Linux CLI Monitoring Tools: htop, atop, nmon, vtop, bashtop, gtop, glances

htop

htop is an interactive process viewer for Linux that improves on the classic top command with color themes, mouse support, horizontal and vertical scrolling, and a tree view of processes.

Installation: sudo apt install htop Interactive commands (use arrow keys, PgUp/PgDn, etc.):

Space – mark/unmark a process (operations apply to all marked processes, e.g., kill)
U – unmark all processes
s – trace a process with strace
l – show files opened by a process (requires lsof)
I – reverse sort order
+ / - – expand/collapse sub‑trees in tree view
a – set CPU affinity for a process
u – show processes of a specific user
M – sort by memory usage
P – sort by CPU usage
T – sort by time+
F – follow a process as it moves in the list
K – toggle kernel threads visibility
H – toggle user threads visibility
Ctrl‑L – refresh
Numbers – jump to a PID

atop

atop records system and process activity at regular intervals, logging CPU, memory, disk, and network usage to a file for later analysis.

Installation:

sudo apt install atop

nmon

nmon (Nigel's performance Monitor) captures comprehensive resource statistics on AIX and Linux, outputting data to files that can be visualized with the nmon_analyzer tool.

Installation: sudo apt install nmon Key interactive keys:

# c – CPU information
# m – memory information
# d – disk information
# n – network information
# t – process information
# h – help
# q – quit

vtop

vtop is a Node.js‑based, open‑source terminal monitor that visualizes CPU and memory usage of multi‑process applications such as NGINX, Apache, or Chrome.

Installation:

sudo apt install nodejs
sudo apt install npm
sudo npm install -g vtop

Useful options and shortcuts:

# vtop --theme wizard – change color theme
# vtop --update-interval 20 – set refresh interval to 20 ms
# vtop --quit-after 5 – exit after 5 seconds
# vtop -h – display help

bashtop

bashtop is a Bash‑based Linux resource monitor that shows CPU, memory, disk, network, and process statistics with a game‑inspired UI.

Features include easy navigation, process filtering, sorting, signal sending, auto‑scaling network graphs, and update notifications.

Dependencies:

Bash 4.4+

Git

GNU coreutils

GNU sed, awk, grep, ps

lm‑sensors (optional for CPU temperature)

Installation:

git clone https://github.com/aristocratos/bashtop.git
cd bashtop
sudo make install

Uninstall:

sudo make uninstall

gtop

gtop provides a terminal dashboard for monitoring processes, CPU, and memory usage.

Installation:

sudo apt install nodejs
sudo apt install npm
sudo npm install -g gtop

glances

glances is an open‑source, cross‑platform monitoring tool written in Python that displays CPU, load, memory, disk I/O, network traffic, file system, and temperature information.

Installation:

sudo apt install glances