Intel's PowerTOP Extends Linux Battery Life

DuracellFan writes "Intel recently released its PowerTOP utility, which builds on work done by kernel developers to make the Linux kernel power-efficient. PowerTOP gives a snapshot of what apps are consuming the most power. The PowerTOP website also hosts patches for several Linux apps and the kernel. In the Linux.com article, lead PowerTOP developer Arjan van de Ven of Intel says that PowerTOP could soon show which applications keep the disk busy." Linux.com and Slashdot are both part of OSTG.

Comments

Linux does not consume power!

[anss123]

The hardware that runs it does! Typical Intel, trying to shift the blame.

:)

PowerTOP not for casual users

[zborro]

Of course this utility is very useful for developers and for Linux distributors.
For the average user it is a nightmare.

Re:Old Kernels

[VON-MAN]

Most people i know still run 2.4.x

On a laptop? Sorry, that's stupid.

It's not a bug, it's a feature (tm) !

[DrYak]

DEAR User,

Sorry but you're mistaken.

You actually discovered our latest feature.
You haven't read about it yet, because we were developing and testing it until very recently, and we didn't want to speak to early about it.

We, as developers conscious of their travelling users, that have so much time that they need to work as they are in the train, have though of YOU !

As such we present you our latest feature :
WE GIVE YOU THE POSSIBILITY TO COOK YOUR DINNER ON YOUR LAPTOP (so you can do even more important things during the time you're commuting, which will leave you more free time when you reach your destination !)

Alternatively, you can also use our application on your laptop as AN INCREDIBLE AND COMPACT LAP-WARMER !!! For all those long commute during winter.
(DISCLAIMER : Warning, do not use with Batteries manufactured by Sony).

Thank you, wish you enjoy our brand new features.

- The Dev team.

Laptops??? What about my server farm?

[mpapet]

C'mon what are we talking about here, a few minutes? AFAIK, better power savings comes through a good acpi config, which I don't see a whole lot of discussion on.

My guess is where this kind of thing would make a dollars/cents difference is in the NOC. But this kind of detail isn't very sexy or very high on most NOC operators radar.

How about hours?

[eddy]

Success Stories

"With PowerTOP, I managed to increase the battery life of my Panasonic R4 laptop from 4 to almost 7 hours" -- Keith Packard, Principal Engineer at Intel

Guess you could accuse him of bias...

Re:How about hours?

[eddy]

If you just read the site (it's very small) you'll see that there are many no-obvious things you can detect with it. I personally do however consider it primarily a developer tool, but that might change. But even non-coding users can find out that the CDROM automounting polling is waking the CPU a lot, and disable that in battery mode, etc.

Re:Old Kernels

[diegocgteleline.es]

Most people i know still run 2.4.x and Slackware still ships with 2.4 as default.

Slackware users don't know people. Stop lying! It's just yourself who runs 2.4, right?

Re:Useless

[Andy Dodd]

Wrong.

Can they fix the application? Yes. See the list of numerous patches to various "notorious" offenders.

Before you comment about patches being too difficult to apply - in nearly all cases those patches have been sent upstream and are being integrated into the app by the developers of that app. The end result is that while in the short term, PowerTOP benefits only power users who can patch and compile from source, it has enabled identification of offending sections of application code so that the application authors can fix it. (For example, the next release of Pidgin will come with numerous fixes for behavior found with PowerTOP.)

In short:
PowerTOP has almost no benefit for the "normal" user in the short term
PowerTOP has quite a lot of potential benefit for the "power" user
PowerTOP has the ability to enable application developers to make optimizations that help the "normal" users some time down the line (depending on application/distribution release cycles), thus PowerTOP has great benefit for "normal" users in the long term.

Can they stop the application? Usually not, but there are some notorious offenders that are "on by default" that most users don't benefit too much from, and would rather temporarily or permanently disable to increase battery life. (See Beagle for example).

My results

[rg3]

I have just tried the thing. I achieved less than 20 wakeups per second when my KDE desktop is idle, but learned a few things on the way. For example, by using a USB mouse instead of the laptop touchpad I am unable to reach state C3. It's reached when I unplug the mouse. I suppose I'll have to put up with it, because I can't stand the touchpad. On the other hand, I used to have KMail opened in a second virtual desktop to check for mail every 60 seconds, but I discovered that the bastard was waking up twice a second for no apparent reason, so I have started to use Korn (the mail check systray thingy). There are still some applications that wake up for no reason apparently. For example, why does klipper wake up once per second? And the same goes for kwrapper. I don't even know what that is. Can somebody explain in detail? Google isn't very specific about it.

But yes, the application is very interesting. Sorry, Intel, my laptop has an AMD processor. The next one will be Intel, with an Intel graphics card and an Intel wireless card. I promise. :P

Re:How stable is CONFIG_NO_HZ?

[Ant P.]

I'm using NO_HZ on my P4 desktop. It was horrible in old patches, but the version in the mainline kernel (>= .20) is solid as a rock.

I gave the powertop thing a try the other day. Seems the worst offender on my machine is MPD, even when it's not doing anything.

According to this utility ...

[PPH]

... its a tie between my USB-powered arc welder and all the kewl blue LEDs.