I have a lambda function that is triggered by an sqs queue . I set batch size to 1 because I want each message to map to one lambda instance to benefit from concurrency and finish processing faster. However,after some trials with 1000 messages available in sqs queue max concurrent execution only reachs 50 although I reserve 1000 concurrency for my function. Is there a reason behind this behavior
1 Answers
One reason could be that your functions finish quickly. Thus there is no reason to span 1000 concurrent functions. Lambda polls the sqs at fixed intervals, so you can just span 1000 concurrent invocations in an instance. Similarly, lambda does not scale to 1000 in an instant. Please read the following for more details:
Related