Response Time Calculations

dudds

Hi Guys,

I'm after some confirmation as to how the response times for a node are calculated for the various graphs in NPM. For example if I change the default polling interval for all nodes to 30 seconds and then go to the node details page of the and then look at the average response time graph for today (5 min interval) what is this actually telling me? If the poll interval is 30 seconds then there would have been 10 polls in that 5 minute period. Will NPN take the average of these 10 polls and then this is the value plotted in the graph, or does it just plot the last poll.

 

Thanks, 

mark_wiggans

 Orion charts show data points that are aggregations of specific time periods. For instance, you can configure a chart to show a 24-hour time period in 30-minute increments, for a total of 48 data points. Each of those data points (if you're polling once every ten minutes) could represent three specific polls of that device. Therefore, the minimum, maximum, and average values could be different.

As for performance, you must first understand that a "last 5 minutes" chart will likely show no more than one data point, since the default polling interval for interfaces is greater than five minutes. This being said, performance of the charts is going to be tightly bound to performance of your SQL server, so you'll want to make sure that your SQL server is tuned well. I've not encountered any performance problems with Orion charts on individual devices; however, summary charts do take a while to generate since they represent a much larger data set.