Liunx power consumption on laptops -- Enormous progress in the last few months

Liunx power consumption on laptops -- Enormous progress in the last few months

[Arjan van de Ven]

Hi,

with all the tickless and other goodies going into the kernel in the 
last few months, there is a lot of hope that this helps Linux reduce 
power consumption... and the good news is that it does... once you fix 
some bugs and fix a bunch of userspace applications.

While it's hard to show "one size fits all" number/percentage, we took 
a bog standard Lenovo T61 laptop (no vendor preference, they just were 
the first one to deliver a model with the latest Intel chipset to our 
cubes) and measured the effect. The baseline we used was a 32 bit 
Fedora 7 installation; note that this already has the tickless kernel, 
but is lacking several of the key bugfixes that came afterwards.

We've put our measurements in a graph at

http://ww.linuxpowertop.org/results.php

With kernel fixes and features, the power consumption of this laptop 
went from 21.06 Watts to 18.25 Watts; with 2 additional userspace 
fixes the power consumption ended up at 15.5 Watts.

(Don't worry that this is the end of it; there's more stuff in the 
various project pipelines, and we'll keep measuring the progress over 
time)


All in all, personally I'm very happy to see Linux making such a huge 
step forward with tickless and can't wait for this step to be 
available in all distros and for all architectures...

Greetings,
    Arjan van de Ven

Re: Liunx power consumption on laptops -- Enormous progress in the last few months

[Chuck Ebbert]

On 07/05/2007 03:58 PM, Arjan van de Ven wrote:
> While it's hard to show "one size fits all" number/percentage, we took a
> bog standard Lenovo T61 laptop (no vendor preference, they just were the
> first one to deliver a model with the latest Intel chipset to our cubes)
> and measured the effect. The baseline we used was a 32 bit Fedora 7
> installation; note that this already has the tickless kernel, but is
> lacking several of the key bugfixes that came afterwards.
> 
> We've put our measurements in a graph at
> 
> http://ww.linuxpowertop.org/results.php
> 
> With kernel fixes and features, the power consumption of this laptop
> went from 21.06 Watts to 18.25 Watts; with 2 additional userspace fixes
> the power consumption ended up at 15.5 Watts.
> 

Where is the ondemand-fix.patch? I can't find any link to it.

Re: Liunx power consumption on laptops -- Enormous progress in the last few months

[Arjan van de Ven]

Chuck Ebbert wrote:
> On 07/05/2007 03:58 PM, Arjan van de Ven wrote:
>> While it's hard to show "one size fits all" number/percentage, we took a
>> bog standard Lenovo T61 laptop (no vendor preference, they just were the
>> first one to deliver a model with the latest Intel chipset to our cubes)
>> and measured the effect. The baseline we used was a 32 bit Fedora 7
>> installation; note that this already has the tickless kernel, but is
>> lacking several of the key bugfixes that came afterwards.
>>
>> We've put our measurements in a graph at
>>
>> http://ww.linuxpowertop.org/results.php
>>
>> With kernel fixes and features, the power consumption of this laptop
>> went from 21.06 Watts to 18.25 Watts; with 2 additional userspace fixes
>> the power consumption ended up at 15.5 Watts.
>>
> 
> Where is the ondemand-fix.patch? I can't find any link to it.

just click on it in the graph ;_

it's also http://www.linuxpowertop.org/patches/ondemand-fix.patch 
(which is submitted already to the maintainers)

Re: Liunx power consumption on laptops -- Enormous progress in the last few months

[Dave Jones]

On Fri, Jul 06, 2007 at 09:35:24AM -0700, Arjan van de Ven wrote:

 > > Where is the ondemand-fix.patch? I can't find any link to it.
 > 
 > just click on it in the graph ;_
 > 
 > it's also http://www.linuxpowertop.org/patches/ondemand-fix.patch 
 > (which is submitted already to the maintainers)

Should be in cpufreq.git (and thus, -mm) too, waiting for .23 to open up.

	Dave

-- 
http://www.codemonkey.org.uk

Re: Liunx power consumption on laptops -- Enormous progress in the last few months

[Chuck Ebbert]

On 07/06/2007 12:35 PM, Arjan van de Ven wrote:
>> Where is the ondemand-fix.patch? I can't find any link to it.
> 
> just click on it in the graph ;_
> 
> it's also http://www.linuxpowertop.org/patches/ondemand-fix.patch (which
> is submitted already to the maintainers)
> 

Ah, OK, that one just went into the latest Fedora 7 kernel.

Re: Liunx power consumption on laptops -- Enormous progress in the last few months

[Bill Davidsen]

Chuck Ebbert wrote:
> On 07/06/2007 12:35 PM, Arjan van de Ven wrote:
>>> Where is the ondemand-fix.patch? I can't find any link to it.
>> just click on it in the graph ;_
>>
>> it's also http://www.linuxpowertop.org/patches/ondemand-fix.patch (which
>> is submitted already to the maintainers)
>>
> 
> Ah, OK, that one just went into the latest Fedora 7 kernel.
> 
All this information makes it obvious that even though upgrades are 
painful (given slow laptop disks, *really* painful), it looks as if 
there are major benefits to be gained.

Thanks for sharing the information.

As improved as USB drivers are, I assume that unloading the drivers is 
still desirable if no USB hardware is in use.

-- 
Bill Davidsen <davidsen@tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot

Re: Liunx power consumption on laptops -- Enormous progress in the last few months

[Valdis.Kletnieks]

[-- Attachment #1: Type: text/plain, Size: 914 bytes --]

On Fri, 06 Jul 2007 13:02:10 EDT, Dave Jones said:
> On Fri, Jul 06, 2007 at 09:35:24AM -0700, Arjan van de Ven wrote:
> 
>  > > Where is the ondemand-fix.patch? I can't find any link to it.
>  > 
>  > just click on it in the graph ;_
>  > 
>  > it's also http://www.linuxpowertop.org/patches/ondemand-fix.patch 
>  > (which is submitted already to the maintainers)
> 
> Should be in cpufreq.git (and thus, -mm) too, waiting for .23 to open up.

Somebody should fix http://ww.linuxpowertop.org/known.php then, it says:

"The kernels ondemand CPU frequency management function currently has a
high-frequency timer that samples to see if the CPU is idle. Intel fixed this
and the patches to the kernel to effectively remove this timer are included in
Linus' tree as of 2.6.22-rc1."

which confused me no end when I was looking at this stuff and wondering why
it was in the -mm tree if Linus already picked it up. :)

[-- Attachment #2: Type: application/pgp-signature, Size: 226 bytes --]

Re: Liunx power consumption on laptops -- Enormous progress in the last few months

[Dave Jones]

On Mon, Jul 09, 2007 at 05:42:14PM -0400, Valdis.Kletnieks@vt.edu wrote:
 > On Fri, 06 Jul 2007 13:02:10 EDT, Dave Jones said:
 > > On Fri, Jul 06, 2007 at 09:35:24AM -0700, Arjan van de Ven wrote:
 > > 
 > >  > > Where is the ondemand-fix.patch? I can't find any link to it.
 > >  > 
 > >  > just click on it in the graph ;_
 > >  > 
 > >  > it's also http://www.linuxpowertop.org/patches/ondemand-fix.patch 
 > >  > (which is submitted already to the maintainers)
 > > 
 > > Should be in cpufreq.git (and thus, -mm) too, waiting for .23 to open up.
 > 
 > Somebody should fix http://ww.linuxpowertop.org/known.php then, it says:
 > 
 > "The kernels ondemand CPU frequency management function currently has a
 > high-frequency timer that samples to see if the CPU is idle. Intel fixed this
 > and the patches to the kernel to effectively remove this timer are included in
 > Linus' tree as of 2.6.22-rc1."
 > 
 > which confused me no end when I was looking at this stuff and wondering why
 > it was in the -mm tree if Linus already picked it up. :)

There were two sets of fixes to ondemand.  The first round did in fact
go into .22rc1  The others I deemed too late in the cycle to go into .22
(Though they have been flawless, so if there was enough demand (ha!) we could
 even push them to -stable once they're in mainline).

	Dave

-- 
http://www.codemonkey.org.uk

Re: Liunx power consumption on laptops -- Enormous progress in the last few months

[Pavel Machek]

On Mon 2007-07-09 13:55:05, Bill Davidsen wrote:
> Chuck Ebbert wrote:
> >On 07/06/2007 12:35 PM, Arjan van de Ven wrote:
> >>>Where is the ondemand-fix.patch? I can't find any link to it.
> >>just click on it in the graph ;_
> >>
> >>it's also http://www.linuxpowertop.org/patches/ondemand-fix.patch (which
> >>is submitted already to the maintainers)
> >>
> >
> >Ah, OK, that one just went into the latest Fedora 7 kernel.
> >
> All this information makes it obvious that even though upgrades are 
> painful (given slow laptop disks, *really* painful), it looks as if 
> there are major benefits to be gained.
> 
> Thanks for sharing the information.
> 
> As improved as USB drivers are, I assume that unloading the drivers is 
> still desirable if no USB hardware is in use.

That should be no longer neccessary, IIRC.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

PCI devices power management, w/o sysfs? [Was: Re: Liunx power consumption on laptops ...]

[Richard Mittendorfer]

Greetings *!

I'm looking for a way to disable (PM low power mode) some devices I
rarely/never use on my laptop to save some more power. With 2.6.17,
IIRC, I was able to echo -n 2 > /sys/bus/pci/../power to put things
into low power mode. (I don't know if it ever worked, but at least it
looked like it did.)

..-2.6.22(-ck1) w/ CONFIG_PM_SYSFS_DEPRECATED doesn't let me change this
state. evident :) -----------------^^^^^^^^^^

Is there a proper way to do this (setpci, if I'd know the registers)?
Is it gone/going inside drivers (like USB_SUSPEND) and I don't have to
worry?

I currently don't load the modules in question - but I'm not sure if it
helps, as they might already be powered on by PCI initialization/BIOS
(/sys/bus/pci/../state cats "0").

THX, ritch

Re: PCI devices power management, w/o sysfs? [Was: Re: Liunx power consumption on laptops ...]

[Arjan van de Ven]

On Wed, 2007-07-11 at 14:42 +0200, Richard Mittendorfer wrote:
> Greetings *!
> 
> I'm looking for a way to disable (PM low power mode) some devices I
> rarely/never use on my laptop to save some more power. With 2.6.17,
> IIRC, I was able to echo -n 2 > /sys/bus/pci/../power to put things
> into low power mode. (I don't know if it ever worked, but at least it
> looked like it did.)
> 
> ..-2.6.22(-ck1) w/ CONFIG_PM_SYSFS_DEPRECATED doesn't let me change this
> state. evident :) -----------------^^^^^^^^^^
> 
> Is there a proper way to do this (setpci, if I'd know the registers)?
> Is it gone/going inside drivers (like USB_SUSPEND) and I don't have to
> worry?
> 
> I currently don't load the modules in question - but I'm not sure if it
> helps, as they might already be powered on by PCI initialization/BIOS
> (/sys/bus/pci/../state cats "0").

the real solution is to do it right in the driver.
Using a sysfs "whack behind the drivers back" method is just a disaster
waiting to happen; it cannot be done reliable (for example, without
knowledge of what you're doing, an application that just whacks all may
whack devices that have hw quirks and cannot deal with this, etc etc).


-- 
if you want to mail me at work (you don't), use arjan (at) linux.intel.com
Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org