How to Use ps aux Command in Linux: Syntax and Examples
Use the
ps aux command in Linux to display all running processes with detailed information like user, CPU, and memory usage. The ps command shows process status, while aux options list all processes for all users in a user-friendly format.Syntax
The ps aux command combines three options:
a: Show processes for all users, not just the current user.u: Display the process's user/owner and detailed info.x: Include processes not attached to a terminal (background processes).
Together, ps aux lists all running processes with useful details.
bash
ps aux
Example
This example runs ps aux to show all processes currently running on the system with columns like USER, PID, %CPU, %MEM, VSZ, RSS, TTY, STAT, START, TIME, and COMMAND.
bash
ps aux
Output
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.1 169084 5404 ? Ss 10:00 0:01 /sbin/init
user 2345 0.1 0.5 256000 21000 pts/0 S+ 10:05 0:00 bash
user 2350 0.0 0.3 150000 13000 pts/0 R+ 10:06 0:00 ps aux
Common Pitfalls
Common mistakes when using ps aux include:
- Running
pswithout options, which shows only processes for the current shell. - Confusing
ps auxwithps -aux, where the dash changes behavior and may cause errors. - Not using
grepto filter output when looking for specific processes, leading to overwhelming output.
Always use ps aux without a dash before aux for correct results.
bash
ps -aux # Incorrect usage ps aux # Correct usage
Output
ps: invalid option -- '-'
Try 'ps --help' for more information.
Quick Reference
| Option | Meaning |
|---|---|
| a | Show processes for all users |
| u | Display user-oriented format with detailed info |
| x | Include processes without controlling terminal |
Key Takeaways
Use
ps aux to list all running processes with detailed info on Linux.Do not add a dash before aux;
ps aux is correct, ps -aux is not.Combine
ps aux with grep to find specific processes easily.The output columns include user, process ID, CPU and memory usage, and command details.
Remember
a, u, and x options together show all processes comprehensively.