>>mpweih+(OP)
One important drawback of SQS is that it's eventually consistent, you can read the same message twice from different workers. Nevertheless we keep using it with additional checks when it's critical, it's still the cheapest solution by maintenance.
FIFO (First-In-First-Out) queues are designed to enhance messaging between applications when the order of operations and events is critical, or where duplicates can't be tolerated
>>akvadr+dI
And it comes with the trade off of 3000 (batches) messages per second (and I bet some reduced potential availability). Sure, it’s a lot of messages for most people but non-FIFO SQS is one of the truly limitless services offered by AWS. No limits to raise, no soft maximums AWS staff ask you not to exceed. Just limitless scaling.