Amazon S3 Strong Consistency
Overview
Amazon S3 delivers strong read-after-write consistency automatically for all applications, without changes to performance or availability, without sacrificing regional isolation for applications, and at no additional cost. With strong consistency, S3 simplifies the migration of on-premises analytics workloads by removing the need to make changes to applications, and reduces costs by removing the need for extra infrastructure to provide strong consistency.
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.
What is strong consistency?
Benefits
How strong consistency for Amazon S3 works?
Dropbox
"Strong read-after-write consistency is a huge win for us because it helps drive down the time to complete our data processing pipelines by removing the software overhead needed to deliver consistency, and it also reduces our cost to operate the data lake by simplifying the data access architecture."
Ashish Gandhi, Technical Lead Data Infrastructure - Dropbox

Salesforce
"We’ve been using Amazon S3 and the new strong consistency model to enable users to access the petabytes of log data in production systems around the world. Strong consistency is important for our Presto-Hive based data processing workflows. Before the change in consistency model, we were planning for edge cases where eventually consistent directory listings could produce incorrect query results. Now, with S3 strong consistency, we are confident that our data platform will always provide accurate and consistent query results."
Anil Ranka, Senior Director - Infrastructure Engineering - Salesforce | Vincent Poon, Principal Engineer - Salesforce
