top and htop (live monitoring) in Linux CLI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the command to start the basic system monitor tool.

Linux CLI

[1]

Drag options to blanks, or click blank then click option'

Atop

Bps

Chtop

Dvmstat

Attempts:

3 left

💡 Hint

Common Mistakes

Typing 'htop' instead of 'top' when htop is not installed.

The top command starts the basic live system monitor showing processes and resource usage.

2fill in blank

medium

Complete the command to start the enhanced system monitor with a user-friendly interface.

Linux CLI

[1]

Drag options to blanks, or click blank then click option'

Ahtop

Btop

Ciotop

Dglances

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'top' when 'htop' is requested.

The htop command starts an enhanced interactive system monitor with color and easier navigation.

3fill in blank

hard

Fix the error in the command to quit the top or htop program.

Linux CLI

Press [1] to exit the program.

Drag options to blanks, or click blank then click option'

ACtrl+C

BEsc

Cq

DCtrl+Z

Attempts:

3 left

💡 Hint

Common Mistakes

Trying Ctrl+C which sends interrupt but may not exit cleanly.

Pressing q cleanly exits both top and htop.

4fill in blank

hard

Fill both blanks to filter processes by user and sort by CPU usage in top.

Linux CLI

top -u [1] -o [2]

Drag options to blanks, or click blank then click option'

Ausername

Bpid

Ccpu

Dmem

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'pid' or 'mem' for sorting when CPU is requested.

The -u option filters by user name, and -o cpu sorts by CPU usage.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps process IDs to their memory usage if memory usage is above 100MB.

Linux CLI

{pid: mem for pid, mem in processes.items() if mem [1] [2]

Drag options to blanks, or click blank then click option'

A>

B100

CMB

Dand

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'and' in place of comparison operator.

The comprehension filters processes where memory usage is greater than 100MB.

Practice

1. What is the main purpose of the top command in Linux?

easy

A. To display live system and process information

B. To edit text files

C. To compile programs

D. To manage user accounts

Solution

1. Step 1: Understand the function of top

   The top command shows real-time information about system processes and resource usage.

2. Step 2: Compare with other options

   Options B, C, and D relate to different commands or tools, not top.

3. Final Answer:

   To display live system and process information -> Option A

4. Quick Check:

   top = live system info [OK]

Hint: Remember: top shows live system stats [OK]

Common Mistakes:

• Confusing top with text editors like nano
• Thinking top manages users
• Assuming top compiles code

2. Which of the following commands correctly starts htop in the terminal?

easy

A. start htop

B. htop -start

C. htop &

D. run htop

Solution

1. Step 1: Identify correct syntax to run htop

   The command htop runs the program; adding & runs it in background.

2. Step 2: Check other options for correctness

   Options B, C, and D are not valid Linux commands to start htop.

3. Final Answer:

   htop & -> Option C

4. Quick Check:

   Run htop with 'htop &' [OK]

Hint: Run htop by typing 'htop' or 'htop &' [OK]

Common Mistakes:

• Using invalid flags like -start
• Typing 'start htop' which is Windows style
• Using 'run htop' which is not a Linux command

3. You run top and see a process using 95% CPU. What does this indicate?

medium

A. The process is waiting for user input

B. The process is sleeping and not active

C. The process is stopped

D. The process is using most of the CPU power

Solution

1. Step 1: Interpret CPU usage in top

   High CPU percentage means the process is actively using CPU resources.

2. Step 2: Understand other states

   Sleeping or waiting processes use little CPU; stopped processes do not use CPU.

3. Final Answer:

   The process is using most of the CPU power -> Option D

4. Quick Check:

   High CPU% = active process [OK]

Hint: High CPU% means active process using CPU [OK]

Common Mistakes:

• Thinking high CPU means sleeping
• Confusing waiting with stopped
• Assuming stopped processes use CPU

4. You try to run htop but get: command not found. What should you do?

medium

A. Restart the computer

B. Install htop using the package manager

C. Run top instead

D. Check if you typed htop correctly

Solution

1. Step 1: Understand 'command not found' error

   This means htop is not installed or not in PATH.

2. Step 2: Fix by installing htop

   Use package manager like sudo apt install htop or sudo yum install htop to install.

3. Final Answer:

   Install htop using the package manager -> Option B

4. Quick Check:

   command not found = install missing tool [OK]

Hint: Install missing commands with package manager [OK]

Common Mistakes:

• Restarting without installing
• Ignoring the error and running top
• Not checking spelling before install

5. You want to find and kill the process using the most memory using htop. What steps should you follow?

hard

A. Sort by memory, select process, press F9 to kill

B. Sort by CPU, select process, press F10 to kill

C. Sort by PID, select process, press F3 to kill

D. Sort by user, select process, press F5 to kill

Solution

1. Step 1: Sort processes by memory usage in htop

   Press F6 or click the memory column to sort descending by memory.

2. Step 2: Select the top memory-consuming process and kill it

   Use arrow keys to select process, then press F9 to kill it.

3. Final Answer:

   Sort by memory, select process, press F9 to kill -> Option A

4. Quick Check:

   htop kill = sort mem + F9 [OK]

Hint: In htop, F9 kills selected process after sorting [OK]

Common Mistakes:

• Using wrong function keys to kill
• Sorting by CPU instead of memory
• Trying to kill by PID without selecting