[rrd-users] newbie rrd question - probably a very old issue

[Alex van den Bogaerdt]

On Fri, Aug 31, 2007 at 10:06:24PM -0400, Dan Gahlinger wrote:

> you may be correct that we are asking it to consolidate, and we don't want 
> to. we simply don't know.
> it just seems, totally wrong.

If you have 400 pixels on the graph, and you have 4000 averages to display,
it won't fit. Somehow you will have to combine 10 intervals into one.
If you don't, then rrdtool will.

> what's the point of defining so many data points if its going to 
> consolidate it anyhow?

With many datarows you can look back in time at the highest possible
resolution. You won't be using all of the data, just a portion of it.

Consolidated data can be used to quickly report on a longer interval,
without having to wait for rrdtool to do "consolidation" on the fly.
No need to reduce 4000 rows into 400, if you already have the data
available in a more appropriate resolution.

They both serve a purpose.


> we have learned it is NOT the graphing function doing it, though.

then it has to be another available RRA.

> if we look at the raw data it is correct, but if we query the data, we get 
> the consolidated results.
> it shouldn't be consolidating.

Then you shouldn't have defined that RRA.

More likely you should have created another RRA, or if you did, you should
be using it.  If you want to see maxima, then you should use the MAX RRA,
not the AVERAGE RRA.
(capitals not for shouting, but because that's how it's written!)

-- 
Alex van den Bogaerdt
http://www.vandenbogaerdt.nl/rrdtool/