Querying the precomputed result will then often be much faster
than executing the original expression every time it is needed.
This is especially useful for dashboards,
which need to query the same expression repeatedly every time they refresh.
Recording and alerting rules exist in a rule group.
Rules within a group are run sequentially at a regular interval,
with the same evaluation time.
The names of recording rules must be
valid metric names.
The names of alerting rules must be
valid label values.
Every evaluation cycle this is evaluated at the current time,
and the result recorded as a new set of time series with the metric name as given by 'record'.
Recording rules allow you to precompute frequently needed or computationally expensive expressions and save their result as a new set of time series.