tree b52f854bfab48bb5412a4b722e191debff1bc990
parent deb215257bf08c0ee1bbd2b9b8d7d73efe33358d
author JP Abgrall <jpa@google.com> 1391827210 -0800
committer Simon Wilson <simonwilson@google.com> 1416958085 -0800

tcp: add a sysctl to config the tcp_default_init_rwnd

The default initial rwnd is hardcoded to 10.

Now we allow it to be controlled via
  /proc/sys/net/ipv4/tcp_default_init_rwnd
which limits the values from 3 to 100

This is somewhat needed because ipv6 routes are
autoconfigured by the kernel.

See "An Argument for Increasing TCP's Initial Congestion Window"
in https://developers.google.com/speed/articles/tcp_initcwnd_paper.pdf

Change-Id: I386b2a9d62de0ebe05c1ebe1b4bd91b314af5c54
Signed-off-by: JP Abgrall <jpa@google.com>