If you are getting the
No activity within 1440 seconds; please log in again message it means that your
phpMyAdmin session is set to expire in 1440 seconds by default. In order to extend phpMyAdmin timeout with a
longer one, you need to change your php and phpMyAdmin configurations.
For Ubuntu 13.10/13.04/12.10/12.04:
you will need to change your php settings as well.
Finally restart your server for changes to take effect, for this example I will assume you are using apache.