The Linux Kernel Power Issues Continues To Bite Users

[jannis]

About your power-measurement thingy:
As I noted in the other thread (not sure wether you read it), here's how I would do it:

With ThinkPads and the "tp_smapi" kernel module you can discharge the battery even with AC connected by writing a "1" to "/sys/devices/platform/smapi/BAT0/force_discharge" (switching back to AC can be done by writing a 0 or automatically when the battery is empty). So your laptop won't power off when you got the AC adapter inserted and the discharging forced.
When the AC is connected but the discharging forced, you can read the system power usage from "cat /proc/acpi/battery/BAT0/state | grep rate".

This way you could at least automate the "charge/build new kernel/wait until battery has reached >50%/reboot - switch to battery - measure - switch to AC" cycle with accurate (and easy!) measuring.

More info (with hardware compatibility matrix) is here: http://www.thinkwiki.org/wiki/Tp_smapi

I remember you mentioning a T60 at some time so I think it would work for you.

[speculatrix]

I work for a company which does energy monitoring, and it is possible to interrogate the power meter using a simple API. I have asked if there's scope for loaning or donation a unit to you. I can't promise anything will come about, but I feel it's the least I can do as I enjoy reading phoronix.

best wishes
Paul

[Lederhosen]

not sure what the availability is for these in your area, but cyberpower makes some rather nice UPS units that can feed usage back to the pc via serial or USB cable.

I picked up a 1500 watt unit for about $140, their FAQ lists linux support as well as some utilities.

http://www.cyberpowersystems.com/sup...atibility.html

Might make it possible for you to automate the usage testing..

[crumja]

clearly you have no idea about how Linux kernel development works and should stop talking as if you do.

Dave

Well, I think I am entitled to hold an opinion about how development works based on comments from devs, including Ted Tso and Con Kolivas. Essentially, devs run such exotic configurations that they don't even think about common end-user usage scenarios such as a hard reset, power usage, or scheduler issues.

Oh, btw Dave, how's it like to get slammed by Linus every merge cycle about drm related crap?

If you don't want the development community to have this stigma, why not convince them to take up some of these issues? If the report earlier is correct, why has no kernel dev even mentioned this issue in the mailing list? Are they too far removed from review sites such as Phoronix and Tomshardware (both of which pointed out this power issue)? Do they think it's all hype and unsubstantiable by "hard numbers"?

[thofke]

Did you even check it out? It has an USB connector, I only meant with RS-232 that you should probably interface with it via telnet or something. My guess is that it has a RS-232 to USB adapter integrated. Better than some proprietary protocol just for Windows, right?

Hey, Michael, I'm glad that I was able to convince you in looking at this device (the WattsUp Pro), and I'm glad that you looked even further than me and found linux support on some forum! Thanks for taking my suggestion serious and for all the work you are doing right now for mobile linux users!