Swap space in any operating system is amount of disk space reserve for moving inactive pages from RAM. Swap space are of two type dedicate swap or of swap files in linux OS. Here we will create a swap file for the linux system.
We assume that the system does have not swap partition for this guide.
Open the terminal, and enter the following command to check.
free h //or df -h
If you have sufficient space in you hard-disk then lets continue.
Here let us increase to 2GB (assuming existing one has 1GB space as given in the article)
dd if=/dev/zero of=/var/swapfile bs=1024k count=2000
chmod 0600 /var/swapfile
echo '/var/swapfile none swap sw 0 0' | tee -a /etc/fstab