Kevin Stewart <[email protected]> wrote:

> Once an RRD is created, as points are added, will the file grow over 
> time? Or does the file stay the same size (given that is is not tuned)?

As Pablo says, they are pre-allocated and stay the same size - that size is 
known because you define all the DSs (data series), consolidations, and 
retention periods (ie number of consolidated data points to keep) when you 
create the file. Internally it is as the name says, a round robin. Each 
consolidated data set is defined by a single list of values - plus a pointer to 
the current "start/end". As new data comes in, it simply over-writes the oldest 
data and the pointer moved on - when the pointer gets to the end, it wraps 
around to the beginning. So nothing is "added" or "removed" - only updated 
in-place.

However I'm not sure what you mean by "not tuned" - because RRD files are 
actually quite highly tuned for a specific purpose, that of efficiently 
storing/extracting/graphing predefined sets of data as above.

As a bit of trivia, RRD Tools came out of the MRTG project - a set of tools to 
collect, consolidate, and graph interface traffic rates for routers (hence 
Multi Router Traffic Grapher).

_______________________________________________
rrd-users mailing list
[email protected]
https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users

Reply via email to