We have a LLD with several item prototypes, some of which have preprocessing steps configured. In particular, for two item prototypes we have a single step configured consisting of a custom multiplier. Now, when a new actual item is created from either of these prototypes, we noticed that the first (and only the first) value stored is the raw value without preprocessing - all subsequent values, however, have the custom multiplier correctly applied. This is causing a number of spurious triggers and alerts in our setup.
To recap, the following should be sufficient to reproduce it:
- Create a LLD
- Create an Item Prototype, of type Numeric, and configure it with a single preprocessing step consisting of a custom multiplier
- wait for an item to be created and a few values to be stored
- look at the values and notice that the first one does not have the custom multiplier applied to it, but the rest do