How to Pause screen updates in htop?

The htop utility is a popular interactive process viewer for Linux that provides real-time updates on system resources like CPU, memory, and running processes. However, because the screen refreshes constantly, tracking a rapidly shifting process or reading a specific line of data can be challenging. This article explains how to temporarily freeze the screen updates in htop, allowing you to analyze system metrics at your own pace without the data shifting beneath your cursor.

Freezing the Display with the Pause Key

The most direct way to halt the real-time updates in htop is by using the Pause key on your keyboard.

• To pause updates: Press the Pause key (sometimes labeled as Break on certain keyboards). As soon as you press it, htop stops refreshing the resource bars and process list.
• To resume updates: Press the Pause key a second time, and the utility will immediately resume its live, real-time monitoring.

Alternative Method: Opening a Menu

If your keyboard lacks a dedicated Pause key—which is common on modern laptops—you can achieve a temporary freeze by opening one of htop’s interactive menus.

• Trigger a menu: Press F2 (Setup), F3 (Search), or F4 (Filter).
• Why it works: While these prompt menus or configuration screens are active, htop suspends background process list refreshes. This allows you to safely look at the static data currently visible on your screen.
• To resume updates: Press Esc to exit the menu and return to the active, refreshing process view.

Adjusting the Refresh Interval

If you find yourself needing to pause htop frequently because the data changes too fast, you might prefer to simply slow down the update frequency permanently.

You can change the delay interval by launching htop from your terminal with the -d flag followed by a value in tenths of a second. For example, to set the screen to refresh only once every 5 seconds, use the following command:

htop -d 50