Bug 364979

Summary:	kpowersave miscalculates consumption
Product:	[openSUSE] openSUSE 10.3	Reporter:	Juergen Weigert <jw>
Component:	Mobile Devices	Assignee:	Danny Al-Gaaf <dalgaaf>
Status:	RESOLVED FIXED	QA Contact:	E-mail List <qa-bugs>
Severity:	Minor
Priority:	P5 - None	CC:	behlert, coolo, hmuelle
Version:	Final
Target Milestone:	---
Hardware:	x86
OS:	openSUSE 10.3
Whiteboard:	marked-ForNext10.3YOU
Found By:	---	Services Priority:
Business Priority:		Blocker:	---
Marketing QA Status:	---	IT Deployment:	---
Bug Depends on:
Bug Blocks:	357354

Description Juergen Weigert 2008-02-26 21:03:53 UTC

kpowersave shows in the middle pane the battery state, the precense of AC power and the current consumption. The consumption is spelled out in 5 digits precision, so one could assume the measurement is fairly accurate.

Running on battery, the idle consumption is between 15105 mW and 17268 mW depending on display Brightness. This appears to be plausible.

Connecting the AC while a 14.4V 5.2aH Battery is connected and ca 80% charged makes the power consumption rise to ca 40 Watts. This appears to be plausible.

Connecting the AC while the regular (14.4V 2.5Ah) battery is connected a ca. 95% full, makes the power consumption drop immediatly to 10784 mW. It gradually 
sinks down to 2732 mW when only a few minutes remain until the battery is fully charged. The Power consumption is no longer displayed, when the battery is full.

The readings from the last test are obviously false, as the laptop definitly generates more heat than 2.732 Watts could ever cause. 

I assume, with this type of battery connected, only the charging consumption of the battery is printed, not the consumtion of the machine. With the other type of battery the sum of both is printed.

Comment 1 Stefan Behlert 2008-02-26 22:55:14 UTC

Jürgen, can you check what 
/proc/acpi/battery/BAT0/state
says in the 2732 Watt case?

Comment 2 Christian Zoz 2008-02-28 18:44:31 UTC

With 2732 Watt is says: 'selfdestruction in 5 seconds' :)

> With the other type of battery the sum of both is printed.

Which leads to the assumption that it depends on the hardware what you get.

Afaik, kps just takes the numbers it get's from ACPI. And ACPI has just a function to ask the battery. So it's up to the battery what you read.

And this data comes from /proc/acpi/__battery__: Therefore this is just battery data and not the consumption of the system.

All we could change in this kind is the way this data is presented to the user to avoid misunderstanding.

Jürgen, if you like you may check that information with the preinstalled Windoze.

Comment 3 Juergen Weigert 2008-02-28 19:50:49 UTC

(I never had a windows preinstalled on the machine and I would rather close
 this defect as worksforme than installing one now.)

Yes, the 'Power Consumption' field is in sync with "/proc/acpi/battery/BAT0/state/present rate:" 
Changing display brightness, swithcing on/off wlan+bluetooth has no effect on the reading while charging. It gives/takes between 1 and 2 Watts while discharging.
I have the same effect with both batteries when they are nearly full. 
My eralier test was invalid, because only one of them was nearly full.

Please make it clear what the power consumption field is indicating.
If I understand you correctly, it either indicates the machines consumption 
or the battery's consumption. But never the total consumption through the AC cable.

Simply saying 'Power Consumption', made me believe it is the total.

I'd suggest to change it to 'Battery Power Consumption' and 
make a reference to this bugzilla in the po file.

Please also remove one or two decimal places.

Comment 4 Danny Al-Gaaf 2008-02-28 22:57:42 UTC

This was already fixed for 10.3 (2007-11-02), but the package isn't released yet since there are some open issues with one bug. You can try the KPowersave package from my openSUSE buildservice project (http://download.opensuse.org/repositories/home:/dkukawka/openSUSE_10.3/). The power consumtion is now only shown if the battery is discharging.

Comment 9 Harald Mueller-Ney 2008-04-16 19:11:27 UTC

openSUSE 11.0 will reach Betaphase soon, we have a fixed package in openSUSE build service:
http://download.opensuse.org/repositories/home:/dkukawka/openSUSE_10.3/

Issue is not critical, we will not provide an patch update. Make sure issue is fixed for 11.0/factory - afterwards we could close this bug.

Comment 10 Danny Al-Gaaf 2008-04-17 16:09:24 UTC

Project Management and Maintainance team decided those bugs (#333744, #349083, #364979) are not worth fixing with an online update, so i have to close them now. Sorry for that.