You just created a system user which runs the Cacti poller and scheduled the poller to run every 5 minutes. Five minutes is the default interval, but it can be changed to 1 minute if needed. For more information on how to do so, go the following post in the Cacti forums: http://forums.cacti.net/viewtopic.php?p=116403.
Installing the Spine poller
By default, Cacti comes with a poller written in PHP. For small-to-medium installations, this poller does its job just fine, but for larger installations, an alternative poller, spine, needs to be used. It is written in C and is much faster than the original poller, as it makes use of the multi-tasking capabilities of modern operating systems and hardware.
Here we will deep-dive into installing and configuring the spine poller.