Install wmmemload by entering the following commands in the terminal:
sudo apt update sudo apt install wmmemload
Description:
WindowMaker dockapp to monitor memory and swap usage
wmmemload displays the current memory and swap usage as a percentage value. It is based on wmcpuload and wmmemmon, and as such looks very nice alongside those. . wmmemload is designed to work with the WindowMaker dock, but will work with other window managers as well.
Homepage: http://windowmaker.org/dockapps/?name=wmmemload
Version: 0.1.8-2build1
Section: universe/x11