What is the unit for health check metric

Question

Hi I need some help understanding how to read the health check metric.

I have this Azure function, at 10:27 the health check status with aggregation = count is 5. Aggregation = Sum is 500. And Max, Min, Avg is 100. How does 5 requests sum up to 500? 500 of what?
My guess is Azure probably ping this service 5 times at this time period. And then a successful ping result in value = 100? I found no evident in the documentation.
Some document I checked: https://learn.microsoft.com/en-us/azure/app-service/monitor-instances-health-check?tabs=dotnet
https://learn.microsoft.com/en-us/azure/azure-monitor/essentials/metrics-aggregation-explained
https://learn.microsoft.com/en-us/answers/questions/756241/what-is-the-healthcheckstatus-metric-in-azure-app

What is the unit for the y axis?

Answer 1

Hi, The unit is percentage. In this case you should use Avg aggregation as Count and Sum will give you the number of times the health check was performed. Keep in mind that the metric has dimension for instance so when you do not split by instance whatever aggregation you choose will show the values for all instances. So avg will show the average percentage of availability for all instances, count will show the number of health checks performed for all instances. You also time granularity to configure for the chart and the lowest you can configure is every 5 minutes.

Please "Accept the answer" if the information helped you. This will help us and others in the community as well.