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Z61m: much higher power consumption using Linux
Posted: Fri Nov 24, 2006 10:21 am
by theclaw
Hi there,
when using Windows on my Z61m, my minimum power consumption when on battery is about 13W, but on linux the *minimum* power consumption is about ~25W - with disabled wifi, minimized display brightness, and the cpus throttled to 1GHz each.
It also seems that I don't have the C4 processor-powerstate, doing "/proc/acpi/processor/CPU0/power" only lists states C1 to C3. The CPU used is a coreduo T2500, the distribution debian with kernel 2.6.18.2. The same problem occurs with several linux livecds, namely Knoppix and Ubuntu 6.06 und 6.10
any suggestions?
thanks in advance
PS: I'm using the latest BIOS, v1.13
greets,
johannes
Posted: Fri Nov 24, 2006 12:12 pm
by syntelman
The linux kernel doesn't handle CoreDuo's well with frequency scaling/power management etc. Something is fishy but there's people working on it. Word is that 2.6.19 might help, if not I'm sure better support will be included in the next release. In other words we'll just have to wait.
Posted: Fri Nov 24, 2006 12:57 pm
by theclaw
syntelman wrote:The linux kernel doesn't handle CoreDuo's well with frequency scaling/power management etc. Something is fishy but there's people working on it. Word is that 2.6.19 might help, if not I'm sure better support will be included in the next release. In other words we'll just have to wait.
thanks for that information, that helps me to ensure that the hardware doesn't cause the problems. Could you please give me some references where you got that information? I'd be interested in the progress
thanks!
greets,
johannes
Posted: Thu Nov 30, 2006 12:02 am
by magnus
How do you see the current wattage being used by the system? If it's an easy thing to do, software wise, it'd be a neat way to find out if my system is as bad as yours (windows vs linux).
Posted: Thu Nov 30, 2006 12:58 pm
by theclaw
magnus wrote:How do you see the current wattage being used by the system? If it's an easy thing to do, software wise, it'd be a neat way to find out if my system is as bad as yours (windows vs linux).
Hi there, thanks for the help. Yes, its really a easy to find out the current power consumption, simply look in /proc/acpi/battery/BAT0/state - if the /proc/acpi/battery directory doesn't exist you have to load the "battery" kernel module, but quite certainly the directory exists in most linux distributions.
It would also be *really* nice if you gave me the contents of /proc/acpi/processor/CPU0/power (to see if the C4 power state exists on your Z61m, because here it doesn't

.). The kernel version and distribution in use is also likely to be helpfull
many thanks in advance!
johannes
Posted: Thu Nov 30, 2006 3:48 pm
by magnus
Ok...
First things first. It seems I forgot to mention that I'm on a Z61t, not a Z61m, but it shouldn't be that big a difference I guess.
As for power usage, right now it's at 17 W with me downloading the kernel from the git-repos at ubuntu, and browsing with WLan.
I looked at the /proc/acpi/processor/CPU0/power, and there's no C4 there, only C1 thorugh C3
Code: Select all
GNU nano 1.3.12 File: /proc/acpi/processor/CPU0/power
active state: C3
max_cstate: C8
bus master activity: 00000000
states:
C1: type[C1] promotion[C2] demotion[--] latency[000] usage[00000010] duration[00000000000000000000]
C2: type[C2] promotion[C3] demotion[C1] latency[001] usage[10573568] duration[00000000000907786596]
*C3: type[C3] promotion[--] demotion[C2] latency[057] usage[44812320] duration[00000000006091729383]
One thing is that when I had more than one powersaving daemon running, they ruined it for eachother, so that none of them worked.
Good luck, and tell me if there's any more I can help with.
-Magnus
Posted: Thu Nov 30, 2006 5:06 pm
by theclaw
thanks, seems I'm not the only one who doesn't have the C4 Powerstate. Hmm.. - I think my problem only occurs when certain modules are loaded - at least with no modules loaded I also have about 17W wattage. I hope newer kernels will fix this problem..
greets,
johannes
Posted: Thu Nov 30, 2006 6:02 pm
by dfumento
If you use the standard Lenovo SLED Linux with the downloaded Thinkvantage utilities you can get the great power usage. I did on my X60s.
See:
http://forum.thinkpads.com/viewtopic.php?t=31975
Posted: Fri Dec 01, 2006 11:24 am
by theclaw
hmm, but I don't want to use SLED - debian/ubuntu is my distribution of choice. I wonder if those tools also work with other distributions, but unfortunately I can't test - the download link in the article doesn't work (some license hadn't been found or something like that, error 550)
thanks anyhow
greets,
johannes
Posted: Fri Dec 01, 2006 6:03 pm
by magnus
I wasn't able to get Thinkvantage to work on my Kubuntu. But I didn't spend too much time on it, as there's some great alternatives out there anyway.
-M