Every administrator knows that a system can begin to slow down as a result of heavy disk I/O activities. However, in the role of a troubleshooter you will probably want to know which processes or (in the case of multi-user systems) which users are the culprits that and it is for this reason, you will want to turn to iotop—a tool that shows a list of the most I/O intensive processes in real time in a top-like interface.

To begin with, you will need to install iotop by typing:

# yum install iotop

The download is only small, and to start a discovery session, simply use the following command:

# iotop

Running iotop without any arguments will result in a list of all existing processes regardless of their disk I/O activities, so if you want iotop to only report on processes that are committed to disk I/O activity, you should use the following instead:

# iotop –o

The output is verbose as it works in a way similar to the top command, so familiarity should make you feel...