PGConf.Russia 2025

Diagnostic Methods: Analyzing the Issue of Long CREATE DATABASE Execution

This talk covers two cases of long CREATE DATABASE execution in PostgreSQL 11, which, in a Corosync/Pacemaker cluster configuration, caused node failover due to a monitoring timeout from the clustering software. The first case is related to a large shared buffers size, while the second involves the use of the WITH OWNER option during database creation and a large pg_shdepend system table (a feature of using the jBPM software).

The visibility map in PostgreSQL is an important mechanism for optimizing database performance, accelerating read operations, data cleanup, and indexing. Despite some limitations, such as memory consumption and fragmentation, its use can significantly enhance performance in high-load systems. Effective utilization of the visibility map requires proper configuration and monitoring, which is especially crucial in systems with large data volumes and high transaction concurrency.

In this talk, I will challenge architectural stereotypes about the impossibility of communication with external systems directly from a DBMS. PostgreSQL offers vast communication capabilities; you just need to know which extensions to use.

And when extensions aren't enough, you can create your own. For the Luxms BI project, we needed communication with NATS, so we developed our own extension in Rust. I’ll share the GitHub link and my experience of developing PostgreSQL extensions in Rust during this talk.