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2007-11-12 #2

Created by dave. Last edited by dave, 11 years and 34 days ago. Viewed 1,380 times. #2
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RRDs

Started trying to load data into the RRDs.

Renamed x2 to import.

Doing RRDs under perl is incredibly wordy.

RRDs don't seem to like IP addresses as DS names; ie this fails:

RRDs::create ("$RRD/$ip.rrd", "--start=$creationTime", "DS:$ip:GAUGE:300:U:U",
    ...);
...but change the $ip to bytes in the DS string and it works.

Contemplating giving import a flag that will kill both any pre-existing RRDs and drop/regenerate the postgres table. This will make re-runs better. Either that or I should write a short script to do the kill and database table dropping/recreating.

I think I read somewhere that you have to write to RRDs in ascending order of time: ie if you write one time period, you can't write any time periods before then. So you have to sort your data prior to writing it out. My quick whack at this didn't work so I'll have to look at it later.

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