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Comment by larsmak | Hacker News Reader

I don't know, S3 and DynamoDB are both eventual consistent. And keeping in mind the CAP-theorem it makes sense. And I for one love SimpleDB - it's just that, simple. And great for prototyping (really cheap) and small production-loads. Often you just need a place to stick your data, scalability can be achieved to adding a caching layer.

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You can choose eventual or fully consistent in DynamoDB. Given that full consistency comes at a higher cost (read from a quorum of replicas) we expose that cost to you.

BTW nobody wants eventual consistency, it is a fact of live among many trade-offs. I would rather not expose it but it comes with other advantages ...

They have actually been making S3 _more_ consistent over time: in the newer regions you get e.g. read-your-writes for object creation. DynamoDB also supports consistency, though still defaults to eventual consistency if you prefer.

In my mind, there's definitely a trend towards consistency here. I'd love to see an AWS blog post about the reasons behind this!

We should be glad. Eventual consistency is hard to reason about, particularly when its tradeoffs have to do with other people's systems...

US Standard now provides read-after-write consistency when accessed through the Northern Virginia endpoint [1].

[1] http://aws.amazon.com/s3/faqs/#What_data_consistency_model_d...

i think you can force consistency on DynamoDB for a price.

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