[jaggederest]

I've had better results with managing my own clusters on metal instances. You get much better performance with e.g. NVMe drives in a 0+1 raid (~million iops in a pure raid 0 with 7 drives) and I am comfortable running my own instances and clusters. I don't care for the way RDS limits your options on extensions and configuration, and I haven't had a good time with the high availability failovers internally, I'd rather run my own 3 instances in a cluster, 3 clusters in different AZs.

Blatant plug time:

I'm actually working for a company right now ( https://pgdog.dev/ ) that is working on proper sharding and failovers from a connection pooler standpoint. We handle failovers like this by pausing write traffic for up to 60 seconds by default at the connection pooler and swapping which backend instance is getting traffic.