Postgres Postmaster does not scale

The postmaster process in PostgreSQL runs a single-threaded main loop that handles connection spawning, worker reaping, and parallel query workers. Under extreme load with high connection rates (1400+ connections/sec) and background worker churn, this single-threaded bottleneck can saturate a CPU core, causing 10-15 second delays in connection establishment. The issue was traced through profiling to expensive fork operations and compounded by parallel query workers. Solutions include enabling huge pages for 20% throughput improvement, adding connection jitter to reduce peak rates, and eliminating parallel query bursts. This architectural constraint explains why connection pooling tools are essential for scaled PostgreSQL deployments.