Blob trigger function firing consistenly with delay more then 1 hour

Question

I have a blob trigger function that fires when a new file uploaded to the blob storage. It's firing with a huge delay of at least 1 hour. How I can determine this problem?

Answer 1

Hello @Pavel Haletski , Thank you for sharing the information offline. I am posting the observation here:

• High CPU & memory: Your App Service Plan is nearing saturation. For production applications, it is recommended that an App Service Plan does not exceed a certain number of sites. The number may be lower depending on how resource intensive the hosted applications are, however as a general guidance, you may refer to the table below.

Worker Size ------- Max sites
Small -------------- 8 ( Currently its 9)
Medium ----------- 16
Large -------------- 32

We recommend scaling up to a higher App Service Plan ( Premium) or adding more instances to the current one( from S1 to S2) to have the load distributed among more instances and not have High CPU Usage.
Also make sure if you have written any code, then the errors and exceptions are handled properly.

• Function Host Name Collision: This limit might affect Timer trigger, Blob trigger functions if the listed Function App(s) connecting to same storage account, As a workaround if you are running into this issue, you can set an explicit HostID in app settings. https://learn.microsoft.com/en-us/azure/azure-functions/functions-bindings-timer?tabs=csharp#function-apps-sharing-storage

The host ID value should be unique for all apps/slots you're running. A host ID must be between 1 and 32 characters, contain only lowercase letters, numbers, and dashes, not start or end with a dash, and not contain consecutive dashes. https://github.com/Azure/azure-functions-host/issues/2015

If it is not possible to add AzureFunctionsWebHost__hostid (V2+) or id (V1), the only other option is to reduce the length of the site name to less than 32 characters. As there exists no means to rename a function, the customer must therefore, delete and recreate it with a new compliant name.

Please let me know if this helps. If it doesn’t, I would recommend you open a support ticket with Microsoft Support if you have a subscription which allows you to do so. Otherwise , I will enable you for one-time free support. ( Please confirm the subscription Id offline)