Adjust Your swappiness!

By | 2010/06/23

What is swappiness and why the heck should I change it?

swappiness is a value between 1 and 100 which controls the priority of your system using ram vs. swap.

Making this change will greatly increase the performance of your box! Especially if you have a recent system with lots of ram.

A swappiness value of 1 means avoid swap as much as possible and only use ram.

A swappiness value of 100 means avoid ram as much as possible and only use swap.

By default, Ubuntu is set for swappiness of 60.

For desktop users I recommend changing swappiness to a value of 10.

For most servers I suggest setting it to a value of 25.

If you have 4, 8, or more GB of ram, consider setting your swappiness to 1.


Ok, so how to I check my swappiness?

Do this command to check your current swappiness value:

cat /proc/sys/vm/swappiness

You can temporarily change it by issuing:

sudo sysctl vm.swappiness=10

To set the value permanently on your box, edit this file:

sudo nano /etc/sysctl.conf

And put in the value you desire, such as:

vm.swappiness=10