ps

List processes

What it does

ps aux lists every process on the system: the user, the PID (process ID), CPU and memory use, the start time and the command. The letters go without a dash: an old BSD style of flags.

The list is long, so you filter it: ps aux | grep nginx. The grep itself shows up in the result, and that is normal. pgrep -a nginx does the same more briefly, printing just the PID and the command.

Syntax

ps aux
ps aux | grep <name>
pgrep -a <name>

Examples

• List every process on the system

  ps aux

  • ps — list processes
  • aux — of all users, with owners, background ones included

• Find the nginx processes and their PIDs

  ps aux | grep nginx

  • ps aux — every process
  • | grep nginx — keep the lines with nginx

Related commands

• top — Watch the system load and processes live
• kill — End a process by its ID
• grep — Find the lines with some text in files

Practise · All commands