[rrd-users] DST ABSOLUTE does not work as expected

[Stefan Wernli]

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[Tobias Oetiker]

I'm reading a value minutes of sunshine in the past 10 minutes, which can vary between 0 and 10 and gets read every 10 minutes.
So I created an rrd with a DST ABSOLUTE, because the source always starts at 0 after each period, expecting the value in the RRD to be like
10,20,30,40,50,60 for a full hour of sunshine.
 
 
ds[sunshine].index = 1 ds[sunshine].type = "ABSOLUTE" ds[sunshine].minimal_heartbeat = 1200 ds[sunshine].min = 0.0000000000e+00 ds[sunshine].max =
1.0000000000e+10 ds[sunshine].last_ds = "10" ds[sunshine].value = 0.0000000000e+00 ds[sunshine].unknown_sec = 0
 
 
<!-- 2015-03-28 08:50:00 CET / 1427529000 --> <row><v>1.6666666667e-02</v></row> <!-- 2015-03-28 09:00:00 CET / 1427529600 -->
<row><v>1.6666666667e-02</v></row> <!-- 2015-03-28 09:10:00 CET / 1427530200 --> <row><v>1.6666666667e-02</v></row>
 
(1.666e-02 is 1/60 btw.)
 
 
What point am I missing?

rrdtool always deals with rates ... so if your input is minutes of
sunshine in 10 minute interval, I would log that value times 60.

If you then want to see sunshine per hour, you simply multiply the
number stored by 3600

cheers
tobi