title: Increase Initial TCP Congestion Window to 10
name: tcp_init_cwnd.stp
version: 1.0
author: anonymous
keywords: network tcp socket guru
subsystem: network
scope: system-wide
status: proposed
exit: user-controlled
output: trace on-exit
description: Run the tcp_init_cwnd.stp script in the background to override a kernel's default tcp cwnd value to 10, which has been found to improve latency for web server type workloads.  The script prints a count of cwnd value changes when it is stopped.
test_check: stap -g -p4 tcp_init_cwnd.stp
test_installcheck: stap -g tcp_init_cwnd.stp -c "sleep 0.2"
