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Dan Higgins
Dan Higgins

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Day 7 – “TOP Secret Info: Monitoring Your Linux System Like a Pro (Sorta)”

Today, we level up. No more baby steps — we’re stepping into the world of Linux system monitoring.

You’ve created files. You’ve deleted files. You’ve yelled at permission errors. Now it’s time to ask the real questions:

“What the heck is my system even doing right now?”

Welcome to your first taste of Linux surveillance (the good kind). This is where we learn to peek under the hood without accidentally setting anything on fire.

📚 Table of Contents

Meet Your Mission: Know What’s Happening, While It’s Happening

Linux, like a mysterious roommate, is always doing something in the background. Sometimes it’s helpful. Sometimes it’s just eating all your CPU.

Today we meet the tools that let you snoop around — legally and helpfully.

top: The Helicopter Parent of Commands

Type top into your terminal and BAM — instant chaos. It looks like a hacker movie.

You get a live stream of everything your system is doing:
Processes, CPU %s, memory usage, who’s hogging all the RAM snacks.

Need to escape the madness?
Just hit q. (It took me longer than I’d like to admit to figure that out.)

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htop: Like top, But With Swag

If top is your classic Nokia phone, htop is the smartphone with touch gestures.
It’s colorful. It’s interactive. You can scroll and sort. It even shows pretty bars. (Yes, I got too excited.)

If it’s not installed yet, run:

sudo dnf install htop

And then:

htop

Now go ahead — watch your system like a Linux MI6 agent.

free -h: The Memory Therapist

Ever feel like your system “feels” slow? free -h tells you why.

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The -h means “human readable,” so you don’t have to decode how many gigabytes are in 1283768K.

It shows how much RAM is being used, what’s free, and whether your poor swap space is crying.

df -h: The Disk Detective

Is your system mysteriously out of space? Are you hoarding logs and files like a digital raccoon?

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This command shows you where all your disk space is going. The -h gives you sane, human-readable output instead of some cursed byte math.

Your Mini Mission

  1. Run top or htop and find what’s eating the most CPU.
  2. Use free -h to check if you’re low on memory.
  3. Run df -h to spot disk usage issues.

Pro tip: Open a few tabs in Firefox or VS Code and watch how the CPU and RAM change in real time. It’s like watching a live documentary about your own system.

Why This Matters

You don’t need to be a Linux wizard (yet), but being able to monitor your system is one of those skills that separates you from the pack.

It’s how you spot performance issues, debug slowdowns, and — most importantly — pretend to look busy on Zoom calls.

Real talk: This stuff will come up in cloud jobs, interviews, and real-world troubleshooting.

So practice now, while it’s still kind of fun and no one’s yelling at you.

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