ArgumentOutOfRangeException in eventhub triggered function

Question

Hi,

I have an event hub triggered function which with "many" cardinality and uses default batch size 300. Often times when the request rate is high I get this exception:

System.ArgumentOutOfRangeException: Index and count must refer to a location within the buffer. Parameter name: chars at System.Text.EncoderNLS.GetBytes(Char[] chars, Int32 charIndex, Int32 charCount, Byte[] bytes, Int32 byteIndex, Boolean flush) at System.IO.StreamWriter.Flush(Boolean flushStream, Boolean flushEncoder) at System.IO.StreamWriter.Flush() at Microsoft.Azure.WebJobs.Host.CompositeTraceWriter.Flush() at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.<ExecuteWithLoggingAsync>d__14.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task) at Microsoft.Azure.WebJobs.Host.Executors.FunctionExecutor.<TryExecuteAsync>d__12.MoveNext()

Is this a bug?

Answer 1

I agree, this looks like a race condition. Filed to track:

https://github.com/Azure/azure-webjobs-sdk-script/issues/1640