The default RRA stores primary data points for an hour. More RRA can be added for a day, a week, a month, a quarter and a year. The created RRD is for an acquisition period much less than an hour, typically about some seconds or a few minutes.

This constructor neads an argument named step which is the period of acquisition which is second(s) or minute(mn).

    $creator = new RRDTool::Creator::HourPDP(-step => "30s") ;
    $creator->add_RRA(-duration => "day") ;
    $creator->add_RRA(-duration => "week") ;
    $creator->add_RRA(-duration => "month") ;
    $creator->add_RRA(-duration => "quarter") ;
    $creator->add_RRA(-duration => "year") ;