For a normal SQS, let's say having a visibility timeout of 30s. A message is consumed by one worker, and the worker doesn't delete the message from the SQS. Now, after 30s, the message becomes available again.

Exactly where in the SQS will this message be available? Will it be available at the start of the queue, where it will be consumed as soon as possible, or at the end of the queue?

CodePudding user response：

The answer is somewhere. In a standard SQS queue, there is no guarantee about the order of messages. From experience, it seems like they will appear somewhere at the front of the Queue, but as far as I know, that's not a documented behavior you should rely on.