Server Performance Tuning — Production Linux Performance Tuning Checklist Before tuning, always establish a baseline: --- Kernel / Network Tuning via sysctl : Apply immediately: --- File Descriptor (ulimit) Configuration System-wide: Requires PAM to be active (enabled by default on Ubuntu). Verify: Per-Service Systemd Override : : --- Nginx Performance Configuration (worker and global section): Test and reload: --- PgBouncer: PostgreSQL Connection Pooling Postgres creates a new OS process per connection ( 5–10 MB RAM). At 500 connections that is 2.5–5 GB overhead before a single query runs. P…