Tobias Oetiker <tobi <at> oetiker.ch> writes: > > Hi Peter,
I hope it is not considered unpolite to reply to this very old post, but I didn't find anything really applicable after this... > what Alex says about time stamps I agree with (I think), so if you > see data with a time stamp then this means that it is valid for > the interval ending at that point in time so if the time stamp says > 11:00 then the data associated with it is valid between 10:55 and > 11:00 (assuming a 300 second step) OK, if I get it the value returned by fetch or put in a graph at a point in time represents what happened in the previous interval up to that point in time. Makes sense. > As for the amount of data fetch returns, the intended behavior is > for it to return enough data to 'cover' the requested time > interval at a resolution equal or better than requested ... I don't fully get it. Reading through some tutorials (e.g. http://www.vandenbogaerdt.nl/rrdtool/tutorial/rrdcreate.php) it seems that it would be wise to calculate the number of items to store in a RRA according to the number of pixels that we want in the final image. So, being able to calculate the exact number of items that a query would get can actually make a difference. As I see it in 1.4.7, if I have: --start a multiple of $step --end=start+$(($N * $size)) I will get $N+1 items, so I should plan my graph to actually be $N+1 pixels wide. Should I upgrade to something different? Thanks, Flavio. _______________________________________________ rrd-users mailing list [email protected] https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users
