How to clear swap in Linux

By Luis Freitas

• cli
• command

There have been times where it has been necessary for me to clear out the swap space on a Linux system. In order to do this, you must first make sure that you have enough free memory to hold what is being used by swap.
I usually do this in a few steps. You do need to be root to do this. First I want to see what is currently being used.

free

Then I run the actual commands that empty the swap:

swapoff -a && swapon -a

Then I check what is being used after doing this.

free

or

top