Krishnamurthy says he is more than happy with the performance and stability of the new solution. "Things have been running very smoothly on Aurora since the migration," he says. "There have been zero database outages, and we no longer have to worry about the execution plan flips we used to experience on Oracle."

Now that AWS is responsible for most management tasks—such as patching, maintenance, backups, and upgrades—engineers can turn their attention to more valuable work. "We used to need three database engineers to keep Oracle up to date and take care of performance improvement tasks like repartitioning and index tuning," says Gage. "Because Aurora reduced our administrative overhead by about 70 percent, we don't need those resources just to keep our heads above water and can shift them to more valuable tasks."

The migration also resulted in considerable cost savings. "Another big benefit of the migration is the lower cost of database hosting on AWS," says Krishnamurthy. "On Amazon Aurora, we see performance levels similar to what we saw on Oracle at less than half the cost."

And, using AWS, the team no longer has any concerns about scale. "After the migration, we load-tested the new and the old systems up to 900 transactions per second per shard,” says Gage. "Aurora had no problem handling the load, with minimal CPU usage, while Oracle browned out. We also had no problems in any of our regions on

Gage says the project was much less challenging than some might have expected. "In the end, migrating from Oracle onto AWS turned out to be pretty simple. We hit obstacles, but we were able to overcome them either on our own or with the help of the AWS DMS team, who really provided exemplary support of their product. Amazon Aurora was the easiest part of the migration. It never gave us the slightest problem."