Re: N900 battery life questions, issues, scenarios
 

Any idea why Nokia did not enable it? oversight, slow wakeup response or loss of functionality (what?)

Re: N900 battery life questions, issues, scenarios
 

It appears that there is a SmartReflex patch and also a CPU Frequency Scaling patch available for the Palm Pre, but it's a case of using one or the other, not both.

Nokia have championed CPU Frequency Scaling for some time now in Maemo, perhaps they don't see the need for SmartReflex, or as with the Pre they're not compatible technologies? Although this could just be because the Pre SmartReflex patch locks the CPU at 600Mhz which obviously nullifies the benefits of frequency scaling - no idea why it does that.

It also appears that SmartReflex needs an accurate profile of the silicon in each device, which could be another reason why Nokia have shied away from enabling it by default. SmartReflex appears to be supported by OMAP2 as well as OMAP3, so could potentially be be of some benefit to N8x0 devices as well.

Re: N900 battery life questions, issues, scenarios
 

From what I can see, they do different things. SmartReflex changes the voltage while CPU Frequency Scaling (obviously) changes only the frequency. The power consumption is quadratic in voltage P = V^2/R while linear in frequency, so there is usually more to gain by lowering the voltage. I have no idea about the OMAP processor specifically or whether my argument holds in this specific case.

At any rate, please post here or to the bug if you encounter any instability, but from what I can see, enabling SmartReflex seems to buy a factor of 3-4 on battery life.

Re: N900 battery life questions, issues, scenarios
 

Tried both your methods and its not working.

1. method tells me cannot create nonexistent directory and 2. is permission denied.

I don't have any experiences with this stuff. Help please.

greetz Donsaibot

Re: N900 battery life questions, issues, scenarios
 

You're mistyping the commands, check again and type exactly as above.

You need to be root - install rootsh then run sudo gainroot before entering the above commands.

Re: N900 battery life questions, issues, scenarios
 

Ok what is it supposed do to after i entered
echo 1 > /sys/power/sr_vdd1_autocomp
echo 1 > /sys/power/sr_vdd2_autocomp ?

i copy+paste it now and after that it showed

/home/user #

2.method still shows permission denied with root

Re: N900 battery life questions, issues, scenarios
 

dons it wont tell you that its changed

after you put them temp commands in

type cat /sys/power/sr_vdd1_autocomp

if you havent done the change it will say 0 underneath

if you have succesfully implemented it it will say 1

remeber when you power of or reboot your n900 it will switch back to 0

Re: N900 battery life questions, issues, scenarios
 

Ok it worked.

Thanks :D.

Re: N900 battery life questions, issues, scenarios
 

since this thread is called N900 battery life scenarios, i am going to test a scenario and post the outcome to it right here.

Scenario: Using FM Radio (only 50% of the estimated time) and MSN Haze on 3G. I personally think these 2 apps should be able to be on and give me a good battery time.

(one could call this travelling mode)

My guestimation of how long the battery will last is between 11-13 hours.

Though i hope and i think it should be able to last 24+ hours. which it probably doesnt, which is pretty bad.

No wifi, No GPS, Brightness on 2, no skype/other client on, Bluetooth is on since the radio app requires this. Very little to no websurfing, very little to no calls, very few to no sms, very few to no IM's, just idle on time. Volume on medium full. Only widget: personal dataplan monitor

My phone is charging right now, ill leave it on overnight.

Will post within 24 hours from now.

Re: N900 battery life questions, issues, scenarios
 

Devil,

are you going to enable the special power-saving mode?

FYI. I did a similar test on a completely unmodified phone:
- No 3G, At&t GSM only (does not hunt for 3G), no WIFI at all
- logged in to gtalk, skpe via conversations
- Nokia Messaging check every 30 mins from 8am to midnight
- stock phone, nothing installed at all
- no other apps running

in 24hrs the battery had 28% left.

Contrast to the same test(as similar as I could) on the E71 (Using Fring for gtalk+skype), 59 hours to get to 30% left.