[rrd-users] Using a windowed counter

Marcelo Pasin webpasin at gmail.com
Thu Jun 15 13:05:22 CEST 2017


Thanks everyone for the answers, especially Alex for the long one. :-)

I will then write my own (window) interpreter for my rain gauge values.

Thanks! MP



> On 14 Jun 2017, at 01:07, Alex van den Bogaerdt <alex at vandenbogaerdt.nl> wrote:
> 
>> A far simpler solution is; it's just a counter that resets every hour.
> 
> No it's not.
> 
>>>> 011111244445678888889998767777765555553444335888889899987677
>>>> 010000120001121000121000012000110000010100012300011010001210
>                  ------------
>                   ------------
> 
> Look approximately halfway:  98767
> Then look below: 00012
> 
> The "counter" goes from 7 to 6, as a result of rainfall 1 being added and
> 2 being removed from the window.
> 
> If you treat this as a counter being reset every hour, you would get
> negative rainfall, or counter overflow with the resulting huge flood, or
> rates becoming unknown because of sanity checks.
> 
> 
> 
> 
> 



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