Since a couple of years ago, Linux distributions use a swap file (to exchange with Ram memory when it is exhausted or to hibernate the system) instead of a swap partition. If, like I do, instead of clean installing version upgrading is used, it is possible that the system still uses the swap partition. In may case I use Ubuntu and both for the desktop and the laptop computers the first installation was done more than 3 years ago, and afterwards I upgraded the system several times. In this article it is shown how to convert a Swap partition to a a Swap file.
We first disable the swap:
sudo swapoff -a
Next, we create the swap file. The recommended size can be found in the table shown in this link:
The following command will create the swapfile:
sudo fallocate -l 3G /swapfile
This creates a swap file of 3Gb, which has to be adjusted for each system. This creates the file in the root of the system (/) but it can be changed if not enough space is available at this partition.
Next, we restrict the file permisions:
sudo chmod 600 /swapfile
Only "root" will be able to write and read this file. We now dedicate this file to swap:
sudo mkswap /swapfile
Last, we have to assure that the swap file is mounted each time the system starts: