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[admdvs]

what really (will) make this a killer laptop will be the power management capabilites.  from what i've heard, some will be included in the first update and the rest will mostly arrive in the coming months.  i've heard the hardware already supports them - its just the software that needs to be updated.

but if don't use their software, we won't get the power management updates.. i assume the are not in the firmware, but in fedora and/or sugar?
does anyone know for certain?

i know when the default installation offers 10 hours of normal usage and 24 hours in e-book mode.. stepping back to xunbuto with only 3 hours of battery life will be a difficult thing to swallow.   

i assume eventually the power management code will be ported over to the most popular alternative OS's for this little green machine...? but it might be a long time for that to surface....?

[MikeToronto]

"i know when the default installation offers 10 hours of normal usage..."

I'm a bit skeptical of this claim. What is "normal usage" exactly? I use my XO to surf the web about 95% of the time. WiFi is a battery eater. So what they consider "normal" usage is probably spending 9 hours using Write and 1 hour surfing the web.

[admdvs]

to-mike

the wifi only uses about 1 watt.  i have a power usage reader and  i just plugged in my XO and removed the battery.. it was using 6 watts with the radio off and7 watts with it on.  i do get 3 hours of usage on my XO with no power management.. i can only assume that the cpu uses a lot and well see the biggests gains with that.. also  i think i remember reading somewhere that the wifi will have power management..? 
i want to believe in the 10 hour claim..

*btw.. i'm at yonge/bathurst.
 

[MikeToronto]

I'm at King West. There are at least 3 people in this building who also placed OLPC orders. They aren't showing up in the Neighbourhood yet, so either they haven't got them yet or the walls are made of lead in this condo. I thought that mesh networking was supposed to work at ranges up to a KM or something...

[MikeToronto]

*btw.. i'm at yonge/bathurst.

Yonge and Bathurst don't intersect do they? Is there a Toronto Meet-Up planned?

[sracer]

Supposing that the 10 hour figure is correct under Sugar, what good is the extra 7 hours if it will take me 10 hours to do under Sugar that would take me 3 under XUbuntu?   

[Carol]

I I thought that mesh networking was supposed to work at ranges up to a KM or something...

Range of the Mesh Network
What is the range between 2 laptops using just the mesh network
In excellent conditions, over 1.3 km. (along a rural road, held up high)

http://wiki.laptop.org/go/Ask_OLPC_a_Question/New

I got .914 km. over farmland.  Here's my post bragging about my XOs.   This was the only trial I ran and they transmitted with no difficulty so I'd bet it could be increased.   Indoors?  I'm not aware of any tests on that.  Sounds like you're in a great position to do some testing.  Keep us posted - a lot of people are curious about finding other XOs in their neighborhood.

http://olpcnews.com/forum/index.php?topic=810.0

[cmonkey]

Well, the CPU has a TDP of 3.1 watts, and AMD claims normal usage is 1.3 watts.  There must be significant amounts of power being used elsewhere then.

I dont have a power meter, but can you check how much power the backlight uses?

Also, it makes sense that people are getting a km in open air with no interference.  With walls and noise in the 2.4ghz band, the range is much smaller.

[Heng]

but if don't use their software, we won't get the power management updates.. i assume the are not in the firmware, but in fedora and/or sugar?
does anyone know for certain?

No, I don't know for certain. But from experience with power management on Linux, I'ld say, most power management features are in the kernel and you should have no trouble using them with a different brand of Linux.

i know when the default installation offers 10 hours of normal usage and 24 hours in e-book mode.. stepping back to xunbuto with only 3 hours of battery life will be a difficult thing to swallow.

There are lies, damn lies, and laptop manufacturer's statements about battery life. While I hope, that the XO with proper power management software, will beat every other laptop, I still doubt 10 hours.

[admdvs]

(off topic)
sorry.. i ment bathurst / finch (west of yonge).. I'm not really interested in a TO meetup. won't get anything out of it that you can't get from this website.

(on topic) I did some digging..

interesting finds:
- http://wiki.laptop.org/go/Power_Management_Tips "how to shut down the DCON (Display CONtroller, which uses a lot of power).. 
turn off:  echo "1" > /sys/devices/platform/dcon/sleep
and to wake back up: echo "0" > /sys/devices/platform/dcon/sleep

- http://wiki.laptop.org/go/Power_Management "The DCON chip lets us take over refresh of our very low power flat panel and therefore completely power off the processor board. Given our flat panel is usable in gray scale mode at .1 watt, you can see that the leakage currents and power supply power consumption of the system board can dominate power consumption easily.
We are also able to leave the Marvell wireless module to operate independently, forwarding packets in the mesh while possibly everything else is powered down. "

-http://wiki.laptop.org/go/OHM_power_management: full list of what they plan to do

- http://dev.laptop.org/query?status=new&status=assigned&status=reopened&keywords=%7Epower&order=priority  (full list of power related tickets)

- http://wiki.laptop.org/go/Table_of_Power_Mgmt details what sections of the laptop are powered in different states


I can't find it again, but i remember reading that we will only get the option to suspend / hibernate in update 1 and update 2 will contain the true power savings where the CPU will shut down the computer is idle for more than a second or two then spring to live in a few milliseconds -- THIS is where the true power savings will happen, and this is (i think) something that no other notebooks are doing, so i am still hopeful for a 10 hour batter and 25 hour ebook mode.

 

[cmonkey]

Most modern processors support various CPU C states to save power. http://en.wikipedia.org/wiki/Advanced_Configuration_and_Power_Interface#Processor_states

What's unique about the OLPC is that the processor can remain in a sleep state while work is done without it by the wifi chipset or the DCON.

10 or 25 hours still seems unrealistic to me on the current hardware.  However, for certain tasks, like working as a mesh node while not in use, or ebook mode, there are no doubt huge gains left to be made in battery life.

[sola]

I only hope it will be possible to power down the mesh network completely without hurting the AP connection. I assume that eats a lot too and there is no need for the mesh in a lot of situations.

[pgf]

I only hope it will be possible to power down the mesh network completely without hurting the AP connection. I assume that eats a lot too and there is no need for the mesh in a lot of situations.

the "mesh network" and the "AP connection" are just two operating modes of the same hardware.  they're both wireless.  so you can't power off one without losing the other.  there may be ways of telling the system to stop scanning for other mesh peers, and that might conserve power, but i'm not sure about that.

paul