Linux Process Statuses

When using ps with the “u” flag (ps -u) you will see a column called STAT that displays the process’s status.


The STAT column in the example below is outlined in red (using ps -aux):

ps -aux STAT example

Here is a list of the various process statuses and what they mean:

D – Uninterruptible sleep (usually a critical system process, a process that cannot be killed without rebooting)
R – Running or runnable (on run queue)
S – Interruptible sleep (waiting for an event to complete)
T – Stopped, either by a job control signal or because it is being traced.
Z – Defunct (“zombie”) process, terminated but not closed by the parent process that created it

Additional characters may be seen if in a BSD environment or when using the “stat” modifier with ps:

W – has no resident pages
< – high-priority process
N – low-priority task
L – has pages locked into memory (for real-time and custom IO)

  • 71 Users Found This Useful
Was this answer helpful?

Related Articles

How to List Compiled PHP Modules from Command Line

Pre-Flight Check These instructions are intended specifically for listing compiled PHP modules...

How to Install or Uninstall PECL Extensions

Pre-Flight Check These instructions are intended specifically for installing or uninstalling...

How to Install the MongoDB PHP Driver (Extension) on CentOS 6

Step 1: Setup Environment, Install PHP Extension & Application Repository (PEAR) As a matter...

How to Add a User and Grant Root Privileges on CentOS 6.5

Step 1: Add the User It’s just one simple command to add a user. In this case, we’re...

How to Add a User and Grant Root Privileges on Ubuntu 14.04

Step 1: Add the User It’s just one simple command to add a user. In this case, we’re...

Powered by WHMCompleteSolution