Increase/delta calculation with missing datapoint at range beginning

[Vincehood]

Hello,

My question is the following:

I have a metric with type ‘counter’.

I am interested to calculate how much it increases during a 10 min range but datapoints are missing at the beginning of  the range. For example, the counter metric was initialized later or Prometheus was down for some reason.

Is there a way I can use PromQL to ignore the missing data point and calculate instead the increase based on the present data in the 10 min range?

increase() is not doing such extrapolation and returns an empty array.

Thanks

[Brian Candler]

That's exactly what increase() does.  It calculates the rate, based on the first and last data points in the time window and the time difference between them; and then multiplies this up to cover the whole range of the time window.

https://prometheus.io/docs/prometheus/latest/querying/functions/#increase

On Thursday, 20 August 2020 13:57:03 UTC+1, Vincehood wrote:

increase() is not doing such extrapolation and returns an empty array.

Show the actual query you are doing, and the actual data points in the time period. You need at least two data points of course, with the second higher than the first.