What Is the Htop Follow Process Feature?

The htop utility is an interactive system monitor for Linux that provides a real-time, color-coded view of system resources and running processes. While navigating a busy system, processes constantly shift positions on the screen as their CPU or memory usage changes, making manual tracking difficult. The “Follow Process” feature solves this problem by locking the interface’s focus onto a single chosen process, automatically scrolling and moving the selection bar to track that specific item regardless of how its resource consumption fluctuates.

Why the Process List Constantly Shifts

By default, htop sorts processes based on their CPU usage. Because resource consumption is highly dynamic, a process using 15% CPU might be at the top of the list one second, and drop down several rows the next second when another process spikes.

If you are trying to monitor a specific application, this constant shuffling can cause you to lose sight of it, or worse, accidentally send a termination signal (like SIGKILL) to the wrong process because the list jumped just as you pressed the key.

How the “Follow Process” Feature Solves This

When you trigger the Follow Process feature, you tell htop to anchor your selection highlight to that specific Process ID (PID).

• Automatic Tracking: As the process moves up and down the list based on the active sorting criteria, the highlight bar moves with it.
• Smart Scrolling: If the process moves entirely off the visible screen because its resource usage dropped, htop will automatically scroll the window up or down to keep that process in plain view.
• Safer Management: Keeping the process safely highlighted ensures that any subsequent actions you take—such as changing its priority (renicing) or killing it—are executed on the correct target.

How to Use Follow Process in htop

Using this feature requires only a couple of keystrokes while htop is running in your terminal:

1. Use the Up and Down arrow keys to navigate the list and highlight the process you want to track.
2. Press the F key (uppercase F, or Shift + f).
3. A visual indicator (usually a change in the selection bar or an explicit tag depending on your configuration) will confirm that htop is now following that specific PID.
4. To stop tracking the process and return to normal scrolling, simply press F again or move your cursor manually to a different process.