Ubuntu 20+ Add swap space

Create a swap file

sudo fallocate -l 2G /swapfile

sudo chmod 600 /swapfile

sudo mkswap /swapfile

Output

Setting up swapspace version 1, size = 2 GiB (2147479552 bytes)

no label, UUID=fde7d2c8-06ea-400a-9027-fd731d8ab4c8

sudo swapon /swapfile

vim nano /etc/fstab

Add this line

/swapfile swap swap defaults 0 0

sudo swapon --show

Output

NAME      TYPE      SIZE  USED PRIO

/swapfile file        2G    0B   -1

sudo free -h

Output

             total        used        free      shared  buff/cache   available

Mem:          981Mi        97Mi        68Mi       0.0Ki       814Mi       735Mi

Swap:         2.0Gi        10Mi       1.9Gi

More details https://linuxize.com/post/how-to-add-swap-space-on-ubuntu-20-04/