[ltp] Battery life T61 - hints/tips welcome

Thomas Adam linux-thinkpad@linux-thinkpad.org
Wed, 12 Nov 2008 22:36:53 +0000


Hello all,

Given the recent thread this month about battery saving advice, I took
some of that information away with me, and decided to give it a go
myself for my T61.  Unfortunately, whether it is just me or not, but
none of what I am trying is seeming to make any difference whatsoever
-- my battery life is still under two hours regardless of any
suggestions I might have tried.

I am assuming though, based on most other people's trials and
tribulations this isn't the case, and given the proper instruction
have been able to increase their battery life to three hours plus --
so I hope my expectations on this aren't too unreasonable, although I
hope someone will point them out to me if they are.  :)

So far, I have installed and ran powertop, and implemented its
suggestions.  I built a lot of these into a shell script, the guts of
which are here (although I stole^H^H^H^Hcopied this script from
Theodore Tso):

#!/bin/sh
modprobe lp ; sleep 1; rmmod lp parport_pc parport
iwpriv eth1 set_power 5
modprobe ehci-hcd ; modprobe uhci-hcd; sleep 1; rmmod ehci-hcd uhci-hcd
killall -STOP multiload-applet-2 cpufreq-applet
echo disable > /proc/acpi/ibm/bluetooth
rmmod 8250 serial_core nsc_ircc irda crc_ccitt usb_storage nls_utf8
nls_cp437 vfat  fat sg
ethtool -s wlan0 wol d
echo 1500 > /proc/sys/vm/dirty_writeback_centisecs
echo 1 > /sys/devices/system/cpu/sched_mc_power_savings
for i in /sys/class/scsi_host/*/link_power_management_policy; do
   echo min_power > $i
done
for i in `echo /sys/bus/pci/drivers/iwlagn/*/power_level`; do
   echo 5 > $i
done
for i in cron atd ntp uml-utilities timidity ; do
   /etc/init.d/$i stop
done


Note that dispite running this script, my wattage is still high -- at
around 18 or so.  I also don't run or use laptop-mode-tools -- I seem
to recall reading somewhere that it's damaging in the long term,
although again someone with more experience should tell me otherwise.

Having tested the above script on nothing but a running battery, I can
confirm I am getting just over two hours of battery time.

Any tips, much appreciated.

-- Thomas Adam