my grafana request SELECT derivative(mean(“value”), 1s) FROM “jmeter.all.h.count” WHERE $timeFilter GROUP BY time($__interval) fill(null)
And here is what i can see on jmeter with its hits/sec plugin
In my grafana dashboard i don’t understand why I get negative values.
Actually on grafana and jmeter, i almost get the same graph but not with the same scale.
Any thoughts to help me out?
In my jmeter, I have a big transaction SC01 which include many small transactions TRXX.
Do you think hits/sec should be retrieve with the transactions?
Sorry for my late reply. I can’t tell you right now if it works because I don’t have access to the testing platform. When I’ll do it, I’ll let you know the result and will remove this comment.
Thanks for your understanding.
I have been dealing with the same sort of issues, and have two suggestions for you to try.
First, try using the non-negative-derivative function instead of just the derivative function. I believe that takes the absolute values when calculating.
Next, you may just want to do the old-fashioned rate calculation with the math function. Try to sum your data points over a group interval of 1 minute, then using the math function, divide by 60. If your datapoints are grouped by smaller intervals you have to change the value to use (10s, then divide by 10). This is not an ideal way to do it, but from my experience is gives reasonably similar results to rate functions calculated elsewhere.
