Major power concern

Richard A. Smith richard at
Fri Oct 3 12:24:42 EDT 2008

greebo wrote:

>> To determine if it is a battery problem follow the instructions for  
>> using opc-pwr-log. (This should be pre-installed on 757).
>> The instructions are at:
> Will do and will post results.

You may want to modify this script a bit.

The delay method I uses the clock and a sleep 2 loop rather than just a 
sleep x command for the delay.  The reason is so I can delay properly 
across an idle-suspend.  The sleep(2) loop may not be the best for this 
sort of measurement.  Each reading involved lots of EC commands.

Its probably a good idea to replace the 'wallclock_delay' with 'sleep'. 
  Idle-suspend is off in those builds so the wallclock feature is not 

By default DELAY is set to 10 seconds but if you really wanted a sense 
of the idle power you can increase that to 60 or even longer.  The ACR 
reading will track the over all power used accurately regardless of the 
delay time.  Smaller delays are good if you want to try and catch some 

Richard Smith  <richard at>
One Laptop Per Child

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