Swappiness in Ubuntu 15.04

You can often get a performance boost from your Ubuntu system by swapping out physical memory to disk (swap partition) less.

Ubuntu seems to have a default “Swappiness” level of 60.

Try dropping this to 20 or even 10

sudo -s
vi /etc/sysctl.conf

Add to the very bottom of this file:

vm.swappiness=20
:wq
reboot

After reboot
cat /proc/sys/vm/swappiness to make sure the new value took effect.

There is an official page that covers this all in excruciating detail but the above is the gist of of it.