Complete Guide! How to Instal htop on Linux

A Complete Guide about htop Command

Imagine your Linux system suddenly becomes sluggish and you notice that the applications are running slower than usual.There could be various reasons for this slowdown. Is it a runaway process consuming all CPU resources? Is there a memory leak causing the system to swap excessively? Or maybe disk I/O is bottlenecking the performance? These are common issues that can cripple a system’s performance and lead to downtime if not addressed promptly.

This is where the Linux htop command comes to the rescue. In this guide, we’ll cover the usage of the htop command in detail, along with its various options and features. You’ll learn how to monitor system resources effectively, manage processes interactively, and customize the htop interface to suit your needs. By the end of this guide, you’ll be equipped with the knowledge to tackle performance issues swiftly and keep your Linux systems running smoothly.

What is the htop Command?

The htop command is an interactive process viewer for Unix-based systems, including Linux. It serves as an upgraded and user-friendly alternative to the traditional top command, offering a more intuitive and visually appealing interface. With htop, you can easily monitor and manage system processes, CPU and memory usage, and other vital system resources.

Installing htop on Linux

When you try to execute the htop command on the terminal directly, you may encounter an error. This error occurs because the htop command is not installed on your Linux distribution:

To resolve this, you need to install htop using the package manager specific to your Linux distribution:

In this article, we will install htop on Ubuntu, which is a Debian-based Linux distribution. To do this, we will execute the command:

Once the installation is complete, we can verify that htop is correctly installed by executing the command:

This command displays the version of htop installed on our system, confirming that the installation was successful.

The Basic Usage of the htop Command

When you run the htop command without any options, it displays a detailed and interactive view of your system’s current state:

Output Overview

The htop command output is divided into several sections, each providing valuable information about your system. The main sections are:

• CPU Usage: Displays the current CPU usage, including the percentage of CPU used by each core.
• Memory and Swap: Shows the current memory and swap usage, including the total amount of memory and swap space available.
• Processes: Lists all running processes, including their process ID (PID), parent process ID (PPID), CPU usage, memory usage, and status.
• Threads: Displays the number of threads running on the system.
• Load Average: Shows the system’s load average, which represents the average number of processes waiting for CPU time.
• Uptime: Displays the system’s uptime, which is the time elapsed since the last boot.

Basic htop Command Options

The htop command offers several options and parameters that allow you to customize its behavior and output. In this section, we will explore the basic htop command options, including -h, -v, and -d, and provide examples of how to use them.

-h Option: Display Help

The -h option displays the htop command’s help message and exits the program. When you run htop -h, the command prints a brief usage guide to the terminal, including a list of available options and parameters:

-d Option: Set Display Delay

The -d option sets the delay between updates in seconds. By default, htop updates its display every 2 seconds. You can adjust this delay using the -d option:

Here we used 50 which updates the display after every 5 seconds.

-F Option: Display Fields

The -F option allows you to customize the fields displayed in the htop output. You can specify a comma-separated list of field names to include or exclude:

p Option: Specify PIDs

The -p option allows you to specify a list of process IDs (PIDs) to monitor. You can provide a single PID or a comma-separated list of PIDs:

This command displays only the processes with the specified PIDs (1234, 5678, and 9012) in the htop output.

-t Option: Tree View

The -t option enables the tree view in htop, which displays processes in a hierarchical structure:

This command displays the htop output in a tree view, showing the parent-child relationships between processes.

These additional options provide more flexibility and customization possibilities for the htop command. By combining these options, you can create a tailored monitoring experience that suits your specific needs.

Advanced htop Usage Tips

Sorting Processes

To sort processes by memory usage in htop, press F6, then select MEM% from the list. This allows you to quickly identify memory-hungry processes.

Killing Processes

To kill a process in htop, navigate to the process using the arrow keys, press F9, select the signal to send (usually SIGKILL), and press Enter.

Using Filters

You can filter processes by pressing F4 and entering the search term. This is useful for narrowing down specific processes quickly.

Customizing Display

Press F2 to enter the setup menu where you can customize various aspects of the htop interface, including column selection, color scheme, and meter settings.

Key Features of the htop Command

• Real-time Process Monitoring: Continuously updated list of processes, displaying critical metrics such as CPU and memory usage.
• Interactive and User-Friendly Interface: Intuitive navigation and process management with keyboard shortcuts.
• Customizable Display: Flexibility to show or hide columns, adjust color schemes, and tailor the layout to personal preferences.
• Sortable and Searchable Process List: Easily sort processes by various criteria and quickly locate specific processes with the search function.
• Advanced Filtering Options: Apply filters to narrow down the list of processes for more focused monitoring.
• Process Management: Send signals to processes for actions like termination, pausing, or resuming.

Conclusion

The htop command is a powerful tool for Linux system administrators, offering a user-friendly and interactive way to monitor system resources, manage processes, and troubleshoot performance issues. With its customizable display, sortable and searchable process list, and real-time system resource monitoring, htop provides a comprehensive overview of system performance.

Moreover, by mastering the various options and features of htop, including the -h, -d, -F, -p, and -t options, you can customize your monitoring experience to suit your specific needs and quickly identify and resolve performance bottlenecks. With htop, you can ensure your Linux systems run smoothly and efficiently.