[rrd-users] Questions of new user

rrd-users at ficos.de rrd-users at ficos.de
Sun Dec 6 12:49:59 CET 2009

>>>> if you update more often than required for you step size, the data will
>>>> be aggregated using the aggregation function you've chosen (MIN, MAX,
>>>> AVERAGE etc) so either the smallest or the highest or the average of the
>>>> values will be stored.
>>> No, the aggregation functions are NOT used for sub-step updates.
>>> See Alex's tutorial on rates and normalising - it's all explained well
>>> there.
>>> http://www.vandenbogaerdt.nl/rrdtool/
>> Actually I did not really describe sub-interval updates.  And I don't know
>> from the top of my head. I'd have to look in the sources to see what really
>> happens when you do that.
> Well it's "sort of" in there, but not really highlighted. If you 
> update every second with a step size of 60, then you can feed in one 
> value of 60 and 59 values of 0 - and get the result of 1/second for 
> the step. Min. Max, etc only come in when consolidating PDPs.
> That's what I've observed anyway.

Agreed. That's what I've observed, too. Sorry for the somewhat misleading info
in my first reply. I'm using mostly AVERAGE as aggregation function, so I got
confused myself, but aggregation happens at the RRA-entry-level. For PDPs it
seems to be always average.

- Karl

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