Master Linux Process Monitoring: From top to htop to btop

Overview

Linux/Unix administrators often need to monitor per‑process CPU usage, memory consumption, and related metrics. The built‑in top utility provides a basic dynamic view, htop adds a colored, scrollable UI with keyboard navigation, and btop (also known as btop++) is a modern C++‑based replacement with richer visual features.

top

top

is a standard, always‑available tool that displays processes and allows sorting by CPU or memory without any installation.

htop

htop

improves on top by using colors, supporting horizontal scrolling, and enabling arrow‑key selection of processes. Users can send signals such as SIGKILL directly from the interface. It offers configurable views but requires separate installation.

btop

btop

is a modern, C++‑based system monitor that runs on Linux, macOS, BSD and other Unix‑like systems. Installation examples: brew install btop or clone the repository and follow the documentation at https://github.com/aristocratos/btop.

UI modules and presets

btop defines four core modules—CPU, Storage, Network, and Processes. Four preset layouts (0‑3) combine these modules. Press p to cycle presets, or use the numeric shortcuts 1 ‑ 4 to toggle individual modules on or off.

CPU module

Displays CPU model, per‑core usage, temperature, overall load, and a real‑time graph.

Storage module

Shows both memory usage and disk usage in a concise visual format.

Network module

Presents aggregate upload and download traffic; press b or n to switch between network interfaces.

Process module

Columns include:

pid

Program (process name)

Command (executable path)

Threads

User

MemB (memory usage)

Cpu% (CPU percentage)

Key bindings: e – toggle tree view r – sort column (toggle ascending/descending) f – filter by string k – kill selected process

Configuration and themes

The default configuration resides in $HOME/.config/btop, where preset layouts and module visibility can be edited. Themes are stored in ~/.config/btop/themes. Additional themes can be downloaded from https://github.com/aristocratos/btop/tree/main/themes. Inside btop, press m → OPTIONS → Color theme to switch themes using the arrow keys.

Summary

btop provides a visually appealing, feature‑rich, and keyboard‑driven interface for real‑time system monitoring, making it a practical alternative to both top and htop.