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	Morton's message of "Sat, 7 Nov 2015 15:06:20 +0200")
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Cc: cake@lists.bufferbloat.net
Subject: Re: [Cake] Long-RTT broken again
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Jonathan Morton <chromatix99@gmail.com> writes:

> Okay, that seems to be working somewhat better now.  I=E2=80=99m still not
> getting 100Mbps throughput in either direction, but now it seems to be
> because the receive windows won=E2=80=99t open far enough - there=E2=80=
=99s enough
> buffering to prevent any packet loss.

Yeah, Linux is window limited at these BDPs with the default settings.
Try these sysctls on both sides:

net.core.rmem_max=3D16777216
net.core.wmem_max=3D16777216
net.ipv4.tcp_rmem =3D 4096 87380 104857600
net.ipv4.tcp_wmem =3D 4096 16384 104857600

-Toke