Design Cost-Optimized Architectures

Standard bills read and write I/O separately, while I/O-Optimized includes read and write I/O in its configuration price; both still require a workload-specific total-cost comparison. — DocumentDB Standard has a separate I/O request meter. I/O-Optimized includes those read and write operations in its storage configuration pricing, which can benefit I/O-intensive clusters. Compute, storage, backup, and transfer usage still need to be modeled.

Both configurations charge the same separate per-I/O rate, so storage configuration never affects an I/O-intensive workload's bill. — The reason to evaluate I/O-Optimized is precisely that it removes the separate read/write I/O meter used by Standard.

I/O-Optimized removes instance-hour, storage, backup, and data-transfer charges in addition to I/O charges. — The configuration changes I/O pricing, not the existence of provisioned instances, stored data, excess backups, or applicable transfer charges.

Standard includes all I/O, while I/O-Optimized charges every read and write operation separately. — Standard is the configuration with separate I/O request charges; I/O-Optimized includes read and write I/O in its pricing model.