Archive
Hands-on pipe vs tmpfile IPC lab: 5.32 vs 1.51 GB/s bulk (fsync 0.57); 64 B RTT p50 3.3 us vs 70 us vs 289 us. Localhost measured, no Docker.
Hands-on TCP_NODELAY vs Nagle: 1-byte reuse 124k vs 73k RPS; 32×16B writes favor Nagle (~1.7× fewer OutSegs). Delayed-ACK mean trap on localhost.
Hands-on RLIMIT_NOFILE lab: soft=64 → EMFILE after 58 held accepts; soft=512 takes 200/200. Soft raises without root; hard does not. Real numbers.
Hands-on SO_REUSEPORT lab: ss shows 4 listen queues; backlog=8 flood 72% vs 62% OK; ~41% fewer ListenOverflows. Real localhost numbers, no Docker.
Hands-on TCP backlog lab: backlog=1 + slow accept → 34/200 OK, ListenOverflows +357; backlog=128 stays 200/200. Real ss + netstat numbers.
Hands-on UDS vs TCP loopback echo: connect-per ~3× RPS (49k vs 16k); reuse ~1.3×. Real Python numbers, no Docker.