On Fri, Apr 04, 2008 at 11:53:15AM +1300, Max wrote: > I am happy enough with the daily graphs, but I must be recording the > data wrong somewhere, as the graphs for longer periods are not showing > the Max or Min of the temperatures, but I suspect are averaging them out > over a longer period (i think). > > This is naturally one of those problems of the dam computer doing what I > ask it to do, rather than what I want it to do.
Indeed. You ask it to show averages. > I'm hoping it is a simple mistake, and somebody can show me the errors > of my way, though I suspect I will have to lose all the data I have > collected so far :( That depends. If you remember correctly, you do store MIN and MAX rates. If so, you can start using them and nothing's lost. > rrdtool graph /var/www/rrdtool/temperature-day.png \ > DEF:in1=/var/www/rrdtool/temperature.rrd:internal:AVERAGE \ > DEF:in2=/var/www/rrdtool/temperature.rrd:inside:AVERAGE \ > DEF:out=/var/www/rrdtool/temperature.rrd:outside:AVERAGE \ > VDEF:MaxIn1=in1,MAXIMUM \ This is the maximum of all averages. You want the maximum of all maximums. > VDEF:MinIn1=in1,MINIMUM \ This is the minimum of all averages. You want the minimum of all minimums. Suggestion: a couple more DEFs: > DEF:in1min=/var/www/rrdtool/temperature.rrd:internal:MIN \ > DEF:in2min=/var/www/rrdtool/temperature.rrd:inside:MIN \ > DEF:outmin=/var/www/rrdtool/temperature.rrd:outside:MIN \ > DEF:in1avg=/var/www/rrdtool/temperature.rrd:internal:AVERAGE \ > DEF:in2avg=/var/www/rrdtool/temperature.rrd:inside:AVERAGE \ > DEF:outavg=/var/www/rrdtool/temperature.rrd:outside:AVERAGE \ > DEF:in1max=/var/www/rrdtool/temperature.rrd:internal:MAX \ > DEF:in2max=/var/www/rrdtool/temperature.rrd:inside:MAX \ > DEF:outmax=/var/www/rrdtool/temperature.rrd:outside:MAX \ and change the VDEFs: > VDEF:MaxIn2=in2max,MAXIMUM \ > VDEF:MinIn2=in2min,MINIMUM \ > VDEF:AvgIn2=in2avg,AVERAGE \ and so on. Why? Average RRA's work like this: RRA 1: 10,11,12,10,9,8,11,12,13,12,10,8 -> 10,11,12,10,9,8,11,12,13,12,10,8 RRA 2: (10,11,12), (10,9,8), (11,12,13), (12,10,8) -> 11,9,12,10 RRA 3: ((10,11,12), (10,9,8)) , ((11,12,13), (12,10,8)) -> 10,10 max(10,11,12,10,9,8,11,12,13,12,10,8) == 13 max(11,9,12,10) == 12 max(10,10)==10 min(10,11,12,10,9,8,11,12,13,12,10,8) == 8 min(11,9,12,10) == 9 min(10,10)==10 Now using the MAX rra: RRA 1: 10,11,12,10,9,8,11,12,13,12,10,8 -> 10,11,12,10,9,8,11,12,13,12,10,8 RRA 2: (10,11,12),(10,9,8),(11,12,13),(12,10,8) -> 12,10,13,12 RRA 3: ((10,11,12),(10,9,8)),((11,12,13),(12,10,8)) -> 12,13 max(10,11,12,10,9,8,11,12,13,12,10,8) == 13 max(12,10,13,12) == 13 max(12,13)==13 Similar for the MIN rra. HTH -- Alex van den Bogaerdt http://www.vandenbogaerdt.nl/rrdtool/ _______________________________________________ mrtg mailing list [email protected] https://lists.oetiker.ch/cgi-bin/listinfo/mrtg
