Amazon DocumentDB (with MongoDB compatibility) offers two storage configurations: and IO-Optimized . The IO-Optimized configuration is designed for applications with high input/output (I/O) demands. It provides predictable performance by decoupling I/O charges from storage usage, making it cost-effective for I/O-intensive workloads. This report explains the architecture, benefits, use cases, and cost implications of the IO-Optimized setting.
To decide if IO-Optimized fits:
: Can be enabled via the AWS Management Console , AWS CLI, or SDKs. It is also supported in Terraform AWS Provider v5.29.0 and later. AWS announces Amazon DocumentDB I/O-Optimized documentdb io optimized
A typical two-instance db.r5.large cluster with 1,000 million I/Os per month can see a when moved to I/O-Optimized, as the included I/O costs offset the higher instance and storage fees. For even more control, teams often use the AWS Pricing Calculator to model their specific traffic before making the switch. AWS announces Amazon DocumentDB I/O-Optimized This report explains the architecture, benefits, use cases,
: You can switch existing clusters to I/O-Optimized storage once every 30 days . Switching back to Standard can be done at any time. usage-dependent | Fixed
| Feature | Standard | IO-Optimized | |--------|----------|---------------| | I/O charges | Yes (per million requests) | No (included) | | Storage price | Lower per GB-month | Higher per GB-month (~2x Standard) | | Predictability | Variable, usage-dependent | Fixed, based on data volume | | Best for | Low to moderate I/O workloads | High I/O, latency-sensitive workloads |