Topic: tcp

• Network throughput and retransmits on Linux: ss -ti, nstat, and iperf3

  ss -ti shows one connection's own retransmission and RTT view; nstat reports the same kind of counters host-wide from the kernel's SNMP and extended TCP statistics; iperf3 measures achievable throughput directly when retransmits are low but throughput still disappoints.

  methodology · en · reviewed · knowledge as of 2026-09-24

• TCP connections: the handshake, retransmission timers and keep-alives

  A TCP connection starts with a three-way handshake, recovers lost segments by a retransmission timer that doubles on each failure, and is only checked for liveness if keep-alives are switched on per socket. Linux defaults mean a hung peer takes minutes to notice and an idle connection two hours before the first probe.

  article · en · reviewed · knowledge as of 2026-09-15

Machine-readable: JSON