从AWS Kinesis Analytics传递滚动窗口数据的可靠性如何？

Question

When I analyze the contents of a Kinesis stream using a Kinesis Analytics SQL query grouping by time blocks, how certain can I be that all items in the stream are contained in the aggregates? Suppose I update the query during runtime, will the analytics application output aggregates v1 up to a point and then aggregates v2 for all items that were not yet reported on by v1? I something fails under the hood in the implementation, will a new node start reporting exactly from the point where the previous node ended? Or should you not rely on the completeness of these aggregations?

Answer 1

Answer posted on the AWS Forums, where I had cross posted:

Please see delivery semantics the service guarantees at https://docs.aws.amazon.com/kinesisanalytics/latest/dev/failover-checkpoint.html

Analytics service maintains checkpoints and if an update happens or any kind of failure happens, the application resumes from these checkpoints. Due to the design, it is possible the service reprocesses some of the same data and produces duplicates. Downstream applications should be able to handle that.