I understand that this topic has been posted before - but my understanding wasn't perfectly clear after reading those posts. Also I read the tutorials on the website and also those those by Alex - but I still have a doubt as to how these parameters relate / work with one another. I apologize for the double posting but I only do so in the interest of clarity. I hope other newbies like me benefit from this post.
I expected to get the value of 5 at 1314274800 but I get NaN. I understand that RRDTool does the following before it stores values: Rates, Normalization, Consolidation. In this case my DS is a GAUGE so it is a rate - no conversion is required here. I am normalizing stuff every 300 seconds (step is 300) beginning from the start time of 1314270000. I then have a CF of AVERAGE that is averaging 1 value. So in this case, I am not really averaging anything.
update at times 1314272400 and 1314274800. The difference is 2400 seconds.
That is more than the heartbeat, thus is the rate unknown between
1314272400 and 1314274800. Now this unknown goes into normalization and
consolidation. All parameters like X-Files Factor, step, steps play a role
only after heartbeat did its work.