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- - N900 battery life questions, issues, scenarios (https://talk.maemo.org/showthread.php?t=31020)

Re: N900 battery issue

good to know :) good luck

Re: N900 battery life

About the keyboard backlight:

Quote:

Originally Posted by GeneralAntilles (Post 397355)

It's controlled automatically by the ambient light sensor.

Is it possible to control the sensitivity? On the N810, the keyboard backlight is switched on even when not really useful.

Re: N900 battery life

i still cant complain. i streamdd music for two ours straight yesterday, and took two calls during that time while also browsing the web....pretty heavy use. battery was over half full after everything.

Re: N900 battery life

Quote:

Originally Posted by qole (Post 397344)

Just a few notes from personal experience.

If you mess at all with the WiFi power settings, your battery life will really, really suck.

Also, beware desktop widgets that display info that gets updated regularly. I was warned at the Summit by people in the know that the Facebook widget isn't very power-optimised.

If you need better battery life, turn off e-mail checking, too. I've heard reports from hard-core users that it can really help your battery life.

Taking a lot of photos really seems to hammer the battery.

Best thing to have is that "load-applet" mentioned above and watch the left indicator. If it stays at four squares, with the top one flashing red, for any length of time, your battery is headed for a premature demise.

I notice that occasionally (seems it might be related to XChat? Not sure), some mysterious process called hildon-xinput-sounds hammers my CPU and I have to kill it or suffer a quick battery death.

uh. howto on the xchat pls. :p

Re: N900 battery life

Quote:

Originally Posted by qole (Post 397358)

Yes, if you want to keep the backlight off during the day, don't be left-handed. :(

put into simpler terms... the phone shuts off the backlight if it detects that it is light out via the prox sensor, so dont cover it with your hand. youll know youre messing the sensor up when the screen randomly dims on you while using the device.

Re: N900 battery life

XChat is in the Extras-devel repository... What specifically do you want in the way of a how-to?

Re: N900 battery life

disabled facebook widget... made a massive difference in usage.
went from 8am - 10pm. Played music for 1 hour, maintained 3G connection with Nokia Messaging, Yahoo and MSN constantly connected.
Used about 1hr total of responding to IMs/reading emails and showing video playback off.

Not sure how the facebook app made such a huge difference. Had to half-charge it midday last time I was at work with it on. Plus its not what i want anyway, I want just the notifications not a feed. Would rather bring up the full website in this lovely browser.

Re: N900 battery issue

Quote:

Originally Posted by marauder (Post 400650)

My N900 seems to be working fine now, since I recharged yesterady evening. I still have an almost full battery right now after 12 hours.

I tried using the "top" command in xterm window again, this time sorting the processes with the P and M keys (as jaysire suggested, thanks!), but found nothing abnormal, all processes under 5%.

When I had the battery problem yesterday, I had no active data connection, no browser windows open. The device was inidle connection.

I'm wondering if there could be some kind of issue with the N900 wifi receiver being turned on even if the status icon doen't say so? (Could have something to do with the fact that occasionally I disconnect from my wifi router, and if I want to reconnect, the N900 won't see the router until I reboot it). Or maybe sometimes when charging the N900 reports the battery is fully charged but it's not...I really don't know. I will have to wait for it to happen again and investigate further. If it won't happen again so much better.

All I know is that now everything looks good, the battery seems to be performing very well. Yesterday I was shocked to see it get empty in 4.5 hours on and idle device...

Yes , i experienced exactly the same issue with the wifi refusing to reconnect
until reboot and this was in the day with worst battery life (about 4 hrs).
There must be some bug in the wifi driver or wpa_supplicant....

I've also changed some settings in rcS with values that improved battery life in my G1:

Code:

# User settings to reduce battery drain

# Was 100

echo 40 > /proc/sys/vm/swappiness



# Experimental settings

# Was 5

echo 1 > /proc/sys/vm/page-cluster

# default: 0 Helps keep SSD from getting worn

echo 5 > /proc/sys/vm/laptop_mode

# Was 500

echo 5000 > /proc/sys/vm/dirty_expire_centisecs

# default: 500

echo 800 > /proc/sys/vm/dirty_writeback_centisecs

# default: 5

echo 10 > /proc/sys/vm/dirty_background_ratio

# default: 10

echo 16 > /proc/sys/vm/dirty_ratio



#Over Clock CPU when in use, puts at lower freq when idle

# available frequencies 600000 550000 500000 250000

echo 550000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq

echo 600000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq



# default: 0

echo 200 > /sys/devices/system/cpu/cpu0/cpufreq/ondemand/powersave_bias



# Was 300000

echo 2000000 > /sys/devices/system/cpu/cpu0/cpufreq/ondemand/sampling_rate



# Was 95, percent cpu usage before going up a speed step

echo 45 > /sys/devices/system/cpu/cpu0/cpufreq/ondemand/up_threshold



# Set "No-op" scheduler for mtdblocks and mmc

for i in /sys/block/mmcblk0 /sys/block/mmcblk1 `ls -1 /sys/block/mtdblock*`

do

        echo "noop" > $i/queue/scheduler

done

and there seems to be some improvement in battery life, but it still needs
more testing. I will report in the next days if there are some improvements.

Update:
so far after 15 hrs still 90% battery with normal use pattern: a few calls
a little wifi, some sms.

Re: N900 battery issue

Quote:

Originally Posted by marauder (Post 400650)

Ok this has happen to me today, Unplugged at 4pm, dead at 11pm. No data connections.. nothing open......... just idleing.

Re: N900 battery issue

This morning my N900 had the same problem again. It could not find my home WiFi connection. I would suspect it has something to do with battery draining.

Is there something that can be done through xterm when N900 fails to find an existing WiFi signal, without having to reboot? Is there a wifi related service I could try to restart to get this working or some way to check wifi module status?

I'll try to find out how to reproduce this wifi issue...

Quote:

When I had the battery problem yesterday, I had no active data connection, no browser windows open. The device was inidle connection.

I messed up here. I meant "in idle condition". No data connection.