Powersaving Tips

Discussion in 'Linux' started by SlCKB0Y, Dec 7, 2008.

  1. SlCKB0Y

    SlCKB0Y

    Joined:
    Sep 13, 2008
    Messages:
    165
    Likes Received:
    0
    Location:
    Sydney, Australia
    So now we seem to have almost all hardware functioning as it should, I think the next major difference which needs to be addressed is powersaving. With my Xubuntu install, even with the power tweaks from the wiki, i'm still not getting anything close to the battery life that I saw under Linpus, or even Windows. There seems to be about a 20-30 minute difference and I would very much like to reduce this if possible.

    Does anyone have any sneaky tips for reducing your power consumption? And if so can you post your powertop results so we can all get some idea of what is possible?

    :)

    The lowest i've seen mine idle is around 8.7W. I'm sure this can be improved.
    Xubuntu 8.10
     
    SlCKB0Y, Dec 7, 2008
    #1
  2. SlCKB0Y

    2manydjs

    Joined:
    Jul 16, 2008
    Messages:
    300
    Likes Received:
    0
    Now that we have the cardreaders working, has someone tried the powersaving script again?

    Of course you can turn off unnecessary services, for example just one logger and one cron daemon and turn off BT and print services.

    At 8.7 watts I assume you have applied all the suggestions from the Ubuntu guide and you're using the ath5k WiFi driver. I've read somewhere that MadWifi is more power efficient than ath5k, is that true? Hopefully this news will give us an even better WiFi driver.

    Something I've been wanting to do for a while is start with a minimal server install and install my own desktop environment (gnome-core rather than ubuntu-desktop) from there. I have done this once before and it seems to be lighter and more importantly it was faster than a normal install. I did not check the battery life, but I do expect it should give an improvement.

    EDIT
    Code:
    scan_dev
    	if [ -f /sys/bus/usb/devices/1-5/power/level ]; then
    	   echo auto > /sys/bus/usb/devices/1-5/power/level
    	fi
    
    	if [ -f /sys/bus/usb/devices/5-5/power/level ]; then
    	   echo auto > /sys/bus/usb/devices/5-5/power/level
    	fi
    	sleep $time
    	acdc
    	if [ $PWRMODE -eq 1 ] ; then
    		d3e
    	fi
    Is this the only powersaving from the script? If so, we can just put this in rc.local as described in the guide, right?
     
    2manydjs, Dec 7, 2008
    #2
  3. SlCKB0Y

    2manydjs

    Joined:
    Jul 16, 2008
    Messages:
    300
    Likes Received:
    0
    One of the services I'm interested in disabling is GDM and then enable auto login. Perhaps this is the correct way.
     
    2manydjs, Dec 7, 2008
    #3
  4. SlCKB0Y

    2manydjs

    Joined:
    Jul 16, 2008
    Messages:
    300
    Likes Received:
    0
    Just read on the Arch forum that disabling the fan (acerfand) reduces the battery life, because the battery lasts longer when it's cooler..
    What do you guys think?
     
    2manydjs, Dec 11, 2008
    #4
  5. SlCKB0Y

    Issue313

    Joined:
    Oct 26, 2008
    Messages:
    17
    Likes Received:
    0
    Location:
    http://chris-aceraspireone.blogspot.com/
    ^^^Nonsense.

    The elephant in the room with the AAO is the graphics card. Lets break down power usage:

    CPU = 2.5 W
    Graphics chip = 6 W
    I/O controller =3.3W
    LCD = 3 W.
    SSD = 0.3 W
    Anyone have a figure for the wlan0?

    The card readers ... do they even use a measurable amount of power?

    See also
    http://www.randomprocess.ca/2008/09/23/ ... view-xp/4/
     
    Issue313, Dec 11, 2008
    #5
  6. SlCKB0Y

    tobiasboon

    Joined:
    Dec 6, 2008
    Messages:
    4
    Likes Received:
    0
    I would agree power saving should be next. Great work Sickboy many thanks for the 2.6.28 debs.

    One issue I've found is ACPI on the Aspire One for Linux is essentially broken since the EC/DSDT thingamabob is not talking to the OS. As I understand it the ACPI DSDT in the one is not standard ACPI (which WIndows is perfectly happy with since it was compiled with a windows compiler) we can't control fan wifi etc until ACPI is fixed. Having ACPI for the wireless means we can have notifiction when the kill switch is on/off.

    See : viewtopic.php?f=44&t=5329&start=0&st=0&sk=t&sd=a
    Anybody know "noda" or if there is anything the community can do to help him/her?

    Also, the acer-wmi ACPI module doesn't support the aspire one so SOL.

    I also keep finding this post http://linux.derkeiler.com/Mailing-List ... 04565.html which seems to imply something is happening in the 2.6.28 kernel to fix some acpi problems.

    There is also turning powersave on the snd intel sound.
    http://www.lesswatts.org/tips/misc.php
    * some people claim this cause problems shuttingdown/suspending.

    This site was pretty useful http://www.lesswatts.org/

    This seems like an achievable task if someone knows acpi/dsdt...
     
    tobiasboon, Dec 12, 2008
    #6
  7. SlCKB0Y

    2manydjs

    Joined:
    Jul 16, 2008
    Messages:
    300
    Likes Received:
    0
    Does Acer Linpus have the correct ACPI support? Or did they just tweak it hard enough to run light? If it does, could we start looking at what they did?

    Is there a powertop equivalent for Windows so we can see what to target for?
     
    2manydjs, Dec 13, 2008
    #7
  8. SlCKB0Y

    SlCKB0Y

    Joined:
    Sep 13, 2008
    Messages:
    165
    Likes Received:
    0
    Location:
    Sydney, Australia
    Ialways got a better battery time from linpus.

    hmmm, with wiki tweaks. unr image, my custom kernel, wifi on and screen at the lowest setting, im getting 8.2/8.3 w at idle. getting there.

    Next im replacing the wifi card with an intel one which actually can do power saving.
     
    SlCKB0Y, Dec 15, 2008
    #8
  9. SlCKB0Y

    exwannabe

    Joined:
    Dec 30, 2008
    Messages:
    42
    Likes Received:
    0
    Back to Stick's 8.7 number, is that a 110 or 150?

    I am at 8.1w at idle on the 110 w/o anything drastic. I have tried about everything I know (or can find via google) without much effect.

    One oddity I see is that gnome-power-manager goes insane when the power cord is pulled (on my Kubuntu build). For several minutes it is eating many CPU cycles causing a higher percentage of non C3/4 states, and more power. It's really obvious on powertop.

    I have tried several kernel config changes (starting with Stick's, but now with the -28 release) and see little variation.

    I don't have Limpus available to check out a few possibilities.

    1) Any chance the X config does something to cool off the driver chipset? [I have tried the suggestion of enabling compression, no detectable improvement].

    2) Is it possible they (the ACER Limpy team) dropped something into Fedora that we don't have?

    Is there a place to get one's hand on Limpy o check these out?
     
    exwannabe, Jan 1, 2009
    #9
  10. SlCKB0Y

    mattytee

    Joined:
    Nov 30, 2008
    Messages:
    112
    Likes Received:
    1
    Can someone list the whole shebang? There must be something I've missed.

    I'm running sickboy's awesome 2.6.28 on 8.10 umpc but I can only get it down to 8.7 watts on my AAO 110 (half-brightness, ath5k wifi).

    I am running every power saving tip I could find except the cardreader script from linpus -- my SDHC and SD cards are working beautifully in both readers, hotswappable, and I don't want to fiddle. I have everything from the ubuntu 110 page and the comments in the sickboy kernel post.

    I have the same issue with gnome power manager going crazy when I disconnect/reconnect AC. It even dumps a big blank box on the screen for a minute or so after unplugging/replugging.
     
    mattytee, Jan 3, 2009
    #10
  11. SlCKB0Y

    exwannabe

    Joined:
    Dec 30, 2008
    Messages:
    42
    Likes Received:
    0
    I don't have a fix to the gnome_power_applet issue, but it's not that big of a deal. It will go away on it's own in something like 5 minutes.

    The problem is that it screws up your metrics if you are not careful. It does draw some power when it's doing this (watch CPU state %). When I am plugged in (and unplugging to measure drain) I either wait till it's done or kill it off if I am in a hurry. In the real world, it's not a big deal because it will be silent once the "unplug event plus 5 minutes or so" is over and you will not be continually plugging/unplugging.

    What I just found though on another issue is the sound card takes about .4 watts if not powered down. In my kernel (6.28 starting from slicks .config with a few minor changes) the options "Default timeout for HD auto power-save mode" is 0 which disables it. In my rc.local I set it to 10 seconds by "echo 10 > /sys/module/snd_hda_intel/parameters/power_save". Now, that does let it sleep and save about .4W :) , but in my setup it will not automatically unsleep :( . I can manually wake it up (just jacking./unjcaking the headset will do such, and it is enabled for 10 more seconds. This one is worth a resolution. [I believe I have the same ALSA 1.0.18.rc3 as slick has because the final 2.6.28 release had the upgrade, but this might be a userspace issue]

    The wifi driver made no difference to me.

    I am on kubuntu, which may help a little (but also might cause the gnome-power-monitor issue), what are you on matt?.

    I have not made any changes that caused a significant difference outside those already mentioned in the Install Ubuntu guide. It's possible that all the little changes I tried added up to .1 or .2, I will try some comparisons to see if that is the case.

    I am running on an SSD with acerfand keeping the fan from running continually.
     
    exwannabe, Jan 4, 2009
    #11
  12. SlCKB0Y

    mattytee

    Joined:
    Nov 30, 2008
    Messages:
    112
    Likes Received:
    1
    exwannabe, I'm running Gnome with UNR on top. I have noticed that the wifi driver is always the thing causing the most wakeups. Neither "core" runs above 800MHz unless I'm running heavy apps. I think the gnome-power-manager thing is caused by the funky ACPI DSDT that Acer is using, but that's not based on any real knowledge.
     
    mattytee, Jan 5, 2009
    #12
  13. SlCKB0Y

    mattytee

    Joined:
    Nov 30, 2008
    Messages:
    112
    Likes Received:
    1
    I tried my old Linpus install as I hadn't tested it -- usually runs around 8.3 watts at idle. I guess I wasn't doing too badly.

    EDIT: That's without fan control, fan runs pretty much continually, but mine is very quiet for some reason. Typing, and especially clicking, are WAY louder than the little whirr of the fan.
     
    mattytee, Jan 12, 2009
    #13
  14. SlCKB0Y

    Ausweider

    Joined:
    Nov 24, 2008
    Messages:
    35
    Likes Received:
    0
    Running customised kernel disabling all the stuff you dont need seems to help.
    Using powertop's suggestions i get mine down to roughly 9watts with display on, amarok playing mp3s over cifs share.
     
    Ausweider, Jan 12, 2009
    #14
  15. SlCKB0Y

    mattytee

    Joined:
    Nov 30, 2008
    Messages:
    112
    Likes Received:
    1
    Not sure who you were answering here, but

    My original question was if someone could make a full list. For example, the only suggestions powertop made for me were settings for a kernel recompile. It did note that ath5k wifi was responsible for most of my wakeups.

    In my case, I did the following:

    1. installed sickboy's 2.6.28-rc8 (final 2.6.28 broke package management for me).
    2. elevator=noop.
    3. mounted /var/log, /var/cache, /var/log as tmpfs.
    4. put USB sleep commands from linpus in rc.local.
    5. put ondemand for each "core" in rc.local.
    6. killed all unnecessary boot services.
    7. set CONCURRENCY=shell.

    My opinion is, linpus is sleeping wifi and that's where I'm losing the ~.4 watts. I read that madwifi draws less power than ath5k (partially due to better sleeping?) so I'm trying that next.
     
    mattytee, Jan 12, 2009
    #15
  16. SlCKB0Y

    mattytee

    Joined:
    Nov 30, 2008
    Messages:
    112
    Likes Received:
    1
    mattytee, Jan 13, 2009
    #16
  17. SlCKB0Y

    exwannabe

    Joined:
    Dec 30, 2008
    Messages:
    42
    Likes Received:
    0
    Thanks! Short summary:

    In the Gnome Power Manager preferences, Battery Power tab, uncheck "Reduce Baclight...". and "Dim Dispplay..". This stops the App from going insane, which not only reduces functtionality but eats power.

    BTW, matty. Have you checked power with fan off/on?
     
    exwannabe, Jan 14, 2009
    #17
  18. SlCKB0Y

    mattytee

    Joined:
    Nov 30, 2008
    Messages:
    112
    Likes Received:
    1
    I haven't checked with fan off in either distro. My fan runs pretty much constantly, but I'm scared of wearing it out prematurely by letting it run too hot, so no acerfand.

    So, 8.3W at idle in Linpus vs. 8.7W at idle in Ubuntu.

    Anecdotally, it only costs me about 15 minutes of battery life overall, and Ubuntu's worth that to me. I think I'm going to just live with it.
     
    mattytee, Jan 14, 2009
    #18
  19. SlCKB0Y

    exwannabe

    Joined:
    Dec 30, 2008
    Messages:
    42
    Likes Received:
    0
    Your 8.7 seams quite high. Other than looking into the wifi driver all I can think of is:

    . Your sound card is always on, that will cost you a good bit (probably the 15 minute delta).
    . You can save a .1 or .2 by running acerfand. You fears are quite unfunded, the fan is supposed to be normally off an turn on at 50-60C. Acerfand does this (and you can lower the temp settings some if you really want to).

    I do not think Ubuntu should be worse than Limpus. Windows might be doing better with a more advanced graphics driver, that's where a lot of power is. I have been looking in this area, no luck yet.
     
    exwannabe, Jan 15, 2009
    #19
  20. SlCKB0Y

    draft

    Joined:
    Jan 1, 2009
    Messages:
    13
    Likes Received:
    0
    draft, Jan 18, 2009
    #20
Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.