htop – An interactive process viewer that can dynamically observe the status of system processes

htop is a command-line utility that displays the current state of the system processes in real-time. It provides an interactive interface that allows users to monitor the performance of their system and identify resource-intensive processes that may be causing performance issues.


The htop command is a powerful tool that provides a detailed overview of the system processes running on a Linux system. It displays the processes in a hierarchical tree structure, making it easy to identify the parent-child relationships between processes. It also provides real-time information about the CPU usage, memory usage, and other system resources that are being consumed by each process.

To use htop, simply type htop into the terminal and press enter. The htop interface will appear, displaying a list of the currently running processes. By default, the processes are sorted by their CPU usage, with the most resource-intensive processes listed at the top.

The htop interface provides several key features that make it a valuable tool for system administrators and users. These include:

  • Interactive process management: Users can easily select and manage individual processes using the arrow keys and function keys. For example, users can send signals to processes, adjust process priority, and even kill processes directly from the htop interface.
  • Customizable display: Users can customize the htop display to show or hide specific columns, change the sort order of processes, and adjust the refresh rate of the display.
  • Detailed process information: Users can view detailed information about each process, including its process ID, user, CPU usage, memory usage, and more.


The htop command supports several options that can be used to customize its behavior. These options are listed in the table below:

Option Description
-d delay Specifies the delay between screen updates in tenths of a second.
-u user Displays only processes owned by the specified user.
-p pid Displays only the process with the specified PID.
-C Turns off color output.
-h Displays a help message and exits.

Troubleshooting tips

If you encounter issues when using the htop command, there are a few troubleshooting tips that you can try:

  • Ensure that you have the htop command installed on your system. If it is not installed, you can install it using your Linux distribution’s package manager.
  • Check that you are running the htop command with the correct permissions. Some system processes may require root privileges to display.
  • If you are experiencing performance issues with your system, use htop to identify resource-intensive processes that may be causing the problem. You can then use the kill command to terminate these processes.


  • htop is a powerful tool that should be used with caution. Users should be careful when terminating processes, as doing so can cause system instability or data loss.
  • The htop command is not available on all Linux distributions by default. Users may need to install it manually using their distribution’s package manager.