AWS cancels serverless Postgres service that scales to zero

I learned the expensive wya that Aurora Serverless v2 does not, in fact, scale down to 0 when I created three instances for a few days when I was testing out configuration changes. It ended up costing us $300.

Aurora Postgres is an interesting product where AWS made significant changes to Postgres storage architecture, however it has a fairly high fixed cost.

It seems in many cases RDS Postgres is cheaper and even when using Aurora, using fixed-size instance classes instead of "serverless" autoscaling classes (with ACUs) is a lot cheaper. Fixed Aurora on-demand instances are roughly 17% the cost of ACUs. Fixed instances are usually >= 30% cheaper on top of that if you reserve.

Aurora heavily favors performance and availability over cost.

Serverless V2 is also shit. The minimal one equivalent ACU to a regular instance has lots of latency spikes and much slower than a t3 instance.

We also tried serverless Redis. We have a tiny machine at %10 CPU utilization, but sustained queries. It costs 20x more. We were very afraid of the result we just ran it for an hour to get an idea.

Serverless, pay per use sounds only good if you have very few or unusual traffic.

We just run a monolithic but stateless Spring Boot Application and a dedicated RDS instance with reader in stand by. Only serverless dependency is SQS because it works nice enough. This simple infra has allowed us to iterate and pivot our startup very fast as needed. We still need more customers though.

Serverless is a paradigm where you pay for capacity, not for a specific number of instances. It's extending "cattle, not pets" beyond VMs to databases.

In theory it provides better incentives for both parties:

Customers don't have to pick instance size, etc. to try and accomodate their workload. They can buy throughput, etc. in fractions of an actual instance. They can look at their quota usage to determine whether to "scale up" or "scale down".

Service providers are incentivized to optimize their software. If you sell instances + a service on top, there's a perverse incentive not to make your code too fast or people will buy fewer instances. In serverless, providers are incentivized to reduce their costs and optimize the entire stack.

Scale to zero isn't necessarily a property of serverless - a service provider can agree to keep your data on ice for free, but that's a business decision.

I guess a good opportunity for someone to build a good alternative. Although it's hard to get it right because if you scale to 0 people will complain about latency and if you don't it's not really serverless.