From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oleksandr Natalenko <oleksandr@natalenko.name>
Subject: Re: TCP and BBR: reproducibly low cwnd and bandwidth
Date: Fri, 16 Feb 2018 20:54:47 +0100
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Cc: Neal Cardwell <ncardwell@google.com>,
        Eric Dumazet <eric.dumazet@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Netdev <netdev@vger.kernel.org>,
        Yuchung Cheng <ycheng@google.com>,
        Soheil Hassas Yeganeh <soheil@google.com>,
        Jerry Chu <hkchu@google.com>,
        Eric Dumazet <edumazet@google.com>,
        Dave Taht <dave.taht@gmail.com>
To: Holger =?ISO-8859-1?Q?Hoffst=E4tte?=
        <holger@applied-asynchrony.com>
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Hi.

On p=E1tek 16. =FAnora 2018 18:56:12 CET Holger Hoffst=E4tte wrote:
> There is simply no reason why you shouldn't get approx. line rate
> (~920+-ish) Mbit over wired 1GBit Ethernet; even my broken 10-year old
> Core2Duo laptop can do that. Can you boot with spectre_v2=3Doff and try "=
the
> simplest case" with the defaults cubic/pfifo_fast? spectre_v2 has terrible
> performance impact esp. on small/older processors.

Just have tried. No visible difference.

> When I last benchmarked full PREEMPT with 4.9.x it was similarly bad and
> also had a noticeable network throughput impact even on my i7.
>=20
> Also congratulations for being the only other person I know who ever tried
> YeAH. :-)

Well, according to the git log on tcp_yeah.c and Reported-by tag, I was not=
=20
the only one there ;).

Regards,
  Oleksandr