Can multiple PostgreSQL tables share a single replication slot for CDC?
I'm working with PostgreSQL CDC and I'm concerned about the resource consumption on AWS RDS Aurora due to replication slots. Each replication slot consumes as much I/O as the replicas, and having multiple slots can quickly exhaust the available I/O, which is expensive to increase. I'm trying to minimize the number of replication slots being created. Is there a way for the CDC process to share a replication slot if multiple tables are coming from the same database?
Rick Otten
Asked on Sep 18, 2023
Currently, we only support sharing publications, not replication slots across different direct CDC table sources. We are actively working on supporting sharing replication slots to address the issues you raised. If sharing publications does not resolve your issue, you could consider using Debezium CDC, which would require setting up Debezium Connect and Kafka. However, setting up Debezium and Kafka is a significant infrastructure lift that you might want to avoid. We are prioritizing improving direct CDC support to enable replication slots sharing.