“htop” is a command-line utility that displays dynamic, real-time information about the running processes on a Linux system. It is considered an enhanced version of the traditional “top” command, providing additional features and improvements for monitoring system resources and managing processes. Here are some key features and aspects of htop:
- Interactive Process Viewer: htop provides an interactive process viewer that displays a list of running processes in a user-friendly interface. Users can navigate through the list of processes using keyboard shortcuts and interact with individual processes to perform various actions.
- Real-Time Monitoring: htop updates the process list and system resource metrics in real-time, allowing users to monitor CPU usage, memory usage, disk activity, and other system metrics as they change over time. This provides instant feedback on the system’s performance and resource utilization.
- Colorful and Customizable Display: htop uses color-coded text and graphical elements to highlight different types of processes and system metrics, making it easier for users to identify critical information at a glance. Users can customize the color scheme and display options to suit their preferences.
- Process Management: htop allows users to manage running processes directly from the interface. Users can send signals to processes, such as terminating or suspending them, adjust process priority and affinity, and view detailed information about individual processes, including their command-line arguments, environment variables, and open files.
- Filtering and Sorting: htop provides options for filtering and sorting the process list based on various criteria, such as CPU usage, memory usage, process name, and user. This allows users to focus on specific subsets of processes and identify performance bottlenecks or resource-intensive tasks more easily.
- Tree View: htop includes a hierarchical process tree view that shows the relationship between parent and child processes. This helps users understand the process hierarchy and identify processes that are spawned by other processes.
- System Information: In addition to process monitoring, htop displays system information such as CPU model, uptime, load average, and memory usage summary at the top of the screen. This provides context for the process activity and helps users assess the overall health of the system.
- Cross-Platform Compatibility: While originally designed for Linux systems, htop has been ported to other Unix-like operating systems such as FreeBSD and macOS, allowing users to monitor processes and system resources on a wide range of platforms.
htop Command Examples
1. Start htop:
# htop
2. Start htop displaying processes owned by a specific user:
# htop --user [username]
3. Sort processes by a specified sort_item (use htop –sort help for available options):
# htop --sort [sort_item]
4. See interactive commands while running htop:
?
5. Switch to a different tab:
tab
6. Display help:
# htop --help
Summary
Overall, htop is a powerful and versatile tool for monitoring system performance and managing processes on Linux and other Unix-like operating systems. Its intuitive interface, real-time updates, customizable display, and comprehensive feature set make it a valuable resource for system administrators, developers, and power users alike.