[maxmorlocke]

For a typical db.t3.xlarge instance, you're talking about 29c/hour vs 27.2c per hour. That's $157.68 as the total difference for one year's runtime, when the whole instance cost for postgres would be $2540.4 for the year, or about 6%. The larger the machine, the closer to parity. Given the absolutely small difference, I hope this isn't the dividing line in any commercial project.

[chunk_waffle]

Again, I don't still know if this is the case, but you could use smaller instances with MySQL aurora than with Postgres, given the way our application worked it would have made a big difference for us if we had used mysql.

RDS/Aurora was our most expensive resource so we were looking at ways to cut that cost down and mysql was one option (though the way the app worked and the extensions that it relied on made it not a possibility.)