Hello Aleksandr, What you tell is very detailed. I don't know what is happening to your graph. I don't know if this will help you. But remember that rrdtool don't stores real data. I mean that maybe rrdtool is interpolating and that's why the graph is not as exactly as you think it should be. bye
2011/4/27 Aleksandr Pasechnik <aleksandr.pasech...@gmail.com>: > Hello all! > > I have an rrd collecting meteorological data. It has a step of 300 seconds > and data is fairly reliably entered every 150 seconds. There are times when > my computer is off and no data is entered. Explicit U's would be entered if > there was a problem getting the data, but I haven't encountered that yet. The > strange thing is that I have been getting these big, unexplained jumps in the > graphs (with corresponding strange numbers in the rrd dump) after blank > periods. The parameter in question (it happens to the others sometimes, but > for some reason this last time it only manifested in this one) is the > atmospheric pressure. It is stored as a GAUGE with a heartbeat of 600, a min > of 0 and a max of U. I've got some RRA's, namely Average, Min, and Max at xff > 0.1, 1 data point, and 7340 rows (30 days of data i think); and xff 0.5, 12 > data points, and 44040 rows (5 years of data). I'm currently plotting the > last 24 hours of data with a resolution of one pixel per data point. Before > the blan > k occurred, my script was writing 1015.8 into the pressure. Once the > computer came back up, it was entering 1012.8 and 1012.4 (a bit of sensor > noise between measurements i suppose). At no point did i write a 1008.9 or > whatever its plotting there. Here is the offending graph output: > > http://russkey.tumblr.com/post/4971101013/jumping-rrdtool > > Any thoughts why this is happening? Anything I can do to stop it? I thought > it might have something to do with the xff, so i changed it from 0.5 to 0.1 > for the 1 data point per row RRA's but that doesn't seem to have helped. > Though now that I think about it, perhaps it would make more sense to have > just a single RRA for the 1 data point per row section, and have it a Last > instead of an Average? Any help at all would be appreciated! > > Al > _______________________________________________ > 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
