[rrd-users] I have what i hope is a simple question

Simon Hobson linux at thehobsons.co.uk
Tue Jun 29 10:10:00 CEST 2010


Jack Tavares wrote:

>Maybe I haven't had enough coffee yet this morning, but I am having 
>trouble figuring this out.
>
>I put in a DERIVE type for "transactions" and CF using averages.
>That give me a nice graph for the transactions / second.
>
>What I also want is the total transactions for a given period. (not the rate)
>I can compute that from the average, but there is going to be some 
>precision loss.

Unless you are very careful in how you enter data, it is all 
normalised anyway. Values are held to a fairly high precision, so 
multiplying the resultant rate by the time will give you a fairly 
accurate result. There isn't any other way - RRD tool does not store 
actual values, everything is converted to a rate.

You can minimise errors by ensuring that you enter data exactly on 
every step boundary, and exactly on those step boundaries - that way 
normalisation is a null operation.

-- 
Simon Hobson

Visit http://www.magpiesnestpublishing.co.uk/ for books by acclaimed
author Gladys Hobson. Novels - poetry - short stories - ideal as
Christmas stocking fillers. Some available as e-books.



More information about the rrd-users mailing list