Heres a dirty trick i usually use on all my servers i administrate to keep swap from being used.

type in
Code: 
vi /etc/sysctl.conf
add to the file sysctl.conf at the very bottom unless the vm.swappiness is defined then edit it
Code: 
vm.swappiness = 1
USUALLY you want to restart for it to use the new settings, but you can run this command
Code: 
/sbin/sysctl -p
That should update the system settings. The just to make sure try to restart mysql and such that uses swap.

Also make sure you are not using all your ram or else that could also be why swap is being used.