[rrd-users] Best way to handle long delays between updates?

Simon Hobson linux at thehobsons.co.uk
Mon Nov 3 08:54:36 CET 2008

Coates, Jack wrote:

>I'm wanting to use Simple::RRD to build stats graphics from a 
>program that is intended to run infrequently (say once or twice a 
>day). I've got this working reasonably well, except that it's 
>showing single dots on the update times, and I'd like it to 
>extrapolate lines between the dots.
>What's the recommended best practice for this sort of usage? Should 
>I be adjusting frequency?

You probably don't have a long enough heartbeat time for your DS - 
thus after a delay, the data becomes unknown. If you increase the 
heartbeat time enough then the data will simply be normalised between 

>heartbeat defines the maximum number of seconds that may pass 
>between two updates of this data source before the value of the data 
>source is assumed to be *UNKNOWN*.

Whether this is what you want or not I don't know, but instead of a 
short 'blip' on the graph and nothing in between, you'll get a graph 
that just steps up or down at each update.
Simon Hobson

Visit http://www.magpiesnestpublishing.co.uk/ for books by acclaimed
author Gladys Hobson. Novels - poetry - short stories - ideal as
Christmas stocking fillers. Some available as e-books.

More information about the rrd-users mailing list