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I know how consistency works when you create/update/delete a file on S3. What about S3 bucket listing operation? Is it strongly consistent or eventually consistent?

Alex B
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2 Answers2

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The List Objects operation appears to be eventually-consistent, even for new objects. According to a support forum post from an AWS employee ChrisP@AWS:

Read-after-write consistency is only valid for GETS of new objects - LISTS might not contain the new objects until the change is fully propagated.

— https://forums.aws.amazon.com/thread.jspa?messageID=687028&#687028

Michael - sqlbot
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The preceding answer of @Michael had been accurate before latest announcement from AWS.

AWS has recently announced that both read after write operation and list operation is now strongly consistent.

Snippet from AWS:"After a successful write of a new object, or an overwrite or delete of an existing object, any subsequent read request immediately receives the latest version of the object. S3 also provides strong consistency for list operations, so after a write, you can immediately perform a listing of the objects in a bucket with any changes reflected."

Reference - https://aws.amazon.com/s3/consistency/

Tejaskumar
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