Since the three aforementioned system monitoring tools can hold their own quite easily, I’ll focus on two alternatives which I believe can also hold their own as replacements or at least compliment top and htop. They are, Glances and nnom.
yum install -y htop
Glances – system monitor
Glances is open-source software to monitor and collect operating system statistics. Glances aims to present the max amount of information, in the minimum amount of space. Glances is a good htop alternative as it can adapt dynamically when displaying system information, depending on the terminal size. Remote monitoring can be done via terminal, Web interface or API (XMLRPC and RESTful). Glances is written in Python and uses the psutil library to get information from your system. Stats can also be exported to external time/value databases.
curl -L https://bit.ly/glances | /bin/bash