Developer Tests PgCache Proxy on 16-Million-Row Postgres DB, Finds Real Speed Gains

A developer built a synthetic 16-million-row e-commerce database to benchmark PgCache, a Postgres proxy that caches query results and invalidates them via the database's replication stream rather than using timers or manual cache-busting logic. The setup required only enabling logical replication on Postgres and adjusting a shared-memory setting, after which PgCache automatically created its own publication and replication slot. Unlike materialized views or Redis-based caching, PgCache sits transparently in front of Postgres using the wire protocol, meaning applications need only change the port they connect to. Benchmarks ran four aggregate queries 150 times each at concurrency 10, comparing a properly indexed Postgres instance directly against the same instance fronted by PgCache. The project, tested on PgCache version 0.6.2, is fully reproducible via a public GitHub repository using Docker Compose.