What are the unnecessary services/daemons and how to stop them?
 

my dear fellow N900ers,

i'm about to embark on a long trail walk (30+ hours) in a couple of weeks and i'd like to record it with either eCoach or GPS Recorder on my N900. as many of you might have guessed already, my only concern is power consumption. i have two batteries (the Nokia BL-5J) at my disposal. and i will re-flash my device and install only those two apps, or only one of them, if i could find out which one of eCoach and GPS Recorder is better than the other. basically, i'll be using my N900 as a GPS device only. i'm using another phone for calls.

i've already taken all necessary means to save power (e.g. setting the brightness to lowest, turning off time update, using a black background on my desktop without any shortcut or widget). and i know i can "tracker-processes -t" to stop trackerd. is there anything else i can stop?

i think i will also explore QCPUFreq to limit the maximum CPU frequency and/or to use SmartReflex. does anyone have any experience on this (e.g. lowest sustainable maximum frequency)?

Re: What are the unnecessary services/daemons and how to stop them?
 

[movie voice] How do I stop these... DEMONS?! [/movie voice]

My N900 will run fine for 30 hours on a single charge, with light web browsing and phone calls. I think you're fine.

For the GPS, the N900 wants to have an internet connection. So you're not going to be able to disable the cellular modem. But this means that your Internet-connecting apps will be waking up and doing data transfers, e.g., modest, apt-get, etc.

You can also kill browserd.

Re: What are the unnecessary services/daemons and how to stop them?
 

how do i stop browserd? i just did a "killall browser browserd" in root (found from another thread) and it rebooted the N900.

the internet connection is only required when establishing a GPS fix. after that, i can switch the N900 to offline mode, providing the satellite signals are strong enough. i've tried it.

i've also found a way to "disable" auto updates check:
gconftool -s --type int /apps/hildon/update-notifier/check_interval A_REALLY_LARGE_NUMBER

Re: What are the unnecessary services/daemons and how to stop them?
 

Yesterday, I had my N900 in offline mode for six hours, plus about one hour of very light wifi (letting it sync, etc). In total, the battery lost about 8% (from 90% to 82%).

The N900 uses almost no power when in offline mode, locked. Two batteries will be just fine if you come out of offline mode to get a GPS fix every ~30 minutes.

Re: What are the unnecessary services/daemons and how to stop them?
 

Once the GPS has a fix, there is no reason not to shut down the cellular modem.

Re: What are the unnecessary services/daemons and how to stop them?
 

afaik there is no need at all to use the "a-gps" feature. It just speeds up getting the first fix.
If you got 5 minutes of time before you start recording it should work without cellular modem switched on.

just my 5ct

Jonni

Re: What are the unnecessary services/daemons and how to stop them?
 

why not using it and after you have fix, switch to offline mode?

running gps chip for 5 minutes takes probably more current than sending and receiving some bytes with cellular modem.

e: one more tip or two: do not lid up the display unless you really really have to. switch off blinking led.

Re: What are the unnecessary services/daemons and how to stop them?
 

had a trial this weekend. using eCoach with 20 sec interval, switched to offline mode after getting GPS fix, battery went from 96% to 59% after 8 hours. so one battery should be able to last me 20 hours. will try GPS Recorder next weekend.

Re: What are the unnecessary services/daemons and how to stop them?
 

If you have a couple of weeks before you go, buy a Mugen battery, they are bulky, but last forever. I have just got one and the only critisium I have is the camera slider, it works but the design is poor!

As the screen is back lit a black background will make no difference to battery life, instead set some photos relating to you trip to help inspire you :)

Re: What are the unnecessary services/daemons and how to stop them?
 

search forums for 'Optimize_N900'

its a little script that does wonders. i put it on my desktop as a beecon widget and it never fails to remedy slowdowns