Memory

Swap

Empty swap

sudo swapoff -a && sudo swapon -a

Modify swapiness or how often the swap should be used.

# Check
cat /proc/sys/vm/swappiness
# Set new value
sudo sysctl vm.swappiness=10
# Set new persistent value in /etc/sysctl.conf
vm.swappiness = 10

Memory usage

List 10 processes that use the most memory

ps aux --sort=-%mem | awk 'NR<=10{print $0}'