like the title says im trying to run gnome-do;s docky but it lags so much to the point on not being able to use. i have googled this problem and i keep finding the way to fix it is to add
edit /etc/X11/xorg.conf and under the "Device" section add:
Option "MigrationHeuristic" "greedy"

But im running karmic koala and it doesnt have a x11/xorg.conf file ,, someone els told me to just make one and add it there, so i did but that made it so i couldnt login to my computer , so please if anyone knows what i can do to make this run better please let me know. feel free to email me at THANKS IN ADVANCE