Web server architecture determines how many simultaneous HTTP/HTTPS connections an instance can sustain before thread exhaustion degrades Time to First Byte (TTFB).
1. Performance & Concurrency Benchmarks (10,000 Concurrent Keep-Alive Connections)
| Web Server Engine | Architecture Model | Requests Per Second (RPS) | Memory Footprint (10k Conns) | HTTP/3 QUIC Support |
|---|---|---|---|---|
| Nginx 1.26 | Asynchronous Event-Driven (epoll) | 48,500 RPS | 32 MB | Native (quiche / OpenSSL) |
| LiteSpeed Enterprise | Event-Driven + Native LSAPI | 49,200 RPS | 45 MB | Native built-in |
| Apache 2.4 (event MPM) | Hybrid Multi-Process / Thread | 31,200 RPS | 185 MB | mod_http2 / mod_quic |
| Apache 2.4 (prefork) | Process-per-connection (blocking) | 8,400 RPS | 950 MB (Thread Starvation) | Unsupported |