Choosing right RDS Instance type for SQL Server

Hi,

To right-size while optimizing your costs, I would suggest 2 complementary options:

1. separate each of your distinct databases in its own RDS instance. This way you will be able to optimize the full setup (sizing, storage, backup, HA) individually to best match the needs without having to decide based on the most demanding of your 4 dbs.
2. leverage auto-scaling for both storage: https://aws.amazon.com/about-aws/whats-new/2019/06/rds-storage-auto-scaling/ to avoid under- or overprovisionning until you know well capacity that you need if you eventually want to shift to a static configuration. It happens without downtime. For compute scaling: you have to choose between 2 options: horizontal or vertical scaling depending on your use case. This blog will help you to choose: https://aws.amazon.com/blogs/database/scaling-your-amazon-rds-instance-vertically-and-horizontally/

Best,

Didier

Hello,

You can start by matching your existing database servers' vCPU and memory configuration.Then if you need you can upsize your instance size as per your need. It is also good to overprovision by 10-20% initially to allow for future growth

Below are a few links you can refer to that will help you in choosing the right size for your RDS -

https://docs.aws.amazon.com/whitepapers/latest/cost-optimization-right-sizing/tips-for-right-sizing-your-workloads.html

https://aws.amazon.com/blogs/database/capture-and-tune-resource-utilization-metrics-for-amazon-rds-for-sql-server/

Thanks