Decoding HikariCP: Why p95 Metrics Deceive and How to Read Pool Signals Right

Misinterpreting HikariCP metrics can mask real performance problems by conflating rejected connections with successful queries, leading to flawed optimization decisions. This hands-on analysis reveals how p95 latency aggregates fast rejections with slower successful responses, creating misleading signals. Understanding true pool behavior is critical for Java developers to diagnose actual bottlenecks and avoid costly configuration errors.