How to monitor usage of system resources in a period of time using atop

Question

How to monitor the usage of system resources in a period of time using atop?

Answer

I. Installation & setup

1. Connect to the Plesk server via SSH.

2. Install the atop package:

   • on CentOS/RHEL-based distributions:

     # yum install atop

   • on Debian/Ubuntu-based distributions:

     # apt-get install atop

3. Set monitoring interval to 60 seconds (the default value is 600 seconds):

   • on CentOS/RHEL-based distributions:

     # sed -i 's/600/60/' /etc/sysconfig/atop

   • on Debian/Ubuntu-based distributions:

     # sed -i 's/600/60/' /etc/default/atop

4. Start the atop service:

   # service atop restart

   Note: On Debian/Ubuntu-based distributions, atop automatically creates a cron task that starts logging automatically at midnight if it is not running.

II. Usage

1. List generated atop logfiles:

   # ls -l /var/log/atop/

2. To view the collected data, run:

   # atop -r /var/log/atop/atop_*****

   where atop_***** is a file name from step 1.

3. To switch between the intervals, use the hotkeys:

   • t - move forward

   • Shift + t - move backward

   • r - reset all counters

     Note: To learn more about atop hotkeys, see this atop man page.

    

   To disable atop, run:

   # service atop stop

   On Debian/Ubuntu-based distributions:, remove the atop cron task:

   # rm -f /etc/cron.d/atop