How to check the usage of swap in Linux?

The following command can be used to check the swap usage in a Linux system:

1. cost-free

free -h

1. enable paging and swapping in the operating system

swapon -s

1. vmstat is a command used in Unix and Linux operating systems to display virtual memory statistics.

vmstat -s

1. best
2. htop is a software application.

top

Or

htop

The above command allows you to check the usage of swap in a Linux system, in order to monitor the memory resources of the system in a timely manner.