>The pre-processing step would aggregate data for the step size. It >would compute any desired aggregate data, like averages and >percentiles. The rrd table would then contain datasources for each of >the aggregate values.
It doesn't have to compute values for a whole step, as long as it performs an update no more often than once a second. You can feed in data more often than once/step and rrd will aggregate/normalise it over the step. >I was under the impression >that you could give it multiple values in the step and it would >compute some of the aggregate values. Over one step period, all aggregate functions are the same as the value. RRD normalises the data to arrive at a single value for the step period - aggregate functions then use only this normalised value. Eg, if you step is 300s (5 minutes) and the input type is gauge, you feed it 5 for one minute, then 0 for four minutes, this normalises to 1. Max is 1, Min is 1, Average is 1, Last is 1. If you wanted to see the 5 and 0 as Max and Min then you would need to use a smaller step size and have a 300s consolidation if you still want a 5 minute sample to be stored. -- 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. _______________________________________________ rrd-users mailing list [email protected] https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users
