[rrd-users] Standard Deviation Graph

[Tobias Oetiker]

Hi Sooraj

there are no built in provisions for calculating a std deviation,
but using CDEF and the PREV directive you should be able to create
something along the lines you desire ...

if you are just after numeric results, you cal also use rrdtool
xport to grab data from the rrdtool databases and use some
scripting to implement the calculations ...

cheers
tobi


Yesterday Sooraj S wrote:

> Hi Everyone,
>  I'm new to rrdtool and this users list. I have a task in my hand for which
> i would like to get your valuable suggestions. I have a data pipeline to
> monitor. I will be storing the sent, received_good values for every minutes
> in an rrd for each server. I would like to plot a Standard Deviation Graph
> for this system (also an alerting system) which compares this hour's data
> (sent and received data will be considered seperately for monitoring) with
> historic data for the same hour (like prevoius day same hour, previous week
> same day same hour, previous month same day same hour, prev year same day
> same hour). As of my understanding rrd averages the old data. So what would
> be the best strategy for me here ? Also like to know from you the use cases
> of Standard deviation in rrd.
>
> ---
> Thanks,
> Sooraj
>

-- 
Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten, Switzerland
http://it.oetiker.ch tobi at oetiker.ch ++41 62 775 9902 / sb: -9900