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azuretimertriggersazure-functionsexecution

Timer triggered Azure Function executes irregularly

I have a timer triggered Azure Function whitch executes every morning at 04:30 AM

public static void Run([TimerTrigger("0 30 4 * * *")] TimerInfo myTimer)

Now I noticed that the invocation log shows me quite different execution times:

public static void Run([TimerTrigger("0 30 4 * * *")] TimerInfo myTimer)

This function worked like a charm. Since one week I notice the below issues:

How can this be that there are executions 2 minutes before the defined time? And why there are executions up to 8 minutes (!!) after the defined time?

Another strange behaviour is that in a different environment I see that the exact same Azure Function is triggered multiple times within the same minute:

enter image description here

Could this be an issue with the display in the invocation log or does somebody know more about this strange effect?

Any hint is highly appreciated!

Solution

  • How can this be that there are executions 2 minutes before the defined time?

    An error of about two minutes may be normal, which may be related to the design.

    And why there are executions up to 8 minutes (!!) after the defined time?

    Processing time depends on the code you write and the size of the data processed.

    Another strange behaviour is that in a different environment I see that the exact same Azure Function is triggered multiple times within the same minute

    Please check if runOnStartup is set to True. I think this is caused by multiple instances running at the same time. You can refer to this official documentation.

    enter image description here