A Guide for Monitoring CPU Usage and Processes in Linux

When you are using Linux, knowing how to check your system’s CPU and process usage is a very useful skill. It helps you diagnose performance issues, find processes hogging resources, and keep everything running smoothly. In this blog, we will go through the process of Monitoring CPU Usage and Processes in Linux.

Why Monitor CPU and Processes?

A system under heavy load because of too many processes, a misbehaving program, or just high demand  can slow down or even become unresponsive. Monitoring CPU usage and running processes gives you insight into what’s happening on your server like which processes are using CPU or memory, how busy the system really is, and whether something unexpected is causing trouble.

Useful Commands to Know

top — Real-time process monitoring

The top command gives you a continuous, real-time view of running processes and resource usage. It shows a table with columns like PID (process ID), USER (owner), %CPU (how much CPU that process is using), %MEM (memory usage), and COMMAND (process name).

You can also:

• Press P to sort by CPU usage,
• Press M to sort by memory usage,
• Press k then enter a PID to kill a misbehaving process,
• Change the screen refresh delay or iteration count.

This makes top a quick, powerful tool to spot and handle resource hogs.

htop — A more user-friendly alternative

If you prefer something more interactive and easier to read, htop is a great option. It has colored bars for CPU, memory, swap usage, and lets you scroll through processes, filter, and kill processes directly. 

On many systems, you’ll need to install it first:

sudo apt install htop

Once installed, just run htop, and you get a more intuitive “task manager”-style view.

ps — Snapshot of processes

While top/htop show a live, updating view, ps gives you a one-time snapshot of what’s running right now. 

ps aux

This lists all running processes. You can combine ps with other commands (like grep) to filter for a specific program.

If you want to find the top CPU-consuming processes in a quick snapshot, you might do:

ps aux --sort=-%cpu | head -n 10

This helps when you want to check CPU users without a constantly updating interface.

Advanced / Additional Tools

• pidstat (from the sysstat package) — gives per-process CPU (and optionally memory or I/O) usage over time. Useful if you want to track which process uses resources persistently.
• Other tools like vmstat, mpstat, iostat, etc., can help monitor CPU, memory, disk I/O, and more which is useful if you suspect performance issues beyond just CPU load.

Putting It into Practice — Example Scenarios

• Spotting a rogue process: Run top or htop, look for unusually high %CPU, note the PID or process name, then decide whether to kill or investigate further.
• Getting a quick system snapshot: Use ps aux or ps aux –sort=-%cpu to get a list of current processes and how much CPU they use.
• Tracking resource usage over time: Use pidstat (or system monitoring tools) to log CPU usage periodically.
• Checking overall system load: If CPU usage is high or system seems sluggish, these tools help reveal if the CPU is overwhelmed or if another resource (memory, I/O) is the bottleneck.

Conclusion

Monitoring CPU usage and processes in Linux doesn’t have to be complicated. With a few simple commands (top, htop, ps, pidstat, etc.), you can get an idea on what is happening inside your server. Whether you’re managing a server, debugging an application, or just curious about your system’s performance, these tools are very helpful. Using them regularly helps you troubleshoot problems, optimize resource use, and keep your system running smoothly.

If you’re finding it challenging to continuously track performance, troubleshoot resource spikes, or optimize server health, our expert team is here to help. At Skynats, we offer professional Server Management services designed to ensure smooth operation, real-time monitoring, and proactive issue resolution across Linux environments. Whether you need hands-on guidance or full ongoing support in Monitoring CPU Usage and Processes in Linux, our certified engineers are available 24/7 to assist.