2014-01-06 21:11:18

by Pavel Machek

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Subject: Re: [QUERY] Power consumption on a 2013 MBP

On Tue 2013-12-31 15:24:00, Ramkumar Ramachandra wrote:
> Hi,
>
> On a 2013 Macbook Pro, Linux consumes 21W of power while OS X consumes
> just 9W. I found this very disturbing; Linux more than halves the
> battery life of the device. I checked to see that I wasn't running any
> especially power-hungry applications or drivers (using powertop). I'm
> using just one proprietary driver: the broadcom-wl wireless driver;
> otherwise, I'm running the stock 3.12 kernel from Arch's repositories.
>
> How do I figure out what is consuming power, and what can I do to help
> minimize consumption?

USB usually does that. Try rmmoding hcd(s). If that does not help, try
removing other modules. Oh and try without that broadcom-wl driver.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


2014-01-06 21:24:05

by Ramkumar Ramachandra

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Subject: Re: [QUERY] Power consumption on a 2013 MBP

Pavel Machek wrote:
> USB usually does that. Try rmmoding hcd(s). If that does not help, try
> removing other modules. Oh and try without that broadcom-wl driver.

Unused modules shouldn't consume so much power, no? I suspected
broadcom-wl, but removing it doesn't help. Instead of shooting in the
dark, is there some tool that I can use to figure out the culprits?

Thanks.

2014-01-06 21:36:32

by Pavel Machek

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Subject: Re: [QUERY] Power consumption on a 2013 MBP

On Tue 2014-01-07 02:47:18, Ramkumar Ramachandra wrote:
> Pavel Machek wrote:
> > USB usually does that. Try rmmoding hcd(s). If that does not help, try
> > removing other modules. Oh and try without that broadcom-wl driver.
>
> Unused modules shouldn't consume so much power, no? I suspected
> broadcom-wl, but removing it doesn't help. Instead of shooting in the
> dark, is there some tool that I can use to figure out the culprits?

"Should not". Exactly. Your machine should not consume 20W. It does,
so try rmmoding USB modules, and probably AHCI...

Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

2014-01-06 23:05:49

by Ramkumar Ramachandra

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Subject: Re: [QUERY] Power consumption on a 2013 MBP

Pavel Machek wrote:
> "Should not". Exactly. Your machine should not consume 20W. It does,
> so try rmmoding USB modules, and probably AHCI...

My system freezes if I remove modules like usbhci, ahci, ehci_hcd.

2014-01-07 00:27:39

by Pavel Machek

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Subject: Re: [QUERY] Power consumption on a 2013 MBP

On Tue 2014-01-07 04:35:04, Ramkumar Ramachandra wrote:
> Pavel Machek wrote:
> > "Should not". Exactly. Your machine should not consume 20W. It does,
> > so try rmmoding USB modules, and probably AHCI...
>
> My system freezes if I remove modules like usbhci, ahci, ehci_hcd.

Umm. Try harder. Like booting init=/bin/bash and not inserting them in
the first place.

--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

2014-01-07 10:33:42

by Ramkumar Ramachandra

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Subject: Re: [QUERY] Power consumption on a 2013 MBP

Ramkumar Ramachandra wrote:
> My system freezes if I remove modules like usbhci, ahci, ehci_hcd.

Correction: my input devices (keyboard, trackpad) depend on usbhci,
ehci_hcd, while libata and my hard disk drivers depend on ahci;
there's no way I can do without them. I'm trying to get VGA switcheroo
to work so I can switch to the onboard i915 graphics card in the hope
of saving power.

2014-01-07 12:24:16

by Pavel Machek

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Subject: Re: [QUERY] Power consumption on a 2013 MBP

On Tue 2014-01-07 16:03:00, Ramkumar Ramachandra wrote:
> Ramkumar Ramachandra wrote:
> > My system freezes if I remove modules like usbhci, ahci, ehci_hcd.
>
> Correction: my input devices (keyboard, trackpad) depend on usbhci,
> ehci_hcd, while libata and my hard disk drivers depend on ahci;
> there's no way I can do without them.

Ramdisk, scripts.

>I'm trying to get VGA switcheroo
> to work so I can switch to the onboard i915 graphics card in the hope
> of saving power.

That should indeed do the trick.x
Pavel

--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html