[rrd-users] More observations and questions on COUNTER

[Philip Peake]

On 10/24/2010 12:48 AM, Simon Hobson wrote:
>
>> 3.	I really wanted the stored values to be the same as the input 
>> values. They obviously are not, which seems odd since the sample 
>> period is 30 seconds, and I take great care to ensure that the 
>> values sampled as close to 30 seconds apart as I can, and then 
>> entered with a time set to a 30 second boundary. I thought this 
>> should ensure that the stored value would be precisely the 
>> difference between the current and previous value.
> Can you point out anomalies ? I've had a very quick look and the 
> numbers seem about right to me. You do understand that RRD tool only 
> ever stores rates don't you ?
> Ie, updates of :
>
> 1287866340:80740899
> 1287866370:80741789
> 80741789 - 80740899 = 890
> 890 / 30 = 29.667
>
> value stored :
> 1287866370: 2.9666666667e+01
>

So you are saying the rate is always per second?
I thought it was rate per <sample period> ??

So a value stored at the exact end of a sample period would be equal to
the value presented.