What is PgBouncer and what problem does it solve in PostgreSQL?

PgBouncer is a lightweight connection pooler for PostgreSQL.

The problem it solves:

PostgreSQL creates a separate process for each client connection, which, with a large number of connections, leads to high server load and reduced performance.

PgBouncer maintains a connection pool, reusing connections among clients, which reduces the overhead of creating and destroying connections.

Main advantages:

• Reduces connection setup time.
• Lowers server load.
• Manages the number of concurrent connections.

Thus, PgBouncer helps scale applications that actively work with PostgreSQL, improving responsiveness and stability.