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LAB-MON-01 - Real-time Monitoring (top/htop)

Use top and htop to inspect CPU and memory usage, sort active processes, and stop a disposable practice load.

MON Monitoring & Logging Vault

Real-time Monitoring (top/htop)

Use top and htop to inspect CPU and memory usage, sort active processes, and stop a disposable practice load.

20 min BEGINNER LINUX
Before this lab
Lab LAB-PROC-01 - The Process Lifecycle
What success looks like
  • Use top and htop to inspect CPU and memory usage, sort active processes, and stop a disposable practice load.
  • Repeat the workflow without copy-paste or step-by-step prompting.
Safety notes
  • Monitoring and diagnostic commands are usually safe, but avoid running destructive follow-up commands outside the lab target.

Part A: The Field Guide

What This Lab Is Really About

This lab teaches you how to look at a live system without guessing.

You will practice:

  • opening a live process monitor
  • reading CPU and memory columns
  • re-sorting the view
  • stopping a disposable high-CPU process you created yourself

That last part matters because the goal is controlled practice, not random process killing.

Command Reference

Monitoring tools

top htop

Useful habits:

  • in top, press Shift + M to sort by memory
  • in htop, use function keys or column selection to sort the list
  • quit with q

Part B: The Drill Deck

Terminal required: use a normal Linux terminal and create only disposable load.

G
Guided Step by step - type exactly this and compare the result
>

Exercise G1: Read top

  1. Launch top.
  2. Find the load average numbers.
  3. Look at the PID, %CPU, and %MEM columns.
  4. Press Shift + M to sort by memory usage.
  5. Press q to quit.

Exercise G2: Try htop if Available

  1. If htop is already installed, run it.
  2. Sort by CPU and then by memory.
  3. Notice the difference between the summary bars and the process list.
  4. Quit with q.

Exercise G3: Understand What You Are Looking At

  1. Compare the top few rows in top or htop.
  2. Ask:
    • which process is using the most CPU right now?
    • which is using the most memory?
    • are those the same process or different ones?
S
Solo Task described, hints available - figure it out
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Exercise S1: Create a Disposable CPU Load

  1. Open a second terminal.
  2. Run this safe disposable loop:
yes > /dev/null
  1. Switch back to the first terminal and open top or htop.
  2. Confirm that the yes process rises toward the top of the CPU list.

Exercise S2: Stop the Practice Load

  1. Identify the PID or highlight the process in htop.
  2. Stop it using either the monitor interface or a separate terminal with kill.
  3. Confirm that CPU usage drops afterward.
M
Mission Real scenario - no hints, combine multiple skills
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Mission M1: Explain the Evidence

Create one short written explanation for yourself:

  1. which process used the most CPU during the lab
  2. how you verified that it was the practice process
  3. what changed in the monitor after you stopped it

If you can answer those three points clearly, you are learning monitoring rather than just memorizing keystrokes.

What to do next

Best next step Learning

Return to the related lesson if you want the concept explained more deeply.

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Troubleshooting

Use problem-first help when this lab maps to a real issue.

Open now Reference

Look up commands, topics, and tasks while you practice.

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