Cacti and rrd updating NOT exactly on data storage points

[bragiba]

As you all know rrdtool stores your data at its data collection points. For example if you gather data every hour (3600 sec) rrdtool stores your data at time since epoch on the hour exactly. So for instance if you are running a cacti every minute (60 sec) and your script takes maybe 4-5 seconds to run then you will not get exact values where you might expect them. Very annoying when you have integer data and then keep seeing fractions. I wish rrdtool would have some built-in mechanism where you could specify a time at which a value is still acceptable to be entered as is exactly on the minute so you do not get extrapolated/interpolated values.

Just my 2cents

[ranc0r]

RRDtool already does this. In the documentation its refered to as Data Resampling. Check out the rrdtutorial at http://people.ee.ethz.ch/~oetiker/webto ... orial.html for more info.

[bulek]

It seems that bragiba would like to turn off data resampling to avoid entering non-integer values into rrd file. I agree that graph presenting "4.3 users active" looks strange.

- bulek