I'm with Simon on the validity of normalized input. If your device will never report fractions of a degree, then the input will almost always be "wrong" anyway, and certainly not more correct than what RRDtool eventually produces.
This said... Setting step to one is a good first step. Next try to NOT have an RRA where steps==step, and NOT with consolidation function average. There is nothing wrong with, for instance, setting steps==3600 and CF==MAX to remember the highest temperature reported during an hour, and to have this as the RRA with finest granularity. You could have two RRAs, one remembering MAX the other MIN, and then show the temperature range seen suring any hour (e.g. a red area for the max temperature seen, overlayed by a blue area for the minimum temperature seen). Not sure if cacti can do this, that's for someone else to answer, but RRDtool can do it. HTH Alex ----- Original Message ----- From: "ENTRESSANGLE, ERIC (ERIC)" <eric.entressan...@alcatel-lucent.com> To: <rrd-users@lists.oetiker.ch> Sent: Tuesday, February 18, 2014 3:17 PM Subject: [rrd-users] Input values normalization Hello I would like the feedback of experienced rrdtool/cacti users about the following point : I think I understood that rrdtool works with rates (through counter, derive, absolute types), and that in this case, the "normalization" step can make sense. But I'm more doubtful about the "normalization" for gauge type, for example when I graph a plain temperature, because it means that the temperature on my graph is never exactly the real input value, unless data source step and cacti's poller are perfectly synchronized, but it is impossible when there are a lot of counters to retrieve. The solution I found is to set a data source step to 1 second to avoid normalization, but this produces big rrd files with a lot of redundant information. I did not find a satisfactory solution up to now, thanks for any hint. Regards Eric -------------------------------------------------------------------------------- > _______________________________________________ > rrd-users mailing list > rrd-users@lists.oetiker.ch > https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users > _______________________________________________ rrd-users mailing list rrd-users@lists.oetiker.ch https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users
