IntelligentTiering

Intelligent-Tiering is a storage class in Amazon S3 that automatically moves objects between two access tiers to optimize costs for data with unknown or changing access patterns. The two tiers are Frequent Access and Infrequent Access. Objects are kept in the tier that best matches their recent access activity, with automatic movement designed to reduce storage costs without user intervention.

How it works: When an object is stored in Intelligent-Tiering, S3 monitors access patterns and, if an object is not accessed for a period (typically 30 days), it is moved from the Frequent Access tier to the Infrequent Access tier. If the object is accessed again, it is automatically returned to the Frequent Access tier. There are no lifecycle rules required to manage these movements, and data remains accessible with the same API and performance characteristics as other S3 storage classes.

Pricing and duration: Storage costs are charged separately for each tier, with an additional small per-object monthly monitoring and automation fee to support the tiering operation. There is a 30-day minimum storage duration for data in the Infrequent Access tier, after which objects may be moved back to Frequent Access if access patterns change. Retrieval from Infrequent Access follows standard data transfer rules, but there are no separate retrieval fees within Intelligent-Tiering itself.

Use cases and considerations: Intelligent-Tiering is suited for data with unpredictable or changing access patterns, such as large data lakes, backups, and long-term storage with sporadic access. It is less advantageous for data with consistently high or predictable access or for workloads requiring immediate, predictable access without any monitoring charges.

Limitations: Availability and pricing can vary by region, and the automatic tiering adds a monitoring cost that should be weighed against potential savings.