I'm using Grafana with prometheus datasource and I'm unable to calculate a success ration from 2 sums of rates. For example I have
sum by (application) (rate(http_request_path_endpoint_responses{application="service1",request_path="/otp"}[5m])) / sum by (application) (rate(http_request_path_endpoint_responses{application="service1",request_path="/session"}[5m]))
it doesn't return anything
Each of them works just fine and it produces the expected values but I can't divide them in order to get the ratio. Any idea? Thanks