Cpu usage by X

[Marko Vojinovic]

On Tuesday 04 May 2010 17:23:25 DB wrote:
> Sometimes when I start my desktop, System Monitor tells me that "X" is
> running at max CPU %-age.  Other times, "X" is 4th or 5th in the list (I
> selected the CPU column to put the highest users on top), using 1 or 2 %.
> 
> So, my question to you all:  What is "X" doing & how can I stop it doing
> whatever & keep my CPU chip cool?????  BTW, I have no idea what X is!!!
> I've tried killing it & that usually kills my desktop; just now killing
> it caused the system to restart.

man Xserver says:

<quote>
NAME
       Xserver - X Window System display server

SYNOPSIS
       X [option ...]

DESCRIPTION
       X is the generic name for the X Window System display server.  It is 
frequently a link or a copy of the appropriate server binary for driving the 
most frequently used server on a given machine.
</quote>

In other words, simply put, X is the program that produces picture on your 
monitor. KDE uses X to draw windows, mouse pointer (the "arrow") is drawn on 
the screen by X, and so on. X is the thing that sits between the graphics card 
driver and everything else on the system that wants to draw things on your 
screen. Killing X is a synonym to killing your "desktop". The only situation 
when X is not used is when you boot into runlevel 3 (terminal consoles, white-
text-on-black-background experience).

If X is spiking the CPU, the problem is probably due to your video card 
drivers, or KDE desktop effects or Compiz or a movie or game being played or 
some other graphics-intensive activity. If you describe what you are doing on 
the system when it spikes, it might help narrow down the problem. Otherwise, 
it's impossible to tell.

HTH, :-)
Marko