleep/}} with the following contents:
+
See {{ic|hdparm(8)}} for documentation of [[hdparm]] parameters. If you use [[pm-utils]], you might be interested in [[pm-utils#Having the HD power management level automatically set again on resume|these]] examples.
{{hc|/usr/lib/systemd/system-sleep/00powersave|<nowiki>
+
#!/bin/sh
+
  
case $1 in
+
== Screen brightness ==
    pre) /path/to/your/script false ;;
+
    post)     
+
if cat /sys/class/power_supply/AC0/online | grep 0 > /dev/null 2>&1
+
then
+
    /path/to/your/script true
+
else
+
    /path/to/your/script false
+
fi
+
    ;;
+
esac'
+
exit 0
+
</nowiki>}}
+
  
Don't forget to make it executable!
 
{{Note|Be aware that AC0 may be different for your laptop, change it if that is the case.}}
 
 
Now you don't need pm-utils anymore. Depending on your configuration, it may be a dependency of some other package. If you wish to remove it anyway, run {{ic|pacman -Rdd pm-utils}}.
 
 
== Screen brightness ==
 
 
See [[Backlight]].
 
See [[Backlight]].
  
 
== Touchpad ==
 
== Touchpad ==
 +
 
To get your touchpad working properly, see the [[Touchpad Synaptics]] page. Note that your laptop may have an ALPS touchpad (such as the DELL Inspiron 6000), and not a Synaptics touchpad. In either case, see the link above.
 
To get your touchpad working properly, see the [[Touchpad Synaptics]] page. Note that your laptop may have an ALPS touchpad (such as the DELL Inspiron 6000), and not a Synaptics touchpad. In either case, see the link above.
  
 
== Hard disk shock protection ==
 
== Hard disk shock protection ==
 +
 
There are several laptops from different vendors featuring shock protection capabilities. As manufacturers have refused to support open source development of the required software components so far, Linux support for shock protection varies considerably between different hardware implementations.
 
There are several laptops from different vendors featuring shock protection capabilities. As manufacturers have refused to support open source development of the required software components so far, Linux support for shock protection varies considerably between different hardware implementations.
  
Currently, two projects, named HDAPS and hpfall, support this kind of protection.
+
Currently, two projects, named [[Hard Drive Active Protection System|HDAPS]] and {{AUR|hpfall}} (available in the [[AUR]]), support this kind of protection. HDAPS is for IBM/Lenovo Thinkpads and hpfall for HP/Compaq laptops.
HDAPS is for IBM/Lenovo Thinkpads and hpfall for HP/Compaq laptops
+
  
Just Check [[HDAPS|Hard Disk Active Protection System]].
+
== Network time syncing ==
{{AUR|hpfall}} can be installed from the [[AUR]].
+
  
== Network Time Syncing ==
 
 
For a laptop, it may be a good idea to use [[Chrony]] as an alternative to [[NTPd]] to sync your clock over the network. Chrony is designed to work well even on systems with no permanent network connection (such as laptops), and is capable of much faster time synchronisation than standard ntp. Chrony has several advantages when used in systems running on virtual machines, such as a larger range for frequency correction to help correct quickly drifting clocks, and better response to rapid changes in the clock frequency. It also has a smaller memory footprint and no unnecessary process wakeups, improving power efficiency.
 
For a laptop, it may be a good idea to use [[Chrony]] as an alternative to [[NTPd]] to sync your clock over the network. Chrony is designed to work well even on systems with no permanent network connection (such as laptops), and is capable of much faster time synchronisation than standard ntp. Chrony has several advantages when used in systems running on virtual machines, such as a larger range for frequency correction to help correct quickly drifting clocks, and better response to rapid changes in the clock frequency. It also has a smaller memory footprint and no unnecessary process wakeups, improving power efficiency.
  
 
== See also ==
 
== See also ==
 +
 +
; General
 +
* [[CPU Frequency Scaling]] is a technology used primarily by notebooks which enables the OS to scale the CPU frequency up or down, depending on the current system load and/or power scheme.
 +
* [[Display Power Management Signaling]] describes how to automatically turn off the laptop screen after a specified interval of inactivity (not just blanked with a screensaver but completely shut off).
 +
* [[Wireless Setup]] provides information about setting up wireless connection.
 +
* [[Extra Keyboard Keys]] describes configuration of Media keys.
 +
 +
; Pages specific to certain laptop types
 +
* See [[:Category:Laptops]] and its subcategories for pages dedicated to specific models/vendors.
 +
* [[Asus_G1#The_Lapsus_daemon_.26_KDE_applet|Lapsus]] is a set of programs providing easy access to many features of various laptops. It currently supports most features provided by asus-laptop kernel module from ACPI4Asus project, such as additional LEDs, hotkeys, backlight control etc. It also has support for some IBM laptops features provided by IBM ThinkPad ACPI Extras Driver and NVRAM device.
 +
* Battery tweaks for ThinkPads can be found in [[TLP]] and the [[tp_smapi]] article.
 +
* [[Acer Aspire One#acerhdf|acerhdf]] is a kernel module for controlling fan speed on Acer Aspire One and some Packard Bell Notebooks.
 +
 +
; External resources
 
* [http://www.linux-on-laptops.com/ http://www.linux-on-laptops.com/]
 
* [http://www.linux-on-laptops.com/ http://www.linux-on-laptops.com/]
 
* [http://www.linlap.com/ http://www.linlap.com/]
 
* [http://www.linlap.com/ http://www.linlap.com/]

Revision as of 09:56, 17 October 2013

This page should contain links to pages needed for configuring a laptop for the best experience. Setting up a laptop is in many ways the same as setting up a desktop. However, there are a few key differences. Arch Linux provides all the tools and programs necessary to take complete control of your laptop. These programs and utilities are highlighted below, with appropriate tips tutorials.

Power management

Note: You should read the main articles Power Management and Power saving. Additional laptop-specific features are described below.

Power management is very important for anyone who wishes to make good use of their battery capacity. The following tools and programs help to increase battery life and keep your laptop cool and quiet.

Battery state

Reading battery state can be done in multiple ways. Classical method is some daemon periodically polling battery level using ACPI interface. On some systems, battery sends events to udev whenever it (dis)charges by 1%, this event can be connected to some action using udev rule.

ACPI

Battery state can be read using ACPI utilities from the terminal. ACPI command line utilities are provided via the acpi package. See ACPI modules for more information.

  • batterymon-cloneAUR is a simple battery monitor that sits in the system tray.
  • batti is a simple battery monitor for the system tray, similar to batterymon-clone. Unlike the former batti uses UPower, and if that is missing DeviceKit.Power, for it's power information.

Udev events

If your battery sends events to udev whenever it (dis)charges by 1%, you can use this udev rule to automatically suspend the system when battery level is critical, and thus prevent all unsaved work from being lost.

/etc/udev/rules.d/lowbat.rules
# Suspend the system when battery level drops to 2%
SUBSYSTEM=="power_supply", ATTR{status}=="Discharging", ATTR{capacity}=="2", RUN+="/usr/bin/systemctl suspend"

Likewise, the rule can be customized to perform other action on different status.

Testing events

One way to test udev rules is to have them create a file when they are run. For example:

/etc/udev/rules.d/98-discharging.rules
SUBSYSTEM=="power_supply", ATTR{status}=="Discharging", RUN+="/usr/bin/touch /home/example/discharging"

This creates a file at /home/example/discharging when the laptop charger is unplugged. You can test whether the rule worked by unplugging your laptop and looking for this file. For more advanced udev rule testing, see Udev#Testing rules before loading.

Suspend and Hibernate

Manually suspending the operating system, either to memory (standby) or to disk (hibernate) sometimes provides the most efficient way to optimize battery life, depending on the usage pattern of the laptop.

See the main article Suspend and Hibernate.

Hard drive spin down problem

Documented here

To prevent your laptop hard drive from spinning down too often:

/etc/udev/rules.d/75-hdparm.rules
ACTION=="add", KERNEL=="sd[a-z]", ATTR{queue/rotational}=="1", RUN+="/usr/bin/hdparm -B 254 /dev/$kernel"

See hdparm(8) for documentation of hdparm parameters. If you use pm-utils, you might be interested in these examples.

Screen brightness

See Backlight.

Touchpad

To get your touchpad working properly, see the Touchpad Synaptics page. Note that your laptop may have an ALPS touchpad (such as the DELL Inspiron 6000), and not a Synaptics touchpad. In either case, see the link above.

Hard disk shock protection

There are several laptops from different vendors featuring shock protection capabilities. As manufacturers have refused to support open source development of the required software components so far, Linux support for shock protection varies considerably between different hardware implementations.

Currently, two projects, named HDAPS and hpfallAUR (available in the AUR), support this kind of protection. HDAPS is for IBM/Lenovo Thinkpads and hpfall for HP/Compaq laptops.

Network time syncing

For a laptop, it may be a good idea to use Chrony as an alternative to NTPd to sync your clock over the network. Chrony is designed to work well even on systems with no permanent network connection (such as laptops), and is capable of much faster time synchronisation than standard ntp. Chrony has several advantages when used in systems running on virtual machines, such as a larger range for frequency correction to help correct quickly drifting clocks, and better response to rapid changes in the clock frequency. It also has a smaller memory footprint and no unnecessary process wakeups, improving power efficiency.

See also

General
  • CPU Frequency Scaling is a technology used primarily by notebooks which enables the OS to scale the CPU frequency up or down, depending on the current system load and/or power scheme.
  • Display Power Management Signaling describes how to automatically turn off the laptop screen after a specified interval of inactivity (not just blanked with a screensaver but completely shut off).
  • Wireless Setup provides information about setting up wireless connection.
  • Extra Keyboard Keys describes configuration of Media keys.
Pages specific to certain laptop types
  • See Category:Laptops and its subcategories for pages dedicated to specific models/vendors.
  • Lapsus is a set of programs providing easy access to many features of various laptops. It currently supports most features provided by asus-laptop kernel module from ACPI4Asus project, such as additional LEDs, hotkeys, backlight control etc. It also has support for some IBM laptops features provided by IBM ThinkPad ACPI Extras Driver and NVRAM device.
  • Battery tweaks for ThinkPads can be found in TLP and the tp_smapi article.
  • acerhdf is a kernel module for controlling fan speed on Acer Aspire One and some Packard Bell Notebooks.
External resources