Laptop-mode

2010-09-06T19:07:57Z

AlexBiddle:

An often overlooked feature in 2.4.23+ and 2.6.6+ Linux kernels is the laptop-mode. It may be activated by writing a "5" into {{path|/proc/sys/vm/laptop_mode}}. Laptop-mode, when configured correctly, can make the kernel buffer disk activities for quite a long time and keep the harddisk spun down for most of the time to save power.

There is also a set of userland tools made to automatically manage all aspects of laptop-mode configuration according to the actual mode of operation (ac/battery-status). It is called [[laptop-mode-tools]] and you can install it in debian via apt-get or download it from [http://www.xs4all.nl/~bsamwel/laptop_mode/tools here].

Almost anything you need to know about laptop-mode can be read in your Linux kernel documentation at /usr/src/linux/Documentation/laptop-mode.txt 
If you can not find this file on your laptop, then go and get yourself the latest kernel sources.

{{NOTE|The use of Laptop-mode and laptop-mode-tools is not recommended in SuSE Linux. The supplied <tt>powersaved</tt> already takes care of everything regarding power saving}}
{{NOTE| Laptop-mode is disabled by default on Ubuntu 6.10 and later. See [http://samwel.tk/laptop_mode/packages/ubuntu here] for more details}}.

=== Keeping the disk in the stand-by state ===

Laptop-mode is only effective if one avoids spinning up the disk for frivoulous reasons. What will spin a disk up is dependent on the HD firmware, but unfortunately most will spin up on just about every command. To add insult to injury, ATA/SATA pass-through commands are not logged through the {{path|/proc/sys/vm/block_dump}} facility, and thus invisible to tools like '''lm-profiler'''.

{{HINT|The '''lm-profiler''' tool from laptop-mode-tools can be used to list all processes doing normal disk access.}}

In systems where the HD spins up too easily, the "'''hddtemp'''" daemon will wake up the disk every minute, and must thus be disabled for power management to be effective. The "'''smartd'''" daemon is also an offender, but fortunately its default configuration issues commands to the HDs only every 30 minutes.

{{HINT|smartd can be configured to never issue commands to the disk if it is in the sleep or standby states, through the use of option "'''-n standby,q'''". The "''',q'''" is needed to supress syslog messages.}}

=== Hard drive noise using laptop-mode ===

The use of laptop-mode can cause a recurrence of the bug https://bugs.launchpad.net/ubuntu/+source/acpi-support/+bug/59695 known to affect Ubuntu distributions, which causes the spindle of the hard drive to be parked too frequently. This is caused by laptop-mode setting the Advanced Power Management feature of the hard drive in /etc/laptop-mode/laptop-mode.conf.

Ubuntu is not completely at fault, as the hard drive manufacturer should set an appropriate graduation between hard drive longevity and power saving using a value between 1 and 255. (more information can be found in the hdparm manual page under the -B flag).

Values up to 127 can cause unacceptable noise and wear of a hard drive (for more information on Load_Cycle_Counts and hard drive wear, see above bug report). An acceptable balance can be found using hdparm:

sudo hdparm -B 254 /dev/sdX

This value can then be entered into /etc/laptop-mode/laptop-mode.conf, first ensuring laptop-mode is set to control hdparm...

CONTROL_HD_POWERMGMT=1

...then by changing the default values:

BATT_HD_POWERMGMT=254
LM_AC_HD_POWERMGMT=254
NOLM_AC_HD_POWERMGMT=254

[[Category:Glossary]]

Category:Edge 13"

2010-08-31T15:27:38Z

AlexBiddle: /* (K)Ubuntu 10.04 LTS */

__NOTOC__
{| width="100%"
|style="vertical-align:top" |
<div style="margin: 0; margin-right:10px; border: 1px solid #dfdfdf; padding: 0em 1em 1em 1em; background-color:#F8F8FF; align:right;">
=== ThinkPad Edge 13" Series ===
This page gives an overview of all ThinkPad Edge 13" Series related topics. The Edge 13" exists both in a Intel and AMD processor model.

=== ThinkPad Edge 13" (Intel) ===
==== Machine Type ====
* 0196
==== Standard Features ====
* [[Intel Core 2 Duo (Penryn)|Intel® Core™2 Duo processor]] SU7300 (1.3GHz, 3MB L2)
* [[Intel Graphics Media Accelerator 4500MHD]]
* 13.3" [[TFT display]] with 1366x768 (HD) resolution with LED backlight
* 2 or 3GB [[PC3-8500]] memory standard upgradable to 4GB
* One of the following storage options
** 250GB 5400rpm 2.5" SATA HDD
** 320GB 7200rpm 2.5" SATA HDD
* [[Realtek Gigabit Ethernet (10/100/1000)]]
* Intel HD Audio with a [[CX20582]] codec
* [[MiniPCI Express slot]] 1 with one of the following:
** [[Intel Centrino Wireless-N 1000]]
** [[Intel Centrino Advanced-N + WiMAX 6250]]
* [[ThinkPad_Bluetooth_with_Enhanced_Data_Rate_(BDC-2.1)|Bluetooth]] on select models
* 0.3MP [[Integrated camera]]
* [[UltraNav]] (TrackPoint / Touchpad combo)
* Multicard reader 5-in-1 (MMC, MS, MS Pro, SD, SDHC)

=== Distribution Support ===

==== (K)Ubuntu 10.04 LTS ====

(K)Ubuntu 10.04 LTS supports this model out-of-the-box, including 3D desktop effects, hibernate, built-in webcam and wireless.

The combined headphone/microphone socket, however does not. As per https://bugs.launchpad.net/ubuntu/+source/linux-backports-modules-2.6.32/+bug/549289/comments/4 you need to add the line 
<tt>options snd-hda-intel model="olpc-xo-1_5"</tt> to the end of {{path|/etc/modprobe.conf/alsa-base.conf}}

The 13" model has no optical drive, so you must use something like usb-creator to put the ISO image of the LInux distribution on a (1 gig or larger) USB stick, then boot from that. 
There are more details on this at https://help.ubuntu.com/community/Installation/FromUSBStick

There does not seem to be a way to update the BIOS from Linux.

The package laptop-mode-tools may cause the spindle on the hard drive to be parked too frequently, causing an audible click as per https://bugs.launchpad.net/ubuntu/+source/acpi-support/+bug/59695. This can be solved by making sure {{path|/etc/laptop-mode/laptop-mode.conf}} is set to control hard disk power management 
<tt>CONTROL_HD_POWERMGMT=1</tt> 

And by changing the default hard disk management to 254, as per the workaround in the bug report. 
<tt>BATT_HD_POWERMGMT=254</tt> 
<tt>LM_AC_HD_POWERMGMT=254</tt> 
<tt>NOLM_AC_HD_POWERMGMT=254</tt> 

This number can be tuned to an acceptable Load_Cycle_Count by using hdparm with sudo 
<tt>sudo hdparm -B 254 /dev/sdX</tt>

==== OpenSUSE 11.3 ====

OpenSUSE 11.3 supports this model out-of-the-box, including 3D desktop effects, hibernate, built-in webcam and wireless.

The combined headphone/microphone socket and the built-in microphone, however do not.
A workaround is to add the following line at the beginning of {{path|/etc/modprobe.d/50-sound.conf}}: 
<tt>options snd-hda-intel model=olpc-xo-1_5</tt>

=== ThinkPad Edge 13" (AMD) ===
==== Machine Type====
* 0197
==== Standard Features ====
* [[AMD Athlon Neo X2]] Dual-Core processor L325 (1.5GHz, 1MB L2)
* [[ATI Mobility Radeon HD 3200]]
* 13.3" [[TFT display]] with 1366x768 (HD) resolution with LED backlight
* 2, 3 or 4GB [[PC2-5300]] memory standard
* 250GB or 320GB 5400rpm 2.5" SATA HDD
* [[Realtek Gigabit Ethernet (10/100/1000)]]
* HD Audio with a [[CX20582]] codec
* [[MiniPCI Express slot]] 1 with the following:
** [[ThinkPad 11b/g/n Wireless LAN Mini-PCI Express Adapter II]]
* 0.3MP [[Integrated camera]]
* [[UltraNav]] (TrackPoint / Touchpad combo)
* Multicard reader 5-in-1 (MMC, MS, MS Pro, SD, SDHC)
</div>
|style="vertical-align:top" |
[[Image:ThinkPadEdge13.jpg|ThinkPad Edge 13"|300px]]
|}

[[Category:Edge]]

ThinkWiki - User contributions [en]

Laptop-mode

Category:Edge 13"