[rrd-users] rrd create --start date; internal treatment

[Filip Moritz]

Hi.


With rrdtool create, --start sets a boundary for the earliest accepted values. I assumed this timestamp would be stored inside the rrd metadata, now it apears it isn't. Is this correct? Is there any way to recover start/creation time from an rrd file?

Moreover: How is start time treated internally? It seems unknown values before start time get involved in aggregation: Time frames overlapping start time either become unknown or the unknown values padded leading to exaggerated values especially for time-series starting with high peaks (here: hits on online news articles).

Talking workarounds: Is there an option to create rrds with pre-zeroed values?

Does anyone know good resources or maybe some thread subjects on the use of rrd with very infrequent updates?


thx.
g., fil