battery life

hi, i have 3-cell battery
laptop works on battery for 2:40h on windows but only for 1:50-2:00h on fedora
there must be a way to increase battery life, but i'm a beginner with linux so i don't know.

thnx to everyone for help

 

have you measured this time? as i get about 2hrs actual use on both linux and windows

phil

 

yes ... its approximatly correct, so i guess there's a need to tweak fedora...
or is there some other distro that can be installed from usb and uses less battery?

 

is this what windows tells you when you have a full battery? as it doesn't last near as long as that in actual use like i said i get about 2 hrs from both fedora10 xfce and windows xp during normal use , even linpus only get's just over two hours and it was specifically modified for the one

phil

 

but i tested it... both windows and linux
i measured time and as i said the time written in OS is approx correct

maybe i'll give linpus a shot if i find a way to install it from usb

 

which version of the aspire one do you have?

for installing linpus from usb see here>>> http://macles.blogspot.com/2008/12/acer ... y-dvd.html

phil

 

Read my thread at the ubuntu forum. I did some measurements. From those, I estimated that with my current ubuntu setup, I could browse slashdot.org in one tab for 2 hours and 40 minutes on a 3 cell (sound muted, lowest brightness, wifi on).

These are the biggest things that help from my testing:
- Reduce brightness (function key plus left or right)
- Disable wifi (there's a switch on the machine, but it might not
be active by default in fedora)
- Have your USB ports use less power when idle
- Keep your applications light/disable startup services not needed
- Use CPU scaling and put it to something energy conserving

Things I have not tested:
- Disable swap. I suspect this could make a worthwhile difference. But I always run without swap so haven't really tested anything.
- I always use ext2 or ext4 with noatime and they work well. How other filesystems/options affect battery life, I don't really know.
- Mute sound (I have the impression this helps a small bit but I haven't done any conclusive testing yet... perhaps not worth mentioning but it's an easy thing to do).

There are a bunch of other tweaks being mentioned in aspire one guides. I use some of them but even combined, they make a minor difference at best (or so I think anyway, from my limited testing). The things above are the big ones. If you get good at them, you'll have an energy efficient system.

I don't doubt a fairly light windows xp install is better than typical linux distributions when it comes to battery life. That's been my impression for quite some time. But as I've seen myself, you can good battery life out of linux as well but it can require a bit of tweaking. My aspire one can sit idle with x and a window manager running for 3.5 hours on a 3 cell battery...

 

what is your configuration? Exact details.

Like others I only get around 2hrs on linux.

 

I've already told you how. I could be more specific but as I wrote, I don't even use fedora.

I do a core/base install of debian or ubuntu running on ext2 or ext4 with noatime and no swap. Then add whatever I need. Only lightweight window managers (IceWM rocks). Try to avoid KDE and Gnome applications, try to use GTK+ or QT applications that do not tie in to KDE or Gnome. Use command line substitutes if it's applications you don't need to use very often (like Ceni as network manager).

Have cpufrequtils installed and set it to conservative or ondemand.

Search for ubuntu aspire one guide, debian aspire one guide and fedora aspire one guide. You'll get lots of powersaving tips there. Add those to a startup script (like rc.local, if fedora even uses that).

Add elevator=noop to your grub.cfg (at least that's the file in grub2).

Remove every service you don't need. I use sysv-rc-conf but that's maybe a debian tool. You could always do it manually or use the appropriate fedora tool. I remove 10-15 services from ubuntu!

If you haven't figured it out, I'm one of those minimalistic types who don't like to use heavy apps. I bought the 512 mb edition even if I could easily have bought the 1 gb one, because I knew I could easily fit in everything in 512 mb ram without swap space . However, if you're trying to fit in a typical KDE 4 desktop set onto this sort of machine, and trying to optimize it for battery life... well... good luck! I just don't think it will work out very well.

As for Windows XP, I've never really done any battery testing on it but I've heard many reports that it gets better battery life on various laptops. That's to be expected, as every laptop's battery life is optimized towards Windows XP.

The included Linpus did a good job with battery life, but it was optimized for the aspire one. Generally, many laptops are not tested towards linux compatibility, and they're certainly not optimized for battery life on linux systems. Therefore, there's no denying that linux users are treated as second class citizens by hardware makers and battery life is one of those things where you suffer a bit. You can make things better there, but that depends on your "operating system lifestyle".

 

A few Fedora-specific comments:
1. instead of grub.cfg look for /boot/grub/grub.conf
2. Fedora does, indeed use /etc/rc.local
3. From the main menu System->Administration->Services provides a GUI that will allow you to enable or disable selected services