Calculates the per-second rate of change between consecutive data points. It divides the difference in values of consecutive data points by the difference in their timestamps (in milliseconds) and then multiplies the result by 1000 (to scale up the quantity from a per-millisecond rate to a per-second rate).
The rate operator also assigns the value of the metric tag to be
rate($metric) and the value of the unit metadata field to be
$unit/second (for example, 1/second).
metric query | rate
This query calculates the increase or decrease per second in the
Net_InBytes metric from one collected data point to the next.
metric=Net_InBytes Interface=eth0 | rate