We don't have the
ability to
alert on metrics polled as 'graphs' yet. I'm still trying to
work out how
best to do it.
I would think something along the lines of Graphite's queries for
moving averages over a timespan would be a good start. Which of
course begs the question -- does it make any sense to use Graphite
as the backend instead of RRD? Huge change, granted, but it is much
more scalable among other nice attributes. More machinery, though.
Without actually using Graphite, would it be even reasonable to add
a checker type linked to a RRD query? I am guessing it would be too
much load past a handful of checks.