I have an Azure Function timer trigger that kicks off a durable function orchestration. This goes on to check if a file is waiting to be processed - and if so, does a bunch of processing on it. The file could appear more or less at any point during the day.
- Timer trigger is set with this schedule: 0 30 7-23/2 * * Tue (every 2 hours between 7am and 11pm, at 30 minutes past the hour)
- Azure Functions V3, .NET
- Deployed to a Linux Consumption Plan
For 6 days of the week, the app does nothing so will scale down to zero instances. When it comes round to Tuesday, the schedule does not fire. If I go into the Azure Portal for the function, this is enough to nudge it and the schedule then fires and does the processing as expected.
I went with Consumption Plan as this service only has some real work to do once per week, and when it does, it needs to scale-out to churn through as quickly as possible, before then scaling back down to zero. SO I didn't want to use an App Service Plan/Dedicate Plan when most of the time it's dormant.
Is this expected behaviour with timer triggers on consumption plan?