[rrd-users] Using Granular RRA Automatically

[Simon Hobson]

Stephen R Guglielmo <srguglielmo at gmail.com> wrote:

> If I were to do something
> like the following:
> 
> rrdtool create filename.rrd \
>  --step '86400' \
>  'DS:Sites:GAUGE:172800:0:U' \
>  'DS:DeletedSites:GAUGE:172800:0:U' \
>  'DS:OutdatedSites:GAUGE:172800:0:U' \
>  'DS:Users:GAUGE:172800:0:U' \
>  'RRA:LAST:0.3:1:3660'
> 
> This will basically keep every single value entered for 3660 days (~10
> years), correct? It won't consolidate any values?

Correct.

> I understand this
> will have increased disk usage in the .rrd file, but are there any
> other downsides to doing this?

For this application, I don't think so.
In general, it's a trade-off between the amount of data retained (ie how far back you can go vs how detailed it is), disk usage, and resources needed to draw graphs.
So if you were to keep (say) traffic for every 5 seconds for the last 10 years with no consolidation, then drawing graphs would be very I/O and processor intensive as it would have to do a lot of consolidation to generate the graph (as well as taking a lot of disk space). In your case, even keeping unconsolidated data for 10 years, it's not a large amount of data, and unless youre system is very resource constrained, I doubt it's going to make any difference.