What type of consistency model do S3 buckets in all regions (besides the US standard) adhere to for PUTS of new objects?

Amazon S3 buckets, except for the US Standard region, adhere to a read-after-write consistency model for PUTS of new objects. This means that once a new object is created in S3, any subsequent read request to access that object will return the latest version. This consistency is crucial in maintaining accurate data access where immediate feedback is often necessary.

With read-after-write consistency, applications can reliably retrieve newly written data immediately after the write operation without experiencing stale data issues. This is particularly important for applications that depend on immediate validation of data operations, such as logging systems or where user-generated content is involved.

In contrast, other options like eventual consistency describe a model where the updates might not be immediately visible, leading to discrepancies upon reads immediately after a write operation. Immediate consistency implies that changes are instantly visible, which while related, does not accurately reflect the guarantees provided by S3's design, particularly in other regions outside the US Standard which ensures newer data is promptly available for reads. Thus, it's essential to recognize the specific consistency model S3 employs for new object writes to understand its operational mechanics effectively.