What is one read capacity unit equivalent to for eventually consistent reads in DynamoDB?

One read capacity unit for eventually consistent reads in DynamoDB is equivalent to one read per second for items up to 4 KB in size. Eventually consistent reads provide the most flexibility and cost-effectiveness when accessing data, allowing for high performance while minimizing costs associated with read throughput.

Eventual consistency means that when a read request is made, it may not reflect the latest write unless that write has propagated to all storage locations. However, the advantage is that you can consume half the read capacity when compared to strongly consistent reads. In the case of strongly consistent reads, one read capacity unit would be required for each read operation on an item up to 4 KB.

Therefore, considering that it takes one read capacity unit to perform one eventually consistent read for an item of this size, this directly aligns with the understanding that one read capacity unit allows you to retrieve one 4 KB item per second under eventual consistency. This fundamental concept is essential for determining how to plan your read capacity in applications making use of DynamoDB.