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Re: Optimizing power drain

Posted: 24 Nov 2009, 20:19
by voria
TeutonJon78 wrote: Touchpad
It seems like this might not get fixed. There are some related bugs that after looking into it, seem to be similar and probably are. No one seems to believe that it's a problem though. Quite frankly, if only a touchpad is generating that many interrupts and not a mouse of other things, then it seems to me that there is a problem with the driver.
Looking at the upstream bug report (link) it seems to be an hardware constraint, so there is nothing we can do to fix the problem. :(

Re: Optimizing power drain

Posted: 24 Nov 2009, 20:44
by TeutonJon78
I got that from the upstream report as well. But there is no actual mention of what restraint it is. It does seem odd that other trackpoints increase only slightly or not at all, but the synaptics one needs 450+ interrupts per second to send data. That sounds less like a hardware constraint and more like a flaw somewhere.

I used to work in software development, and "it's a hardware constraint" is also often used when the problem isn't really understood or the person doesn't understand the code/missed the bug (or it might actually be a hardware constraint).

I have to say it's not a hardware constraint though. When I sit in Windows with WLAN on and using the mouse, BatteryBar reports my usage at 7.9W. I can only get that low in Ubuntu if I turn every thing off and don't touch the computer. If windows can do it, Ubuntu should be able to do it.

Re: Optimizing power drain

Posted: 02 Dec 2009, 21:59
by mtah
Hi, first time poster here. I'm curious to know what power drain powertop is reporting for you all (along with machine, distro, kernel and additional tweaks you are using). Thanks!

Re: Optimizing power drain

Posted: 03 Dec 2009, 09:38
by marshmn
mtah wrote:I'm curious to know what power drain powertop is reporting for you all (along with machine, distro, kernel and additional tweaks you are using). Thanks!
I've not played with powertop before, but I've just had a look - quite addictive to try different things and see what the change is :)

I found that if I have my N140 sitting in an idle state, with firefox running in the background, wireless usb mouse plugged in but not being touched, then the power consumption reported by powertop was ~ 6.4W. If I start moving the mouse around though then it jumps up to ~ 9.7W.

This is on an N140 running Karmic, kernel 2.6.31 and with no real power-saving tweaks just yet.

Matt

Re: Optimizing power drain

Posted: 04 Dec 2009, 09:54
by voria
Here powertop reports 8.2W (long term 6.3W) on NC10, ubuntu karmic, screen brightness at 30%, bluetooth disabled and laptop-mode enabled.