[rrd-users] Direct RRA updates

Tobias Oetiker tobi at oetiker.ch
Sun Nov 13 19:53:23 CET 2011


Hi Milan,

Today Milan Kr?má? wrote:

> Hello,
>
> I have the following idea: I would like to store statistics of a
> network interface (throughput in megabits per second) using RRD. Say
> the appropriate DS would be updated in minute intervals (it would have
> "step" set to 60 seconds). But the software which gathers the stats is
> able to read counters more frequently (for example once in every
> second), so it does not get only total (average) throughput for whole
> 60 seconds, but also minimum and maximum throughput withing the 60
> seconds (with 1 second time slot). Is there any possibility to store
> this information to the RRD as well?
>
> A similar scenario: ping a host every second but store only
> min/max/avg values every minute.
>
> I would like to create a single RRD file with step=60,
> RRA:MIN:steps=1, RRA:MAX:steps=1, RRA:AVERAGE:steps=1 and have all the
> RRAs updated in every step (providing 3 values).

> I know there is still possibility to create three RRD files, one for
> MIN, the second for MAX and third for AVERAGE, since all DSes in a
> single file share all RRA definitions, but is there a better solution?
> (Also, I don't want to simply set step to 1 second and update the file
> 60 times per minute).

this is what you would have todo ... if you want to optimize
performance, you could gather up 60 updates and hand them over to
rrdtool in one go, or if you want to go even further, set the MRHB
to 60s and then supply three fake updates, 1s min, 1s max and a
large 58s with whatever is necessary to create the right average.

> A side note: why, under usual conditions (not the example above),
> should I define RRAs with steps=1 for all the aggregates I want to
> then use with steps>1? (examine any RRD file with "rrdtool info" to
> see several RRAs with steps=1). RRA with steps=1 does not consolidate
> data, it only stores them: it is enough to have only one such a RRA...

yes it is enough ...

cheers
tobi

> Milan
>
> _______________________________________________
> rrd-users mailing list
> rrd-users at lists.oetiker.ch
> https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users
>
>

-- 
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


More information about the rrd-users mailing list