问题
I have a AWS Lambda with limited concurrency set that is consuming messages from a AWS SQS of type FIFO, and I just learned that the "messages in flight"-property of the queue does not reflect the number of concurrent lambdas processing the messages.
However, do I need to worry that the Default Visibility Timeout of the queue will time out before a lambda or in the middle of a lambda just having received a message? Or rather is the Default Visibility Timeout counted from when the message was turned into "in-flight", or is it counted from when the lambda start processing the message?
Judging from the Amazon SQS visibility timeout documentation it almost sound like the former, but I feel that it still a bit vague and it would be helpful if someone knew for sure.
来源：https://stackoverflow.com/questions/61116499/timeout-behaviour-when-aws-lambda-with-limited-concurrency-is-consuming-from-an