How to log MRTG report by Packet (pps)

How can I log the MRTG report by packet per second ?
Thank you.

/interface print
/interface print oid

Do you mean I need to use third-party tool to monitor the router remotely via SMTP ?

Like this : http://www.mikrotik.com/testdocs/ros/2.8/appex/mrtg1_content.php

Thank you .

MRTG is ‘third-party tool to monitor the router remotely via SMTP’

yes, use the examples you linked to