[ltp] very high number of wakeups (and power consumption) on T60p

[Aidan Marks]

I noticed this last night when I was burning through battery while on an 
overseas flight even though I have almost all modules unloaded. a reboot 
fixed it temporarily, but it came back somehow.

gentoo T60 using thinkpad-sources - 2.6.24-thinkpad-r3.

Peter F. Patel-Schneider wrote:
> From: Theodore Tso <tytso@MIT.EDU>
> Subject: Re: [ltp] very high number of wakeups (and power consumption) on T60p
> Date: Wed, 27 Feb 2008 20:09:06 -0500
> 
>> On Wed, Feb 27, 2008 at 07:46:10PM -0500, Peter F. Patel-Schneider wrote:
>>> Has anyone run into problems with tens of thousands of wakeups that are
>>> unexplained in powertop?  This does appear to be real as battery drain
>>> does jump up about 30-40%.
>> There was a bug that was fixed in a very recent BIOS release for most
>> Thinkpad which caused interrupts to go wild if bluetooth was enabled
>> and the usb modules were loaded.  You might want to try updating your
>> BIOS to the very latest firmware and see if the problem goes away.
>> Another workaround if you can't upgrade your firmware right away is to
>> disable bluetooth using "echo disable > /proc/acpi/ibm/bluetooth".  
>>
>> If you depend on the Bluetooth interface, then your only option will
>> be to upgrade your BIOS.  :-0
>>
>> 						- Ted
> 
> This is not likely to be my problem, but thanks for the information.
> 
> I updated to the current BIOS (2.20 for T60p) and the problem persists.
> 
> Following /proc/interrupts doesn't lead to any culprits either.  Only
> about 100 interrupts per second are shown there, whereas I'm currently
> getting over 41 thousand wakeups-from-idle per second.
> 
> I guess that this leaves DMA activity as the prime suspect, even though
> I have the radios (WiFi and bluetooth) switched off.
> 
> peter