Advanced Linux Process Monitor - htop

Most people familiar with Linux have used the top command line utility to see what process is taking the most CPU or memory. There’s a similar utility called htop that is much easier to use for normal tasks.

htop is an interactive process viewer for Linux. It aims to be a 'better top': you can scroll the process list vertically and horizontally, and select a process to be killed with the arrow keys instead of by typing its process id. It requires ncurses

Comparison between htop and top
    * In 'htop' you can scroll the list vertically and horizontally to see all processes and complete command lines.
    * In 'top' you are subject to a delay for each unassigned key you press (especially annoying when multi-key escape sequences are triggered by accident).
    * 'htop' starts faster ('top' seems to collect data for a while before displaying anything).
    * In 'htop' you don't need to type the process number to kill a process, in 'top' you do.
    * In 'htop' you don't need to type the process number or the priority value to renice a process, in 'top' you do.
    * 'htop' supports mouse operation, 'top' doesn't
    * 'top' is older, hence, more used and tested.

Installation
Ubuntu users can 'upgrade' top to htop by installing htop using the Advanced Package Tool:

    sudo apt-get install htop

OpenSuSe 11.2 users can use "1-click" installer to install htop - here
Once installed, just type htop at a terminal to launch it, and notice the great text-mode graph at the top of the display:

Here is the best part… just use your Up/Down arrow keys to select a process, and then you can kill it with the F9 key if you’d like, or you can change the priority by using the F7 and F8 keys. (note that you’ll have to be root to give anything really high priority).