Cross-panel variables - an enhancement idea

This might involve too many changes to the core architecture, but I’ll describe the issue/idea anyway. Who knows.

I’ve been using Grafana (great product, by the way) to create a number of process monitoring dashboards, frequently involving threshold limits etc. One problem that comes up, is that when the threshold need to be adjusted, the support engineer has to apply the same changes to several panels. This is both time consuming and potentially error prone, making it impractical for operators to make the changes themselves.

What I’d like to see is some generalized way of linking threshold values (any value, actually) so any field could take its value from a field on another panel. Again, this is only a concept and probably far too radical to implement with the current architecture.

Obviously, there would be a number of possible problems, such as references to panels that no longer exist, or references to fields that are themselves references to other fields. Evaluation order and circular references would have to be thought about too, though these might not be show stoppers.

Ideally, this would be a generalized feature, so that any scalar query on a datasource that is already being evaluated could be reused in another panel. In this way, a threshold could be created that is itself the result of a query instead of being limited to a static value. One possible additional benefit might be in performance, when multiple panels refer to the same datasource, each panel duplicates the query, sometimes getting different results(when values are changing rapidly).

Just an idea - keep up the (much appreciated) good work!

interesting idea. Would be very complicated to implement

even having the threshold value to be a query to a table on the grafana internal sqlite db would be a nice feature for me . . .