Our engineers discovered a bug in PostgreSQL that was promptly reported upstream (https://www.postgresql.org/message-id/1958255.PYKUYFuaPT%40aivenlaptop). We are still focused on finding the root cause and creating a fix.
We did not find any evidence that the bug has led to corruption on any Aiven for PostgreSQL 16 service. However, this issue will show up as a corruption of the Free Space Map (FSM), forcing the database to return errors on write operations.
This scenario appears more frequently on small instances and is only affecting a small number of Aiven for PostgreSQL 16 services.
Creation of new Aiven for PostgreSQL 16 services is available again.
Upgrading existing Aiven for PostgreSQL services to version 16 will remain unavailable while our engineers thoroughly examine the issue to ensure it does not negatively interact with the upgrade process.
We have identified repair actions where this issue occurs.
We are focusing on finding and fixing the root cause of the issue.