$ su root -c "snice -12 -c X"

This will give your X11 server a serious priority boost and make the mouse and painting behavior much snappier.

This command was tested on Red Hat 6.2. Your mileage may vary. The snice command is an intelligent renice. If you don't have snice, you can do this:

  $ su root 
  $ ps -ef | grep X | more

Figure out the process id of your X process. On my machine it looks like this:

  100 S root     29158 29157  0  60   0    - 19675 do_sel Apr06 ?        03:37:27 X :0 -auth /home/joi/.Xauthority

The pid is the second number, in this example it's 29158. Now renice it:

  $ renice -12 29158

  29158: old priority 0, new priority -12

You have to be logged in as root to do this because only root can give a process a negative priority number. (The smaller the number, the higher the priority the process has.)
2001-May-03 11:19am gyles19@visi.com