Consider the following raw data:

10:00 – 100
11:00 – 150
12:00 – 600

The following change rates can be derived:

?
+50/h
+450/h

Keeping the rates as a separate item seems somewhat inefficient for this task and is complicated due to ZBXNEXT-1049.

Without the separate item, if I wanted to trigger on a particular rate (s^-1), I can try to compare "(LAST minus PREV) / hardcoded interval" or even "DIFF / hardcoded interval". The problem there is, if the item interval changes or is not constant in the first place (trapping!), the result is wrong.

I would like to see a trigger function like the following:

Function | Parameter(s) | Supported value types
--------------------------------------------------------------------
rate | sec or #num | float, int

The rate of change in a period; The period is set in seconds or as a number of collected values (preceded by a # hash mark) in the first parameter.

The function accepts a second, optional parameter time_shift.