Linux is not good at power management. True or False?

I often hear that Linux is not as good as Windows Vista/Windows 7 in terms of power management. Essentially that all things being equal with only the OS being different, Linux will give me less battery time than Vista or Win 7. I hear the same argument with heat generation. Is this true? Can we have a discussion on this. If Windows does infact have have better power management and offers battery life, that would be a serious reason for me to stay with Windows on the laptop.

 

true in my opinion, although the gap is closing.

1 thing that bothers me about linux power management is the Load_Cycle_Count issue on laptops on AC power.

 

Agreed, I consider Windows better at power mangement.
Much better at easy power management and superior at undervolting.
The latter is where Windows shines, it's simply much much easier.
Sofar I haven't been able to patch/match any main Linux distro to Windows regarding battery life.

 

I don't think Windows has better power management exactly, and if so not by as much as it seems. Windows handles power schemes better, if you set those up, they work great.
Also I get more battery life in KDE 4 with Powerdevil than in Gnome.

 

The Load_Cycle_Count is easy to manipulate. The main problem is in the little things like dynamic USB suspension, sound card sleep state, and wireless card signal strength control. It all really depends on the hardware. I believe that linux has a much greater potential for energy savings due to having relatively few background processes and more efficient threading. But the clincher is hardware support.

In short, linux has worse power management than Windows on MOST hardware. However, there are those few in which it has a noticeable advantage in power management over Windows. The Thinkpad T41, I believe, is one of these, but don't quote me on that.

 

True, but only in the desktop market. Even in the desktop market, the gap is becoming smaller and smaller, as popular distros like Ubuntu can often meet or surpass XP power management if in the right hands. The Linux implementation of ACPI services is still shaky atm, and has even caused serious problems for system stability in Ubuntu in the past.

In the server niche, however, power management does matter (contrary to most beliefs), and Linux reigns supreme in that regard.

 

I agree with Bog. In gigantic SMP server systems, linux wins hands down. It even lets you direct exactly how much of the system is in use while it's online. I doubt very much that Windows will ever get to touch something with more than 1000 processors.

 

Depending on your hardware Windows may or may not have better power management.
But with tweaking, you can usually get Linux's power consumption pretty low. It's just not that way out of the box the way it is with Windows.
My Inspiron 4100 gets almost 8 hours of battery life in Windows XP, but only about 5 in Xubuntu (both with no tweaks). Even after tons of tweaks, I can't get Xubuntu to even 6 hours.
On the other hand, my Thinkpad X31 gets about 2.5 hours of battery life in both XP and Xubuntu out of the box... and after tweaking, I can get Xubuntu to about 3.5 hours, while I can't get XP even to 3.
So I am going to say hardware dependent (mainly if your CPU supports scaling governors, the driver you use for your video, and what hardware drivers you can unload when you're not using them)

 

It also depends on what kind of architecture you're talking about... low power architecture is making serious headway with stuff like Moblin (and its collaboration with UNR).

Here's a link to a recent power management mini-summit, there are some notes from previous ones but none yet from the latest: http://www.linuxsymposium.org/2009/view_abstract.php?content_key=107

Also check out lesswatts.org

 

I have an Acer 5570 laptop that does get a bit better power management with Ubuntu than XP. I had to search through the Ubuntu forums to find how to set the cycle count properly when I installed 8.04 LTS. The problem is that I do not remember exactly how I did it? Usually I write the process down for future reference, but this time I had gotten so frustrated that I slipped up and forgot to do so...?

Once I got rid of Vista this Acer runs a lot quicker and the constant nag screens are finally gone. PTL!!

 

I think you are referring to these commands?

Disable spindown:

Code:

sudo hdparm -B 128 /dev/sda

Disable power management altogether:

Code:

sudo hdparm -B 255 /dev/sda

Check power and load cycle counts:

Code:

sudo smartctl -a /dev/sda | grep -i cycle_count

 

Some very intersting posts. I will take your word on the larger servers and such, but the machines I was talking about are Ultra portable machines with regular and Ultra low voltage processors and netbooks(intel atom CPU). Both of these categories of machines need very good battery life, even more so than other laptops. I myself have a Thinkpad X200 Ultra portable laptop with a regular voltage Core 2 Duo P8400 CPU. You can use that as the reference for the purposes of this thread. I am using Vista Business 32 SP1 on my X200and I love Linux, but Linux is out on the laptop if I can't get equal or better battery life as my Vista install or Win 7.

 

A more favourable way to handle the load cycle count is to check whether the HDD you use, uses agressive power management features.
I found out my Hitachi TravelStar has this and this accounted mainly for the load cycle count.
When I contacted Hitachi, they advised me to use their software to change settings. Done accordingly, this handled the load cycle count.
Check the Hitachi information in this thread.

 

I run eeebuntu on my eeepc and it comes with a control panel that includes crude power management options. Not great, but it does help.

I dunno if you guys caught WattOS on distrowatch.com the other day but it is an ubuntu-based OS that adds power management tools.

It's in beta right now but it seems like that lxde/openbox version would be perfect for a netbook.


wattOS - wattOS - Gnome based user interface with wattOS specific customizations

wattOS - Milliwatt - XFCE based user inferface with wattOS specific customizations

wattOS - Microwatt - Openbox - LXDE - and other lightweight components that make up the user interface and windowing.

wattOS - Substation - server version - no gui - with webmin and console capability

 

Lot of good posts. But overall it seems that Vista/Win7 are still better at power management on the laptop(giving me more battery life) then Linux, but Linux is improving. Correct?

 

As much as I like Linux, I would say that that is a fairly accurate summary of the state of it's power management relative to the competition.

 

Thats too bad. I really love Linux as well. I have Debian on my desktop and my Thinkpad T61p(will be for sale soon) and it works great on both machines. I didn't think of battery life/power management much for my T61p since I knew it wouldn't be getting great battery life with its powerful GPU so I used it plugged in most of the time. I just got a Thinkpad X200 Ultra portable specifically for its small size, weight and awesome battery life and it looks like I will stay with Vista on it. I am not willing to compromise battery life to use Linux. I will stay with Linux on my desktop and Windows on my laptops .

From my perspective the inferior power management will hurt Linux on the popular netbooks and Ultraportables, since one of their main selling points is battery life.

 

Yeah, Linux works beautifully on ThinkPads, which is why it is such a joy to run Ubuntu or whatever distro I please on my good old T42. But, the tight integration required by most other laptop models simply isn't provided by the manufacturers (with the other exception being Dell).

So for now, I don't run Linux on my laptops; I do not consider it to be as good a mobile operating system unless it has been extensively customized and integrated with hardware by the manufacturer (often, this is left to the user; ex, having to install ndiswrapper to get wireless working is "unacceptable" but necessary). I do, however, run Linux on my desktops.

That said, Windows (Vista) does have much better power management. but it is not much better in other equally important criteria as a mobile OS in that it's wireless management is utterly retarded; the interface has been fixed, but it still has many problems:

- wireless frequently won't connect or thinks it is connected to an old network when the machine has been resumed from sleep
- wireless profile management frequently creates copies of a network; ex, uw-wireless1, uw-wireless2, ... uw-wireless21, etc.

Yes, all the major operating systems out there (with the possible exception of OSX, since I haven't used it) need work on their mobile services. They are all broken in one way or another.

 

Thats strange. I don't have any of these problems with Vista's wireless management. It connects just fine to my network and has never dropped on me. I don't get any duplicates or any problems after sleep. I actually think it works pretty good, but it could connect to my network a little faster.

 

Thanks ALLurGroceries! I cut and pasted those command to a document for future use so I that I will not forget them again!