---
title: ps — view running processes
date: 2026-10-17
time: 12:00
model: admin
category: programs
author_type: human
summary: A command that checks currently running processes. Examples include aux/-ef combinations, sorting by memory, checking processes, and execution screens.
tags: program, Service and process management, ps
---

**💬 "ps command"**

- **Concept**: Shows the list of processes currently running on the server. You need to know the PID to terminate them with `kill`.
- **Output structure**: The columns vary depending on the options. By convention, `ps aux` or `ps -ef` is commonly used.
- **Recommended output for practical use**: If you want to see only the columns you need, select and output them like `ps -eo pid,user,%mem,cmd`.
- **PID column**: This is the process number. It is the value used when running `kill`.
- **%MEM / %CPU columns**: These are memory and CPU usage. Sort in descending order with `--sort=-%mem`.
## 3 Essential Command Combinations

- `ps aux` — View all processes with user, CPU, and memory usage
- `ps -ef` — View processes including the parent PID (PPID)
- `ps aux | grep nginx` — View only a specific process
Here are some options worth knowing as well.

- `--sort=-%mem` — Sort by memory usage in descending order
- For periodic checks, `top` or `htop` is convenient.
**💬 "Make an example based on a situation beginners often encounter"**

**Scenario**: The process of checking how many web server processes are running.

### Step 1: Search for processes

Find processes related to nginx.

```
ps -ef | grep nginx
```

### Step 2: Count the processes

Count the number of workers.

```
ps -ef | grep nginx | grep -v grep | wc -l
```

### Step 3: Check the parent process

Check the master process PID.

```
ps -eo pid,ppid,cmd | grep nginx
```

## Actual Output

This is an example screenshot of viewing processes with `ps aux`.

![ps command execution result: PID, user, CPU and memory usage, command](https://games.aidebatehub.com/assets/ps-demo.png)

Actual production server

---
Source (HTML): https://games.aidebatehub.com/programs/linux/services/ps.html
This file is an auto-generated Markdown twin of the DevHub document.