QUOTE(Star_knight79 @ Jul 7 2011, 08:20 PM)
Hi, May I know how do we check background services that are running?
How to terminate them? Will the phone reopen the apps/ services again?
What are the essential background services that MUST BE RUNNING all the time?
Thanks for the advice.

I don't like to install and use system (cpu/memory/network) monitoring tools because the monitoring itself can sometimes affect the phone's performance. Therefore I just go to Settings / Applications / Running services to see what is going on under the hood.
In fact, I don't even kill running apps. I sometimes press the back button to come out of an app, or I press the home button, leaving the OS to manage itself by using AutoKiller to set minfree settings at boot (Moderate preset).
Note : In CM7, we can also enable 'long-press back button' to kill the actively running app. Good to have for emergency use since there is no actual Task Manager or Program Monitor like what Samsung-based ROMs have.
Currently on my phone, I see these apps/services listed as running:
Media - 4MB (1 process and 0 services)
Settings - 14MB (1 process and 0 services)
Voodoo Control Plus - 6.4MB (1 process and 1 service)
WhatsApp - 5.6MB (1 process and 1 service)
Maps - 5.7MB (1 process and 1 service)
Skype - 5.5MB (1 process and 1 service)
Bluetooth Share - 3.1MB (1 process and 2 services)
Google Services - 14MB (2 processes and 2 services)
Smart Keyboard Pro - 8.2MB (1 process and 1 service)
135MB RAM Used, 166MB RAM free
So far my phone has been fine, apps launch quickly, I can multitask with no delay and battery life seems OK for me especially after the recent CM7 nightly updates.
This post has been edited by kmrdeva: Jul 7 2011, 08:44 PM