My N900 has never had the most stellar battery performance. With heavy use I normally had to recharge half way through the day. With light use I would need a recharge by about 7pm. I am normally logged on to skype, hotmail, ymail, googletalk and facebook chat so that could be why the battery dies so easily.

However, in the last week or so something has gone terribly wrong with my battery. It is doing four hours only. This is even with me having switched off all chats and switching to 2G mode. The battery just drains constantly and consistently to last no more than four hours.

So obviously there is a serious problem somewhere as the drain has nothing to do with how heavily I use it and even with heavy use four hours seems really really terrible. Either the battery has developed a fault or peharps there is a heavy process going on in the background that is eating the battery. I haven't noticed any slow down though.

The only recent things I have installed are Desktop command execution widget, midnight commander, proximityd, tweakr, htop.

Htop shows as top process:
messageb (User) CPU 26%.

Next is: user CPU 20%;
then 2 root showing about 12%.

Total CPU is 85-87.8%. Surely this is very very high right and could explain the terrible battery?

Did you take the firmware update in the last week or so?

>95% CPU should be idle if you are running no apps. Did you try restarting? What is the CPU usage after a fresh boot?

I was having exactly same problem for the last week or two until yesterday (except my unexplained high CPU usage was massively affecting performance). I couldn't figure it out and was ready to reflash it until I decided to try running the 1.1.1 update it has shown available for the last couple of days (I'm in the UK) in case this helped. Suprisingly this seems to have sorted the problem completely and myh CPU usage is down and my battery life back up. Obviously this doesn't help root out the cause of the problem but as long as it doesn't go back to the way it was I'm not too fussed.

I rebooted and Htop is still showing 86.9% usage despite not running any applications.

Did not do a recent firmware update. Although I am in the UK I bought my N900 in the US and updated ages ago when the rest of the world got the update.

One thing I just thought to try is a hard reset. Will see if that helps. If not I guess I would have to reflash the device.

Edit: Wow CPU just went up to 100% for a second.

That CPU usage is suspicious. Could you post top or htop output? Perhaps we could track down what process/application is making the trouble...

just a thought incase some of you have missunderstood "top" (task manager in xterminal.

install conky and see what the cpu usage is or install system info widget (shows cpu and memeory)

Probably some extras-devel apps, check top and post the output.
Only one I remember so far was syncevolution frontend cpu nomnom, but it was fixed already.

as i am writting this reply, the keyboard is out. 2 widgets are running, 2.5G connected, 2 apps and web pages are open.

currently in idle, my cpu usage is 2% and 170mb of ram usage.

as i take action (like switching between apps and web windows) the cpu usage goes up to 21% and 175mb ram.

i have no more than 5 apps installed from devel and testing.

i am also running skype, msn, yahoo and facebook im's.

when i receive an email or im, the cpu goes up by 32%, ram is up to 175mb.

almost all of my devices used half of their ram even in idle mode.
just wanna ask if that is normal.

if i run my device at this rate continuosly, mt battery will last for 18-20 hrs.

Guys!!

I'm facing a similar problem... My battery barely lasts through the day and I need to recharge it by 5 pm. I have no desktop widgets running at the moment and I don't use the phone on wi-fi at all. It only runs on Edge cellular data connection and I use it for some browsing (mainly this forum). The call duration is also not very high - probably half an hour in all. Add to that some texting and 30 minutes of music.. and that should sum it all.

I observed it using the Battery Eye application today and saw that the battery continuously keeps dying even if I'm not using the phone actively.

I'm using the PR 1.1.1. The only reason I could think of is that I have tried out a lot of apps from testing and devel, but have uninstalled them now. I'm not sure if something hasn't been removed and is still eating the battery.

Can someone help please!!!