[rrd-users] A reason there isn't a CF SUM function?

Simon Hobson linux at thehobsons.co.uk
Tue Aug 21 20:00:24 CEST 2012

Derek Haynes wrote:
>  > That makes sense. You will only get one value by summing a list of numbers.
>>  Which leads on to ... what would you store for a SUM CF ?
>Instead of averaging the known values, calculate the sum. For example,
>if I have an RRD file w/1-min RRAs and I want to fetch at a 30-minute
>step (lower resolution across a large time frame), I'd be looking for
>the sum of each RRA value during each 30 minute interval.

Which you can get with :


Where ${res_step} is the length of the consolidation interval being 
used. In your example, 1800 seconds.

What might be more useful might be an option to handle unknowns 
differently during consolidation.

Simon Hobson

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